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Chlorodifluoromethane. TOXNET profile from Hazardous Substances Data Base.
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CHLORODIFLUOROMETHANE
CASRN: 75-45-6
For other data, click on the Table of Contents
Human Health Effects:
Evidence for Carcinogenicity:
Evaluation: There is inadequate evidence in humans for the carcinogenicity
of chlorodifluoromethane. There is limited evidence in experimental animals
for the carcinogenicity of chlorodifluoromethane. Overall evaluation: Chlorodifluoromethane
is not classifiable as to its carcinogenicity in humans (Group 3).
Human Toxicity Excerpts:
IN EPIDEMIOLOGICAL STUDY OF HOSPITAL PERSONNEL, A 3.5-FOLD EXCESS OF PALPITATION
WAS NOTED IN THOSE EXPOSED TO MONOCHLORODIFLUOROMETHANE.
EARLY ... HUMAN EXPERIENCE INDICATED THAT HIGH VAPOR CONCN (EG, 20%) MAY CAUSE
CONFUSION, PULMONARY IRRITATION, TREMORS & RARELY COMA, BUT THAT THESE EFFECTS
WERE GENERALLY TRANSIENT & WITHOUT LATE SEQUELAE. ... CAUSE OF DEATH /FROM
ABUSE OF FLUOROCARBONS/ IS IN CONSIDERABLE DOUBT ... FREEZING OF AIRWAY SOFT
TISSUES CAN PROBABLY BE ELIMINATED AS A CAUSE OF DEATH EXCEPT IN CASES WHERE
THE PRODUCT WAS SPRAYED DIRECTLY INTO THE MOUTH FROM ITS CONTAINER OR FROM A
BALLOON CONTAINING SOME LIQUID. LARYNGEAL SPASM OR EDEMA, OXYGEN DISPLACEMENT,
OR SENSITIZATION OF MYOCARDIUM TO ENDOGENOUS CATECHOLAMINES WITH SUBSEQUENT
VENTRICULAR FIBRILLATION APPEAR TO BE REASONABLE POSSIBILITIES. /FLUOROCARBON
REFRIGERANTS & PROPELLANTS/
EXCESSIVE SKIN CONTACT WITH LIQUID FLUOROCARBONS SHOULD BE MINIMIZED TO PREVENT
DEFATTING OF SKIN ... /FLUOROCARBONS/
Chlorodifluoromethane did not induce unscheduled DNA synthesis in human heteroploid
EUE cells treated with a 20 mM soln generated at 500 ml/min (1:1 air) in presence
or absence of S10.
An epidemiological study was made of 539 refrigeration workers exposed to
a combination of chlorofluorocarbons, including chlorodifluoromethane, for at
least 6 mo between 1950 to 1980 and followed up until 1980. There were 6 deaths
due to cancer versus 5.7 expected, with 2 deaths from lung cancer versus 1.0
expected. (The Working Group noted that the study was small and there were few
deaths from cancer.)
A GAS OF LOW TOXICITY, BUT VERY HIGH CONCENTRATIONS ARE NOT ENTIRELY INERT.
POSSIBLE LUNG INJURY.
A SPECIAL CLASS OF CHEMICALS SUBJECT TO ABUSE BY INHALATION ARE THE FLUOROHYDROCARBONS,
SUCH AS ... CHLORODIFLUOROMETHANE ... THE "SNIFFING" OF SUCH AEROSOL SPRAYS
IS HAZARDOUS PRACTICE. ... 110 "SUDDEN SNIFFING DEATHS" /HAVE BEEN IDENTIFIED/
... IN EACH CASE THE VICTIM SPRAYED THE AEROSOL INTO A PLASTIC BAG, INHALED
THE CONTENTS, BECAME EXCITED, RAN 90 M OR SO, COLLAPSED, & DIED. NECROPSY
FINDINGS WERE LARGELY NEGATIVE ... ALTHOUGH AMOUNT OF PROPELLANT ABSORBED INTO
BLOOD FROM USE OF HAIRSPRAY, COSMETIC, HOUSEHOLD, & MEDICATED AEROSOLS MUST
VARY WITH CIRCUMSTANCES, PHYSICIAN IS ADVISED TO COUNSEL ... PATIENT ON POTENTIAL
DANGERS, PARTICULARLY FROM THEIR USE IN POORLY VENTILATED CONFINED AREAS. /FLUOROHYDROCARBONS/
Liquid may cause frostbite.
... LOWER IN TOXICITY THAN CORRESPONDING CHLORINATED OR BROMINATED HYDROCARBONS.
... ASSOC WITH GREATER STABILITY OF C-F BOND; & PERHAPS ALSO WITH LOWER
LIPOID SOLUBILITY ... TOXIC EFFECTS FROM REPEATED EXPOSURE, SUCH AS LIVER OR
KIDNEY DAMAGE, HAVE NOT BEEN PRODUCED BY FLUOROMETHANES ... /FLUOROCARBONS/
Two groups of three male volunteers were exposed by inhalation to chlorodifluoromethane
at either 327 or 1833 mg/cu m for 4 hr. The average maximal blood concentrations
were 0.25 and 1.36 ug/ml, respectively, and were achieved within 1 hr of the
beginning of exposure. The average blood/air partition coefficients for chlorodifluoromethane
towards the end of the exposure period were 0.82 and 0.76, respectively, and
the fat/air partition coefficients were 7.7 and 8.1. Thus, the fat/blood partition
coefficient was estimated to be approximately 10. Three phases for the elimination
of chlorodifluoromethane in breath were identified, with estimated half-lives
of 0.005, 0.2 and 2.6 hr. An average of 2.1% of the inhaled chlorodifluoromethane
was recovered from the exhaled air over 26 hr and minimal amounts were found
in urine. Minimal changes in the fluoride
concentration in urine were observed, which is consistent with a low degree
of metabolism.
Two simultaneous accidental, lethal exposures to chlorodifluoromethane alone
were associated with concentrations (in ul/ml) of the chemical in body fluid
samples taken 16 hr after death of: blood, 37.1 and 26.0; urine, 1.7 and 0.9;
vitreous humor, 1.0 and 0.7.
The effects of occupational exposure to chlorodifluoromethane (FC 22) &
dichlorodifluoromethane (FC 12) on cardiac rhythm were examined. The subjects
were 6 men who repaired refrigerators (age 31-56, mean 46 yr) & a control
group of six plumbers (age 29-54, mean 45 yr). Ambulatory electrocardiograms
(ECG) were recorded for 24 hr on the day of exposure & on a control day.
The ECG tapes were automatically analysed with a Reynolds pathfinder 3 apparatus
& all aberrant complexes recorded by the machine were checked. One person
read all the tapes without knowing whether or not they were recorded during
exposure. The number of ventricular ectopic beats were compared between the
day of exposure & the control day & with the tape of the control. In
addn, the number of ventricular ectopic beats during exposure was compared with
the number occurring during the rest of the day. The concns of fluorocarbons
were measured in 4 instances. High peak concns of fluorocarbons (1300-10,000
cm3/m3) were measured during refrigerator repair work. No clear connection between
fluorocarbons & cardiac arrhythmia was found, although one subject had several
ventricular ectopic beats which may have been connected with exposure.
The prevalence of cardiac arrhythmia in refrigerator repairmen exposed to
fluorocarbons (FCs) was assessed in a field study of 89 repairmen. The exposure
concns of FCs in the breathing zone were measured by experienced industrial
hygienists using a direct recording infrared spectrometer. The recording of
heart activity was carried out at the same time as the measurement of FCs. Most
cooling systems contained FC-12 (75718) or FC-22 (75456). The highest FC level
recorded in 1 min was 14,000 ppm & the highest time weighted exposure during
8 hr was 280ppm. Two types of arrhythmia were detected, ectopic beats &
sudden bradycardias. In a within subject comparison, no significant differences
between arrhythmia frequencies during exposed & unexposed periods &
no consistent dose effect relations were observed. The frequencies of arrhythmia
when unexposed were somewhat higher than previously reported. Misclassification
of exposure & the possible confounding effect of physical workload &
psychological strain may have obscured any causal relation. The authors conclude
that the results do not support the notion that FCs induce cardiac arrhythmia
in occupationally exposed refrigerator repairmen.
Reports on fatalities of chlorofluorocarbons usually involve chlorotrifluoroethane,
trichlorofluoromethane, dichlorodifluoromethane or chlorodifluoromethane, where
analysis was done using packed column gas chromatography. In this case a death
was caused by an azeotropic mixture of chlorodifluoromethane & chloropentafluoroethane,
a combination that has not previously been reported in the forensic literature.
This report details the analysis using mass selective detection employing capillary
gas chromatography columns currently used in many toxicology laboratories. Postmortem
toxicology revealed blood concns of chlorodifluoromethane & chloropentafluoroethane
of 71 mg/L & 0.30 mg/L, respectively. Brain,
liver, & lung concns of chlorodifluoromethane were (mg/kg) 2.8, 4.4, and
1.6, respectively. Brain, liver, & lung
concns of chloropentafluoroethane were (mg/kg) 0.80, 0.80, & 0.11, respectively.
The victim's blood contained 5.5 mg/L caffeine. Lidocaine, used in resuscitation
attempts, was also present in the victim's blood. No other alkali-extractable
drugs or volatile alcohols were detected in the victim's blood. The cause of
death was acute respiratory arrest due to chlorofluorocarbon inhalation.
Two cases of lethal poisoning due to chlorodifluoromethane (Freon 22) inhalation
are described. The fluorocarbon was determined in biological tissues by headspace
gas chromatography/mass spectrometry. Ions monitored were m/z 67, 86 & 51,
the latter being used for quantification. Blood concentrations were 26.0 &
37.1 mul/ml. In both cases, the drug was also identified in urine, vitreous
humor and bile, but in much lower concentrations.
Skin, Eye and Respiratory Irritations:
Vapor not irritating to eyes, nose, or throat.
Populations at Special Risk:
IT IS POSSIBLE THAT PATIENT WITH CARDIAC OR RESP DISORDERS MAY PROVE ESP SUSCEPTIBLE.
/FLUOROCARBONS/
Probable Routes of Human Exposure:
THERE ARE ISOLATED REPORTS OF POISONING FROM EXPOSURE TO FLUOROCARBON PROPELLANTS
& SOME STUDIES SHOWING A HIGHER INCIDENCE OF CORONARY HEART DISEASE AMONG
HOSPITAL PERSONNEL & REFRIGERANT MECHANICS EXPOSED TO FLUOROCARBONS. ADDITIONAL
INVESTIGATION IS REQUIRED TO ESTABLISH CAUSAL RELATIONSHIP BETWEEN FLUOROCARBONS
& CARDIOVASCULAR & BRONCHOPULMONARY DISEASES AMONG EXPOSED WORKERS.
THE HIGH INCIDENCE OF CANCER AMONG HOSPITAL PERSONNEL REPEATEDLY EXPOSED TO
FLUORINE-CONTAINING GENERAL ANESTHETICS RAISES A FUNDAMENTAL NEED TO EXAMINE
OTHER FLUOROCARBON-EXPOSED WORKERS FOR SIMILAR EFFECTS. /FLUOROCARBONS/
...Exposure in chemical plant operations and production is generally low but
highly variable, and may be high in areas without adequate ventilation. Cylinder
packers and shippers have occasional high exposure. Exposure during tank farm
operations, and tank and drum filling, may exceed the threshold limit value.
Tank truck and tank car fillers have potentially high exposure, which may be
intermittent with the occurrence of accidents. Maintenance operators, laboratory
analysts, and supervisory personnel have low exposure. The highest exposure
in the plant occurs with venting of gases from returnable cylinders. The formation
of high-temperature thermal decomposition products may occur during storage.
NIOSH (NOES Survey 1981-1983) has statistically estimated that 149,149 workers,
including 8,054 women, are potentially exposed to chlorodifluoromethane in the
USA(1). Occupational exposure to chlorodifluoromethane may occur through inhalation
and dermal contact with this compound at workplaces where chlorodifluoromethane
is produced or used(SRC). Monitoring data indicate that the general population
may be exposed to chlorodifluoromethane via inhalation of ambient air(2,3) from
and leaky refrigeration units containing chlorodifluoromethane(4).
In one study, workers in a fluorocarbon shipping and packaging plant were
exposed to 4.7-13.5 ppm of chlorodifluoromethane(1).
Body Burden:
A pilot study of volatile organic chemicals in mother's milk found that two
of eight samples of milk obtained from women in 4 urban areas in the United
States contained chlorodifluoromethane; the levels were not quantified(1).
Two simultaneous accidental, lethal exposures to chlorodifluoromethane alone
were associated with concentrations (in ul/ml) of the chemical in body fluid
samples taken 16 hr after death of: blood, 37.1 and 26.0; urine, 1.7 and 0.9;
vitreous humor, 1.0 and 0.7.
Emergency Medical Treatment:
Emergency Medical Treatment:
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SHOULD BE CONSULTED FOR ASSISTANCE IN THE DIAGNOSIS OR TREATMENT OF SPECIFIC
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Reserved. Any duplication, replication or redistribution of all or part
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is strictly prohibited.
The following Overview, *** FLUORINATED HYDROCARBONS ***, is relevant for this HSDB record chemical. |
| Life Support: |
o This overview assumes that basic life support measures
have been instituted.
|
| Clinical Effects: |
SUMMARY OF EXPOSURE
0.2.1.1 ACUTE EXPOSURE
o LOW CONCENTRATION - Inhalations such as those caused by
leaking air conditioners or refrigerators usually
result in transient eye, nose, and throat irritation.
Palpitations, light headedness, and headaches are also
seen.
o HIGH CONCENTRATION - Inhalation associated with
deliberate abuse, or spills or industrial use occurring
in poorly ventilated areas has been associated with
ventricular arrhythmias, pulmonary edema and sudden
death.
HEENT
0.2.4.1 ACUTE EXPOSURE
o EYES - Eye irritation occurs with ambient exposure.
Frostbite of the lids may be severe. Ocular
instillation results in corneal burns in rabbits.
o NOSE - Nasal irritation occurs with ambient exposure.
o THROAT - Irritation occurs. Frostbite of the lips,
tongue, buccal mucosa and hard palate developed in a
man after deliberate inhalation.
CARDIOVASCULAR
0.2.5.1 ACUTE EXPOSURE
o Inhalation of high concentrations is associated with
the development of refractory ventricular arrhythmias
and sudden death, believed to be secondary, primarily,
to myocardial sensitization to endogenous
catecholamines. Some individuals may be susceptible to
arrhythmogenic effects at lower concentrations.
RESPIRATORY
0.2.6.1 ACUTE EXPOSURE
o Pulmonary irritation, bronchial constriction, cough,
dyspnea, and chest tightness may develop after
inhalation. Chronic pulmonary hyperreactivity may
occur. Adult respiratory distress syndrome has been
reported following acute inhalational exposures.
Pulmonary edema is an autopsy finding in fatal cases.
NEUROLOGIC
0.2.7.1 ACUTE EXPOSURE
o Headache, dizziness, and disorientation are common.
Cerebral edema may be found on autopsy. A syndrome of
impaired psychomotor speed, impaired memory and
learning, and emotional lability has been described in
workers with chronic occupational exposure to
fluorinated hydrocarbons.
GASTROINTESTINAL
0.2.8.1 ACUTE EXPOSURE
o Nausea may develop. Ingestion of a small amount of
trichlorofluoromethane resulted in necrosis and
perforation of the stomach in one patient.
HEPATIC
0.2.9.1 ACUTE EXPOSURE
o Jaundice and mild elevations in transaminases may
develop after inhalational exposure or ingestion.
Hepatocellular coagulative necrosis has been observed
on liver biopsy.
DERMATOLOGIC
0.2.14.1 ACUTE EXPOSURE
o Dermal contact may result in defatting, irritation or
contact dermatitis. Severe frostbite has been reported
as an effect of freon exposure. Injection causes
transient pain, erythema and edema.
MUSCULOSKELETAL
0.2.15.1 ACUTE EXPOSURE
o Rhabdomyolysis has been reported in a worker
susceptible to malignant hyperthermia after exposure to
fluorinated hydrocarbons and also following intentional
freon inhalation. Compartment syndrome is a rare
complication of severe exposure.
REPRODUCTIVE HAZARDS
o Dichlorodifluoromethane was not teratogenic in rats and
rabbits.
o The reproductive effects of 1,1,1,2-tetrafluoroethane
were studied in rats. No adverse effects on
reproductive performance was noted or on the
development, maturation or reproductive performance of
up to two successive generations.
GENOTOXICITY
o The hydrochlorofluorocarbons, HCFC-225ca and HCFC-225cb,
were not mutagenic in the Ames reverse mutation assay,
or clastogenic in the chromosomal aberration assay with
Chinese hamster lung cells. Neither induced unscheduled
DNA synthesis in liver cells. Both of these agents were
clastogenic in the chromosomal aberration assay with
human lymphocytes.
|
| Laboratory: |
o Fluorinated hydrocarbons plasma levels are not clinically
useful.
o No specific lab work (CBC, electrolyte, urinalysis) is
needed unless otherwise indicated.
o Obtain baseline pulse oximetry or arterial blood gas
analysis.
|
| Treatment Overview: |
SUMMARY EXPOSURE
o Monitor EKG and vital signs carefully. Cardiopulmonary
resuscitation may be necessary.
ORAL EXPOSURE
o These substances may cause frostbite to the upper airway
and gastrointestinal tract after ingestion. Administer
oxygen and manage airway as clinically indicated.
Emesis, activated charcoal, and gastric lavage are not
recommended.
INHALATION EXPOSURE
o MONITOR ECG and VITAL SIGNS carefully. Cardiopulmonary
resuscitation may be necessary. AVOID CATECHOLAMINES.
o PROVIDE A QUIET CALM ATMOSPHERE to prevent adrenaline
surge if the patient is seen before the onset of cardiac
arrhythmias. Minimize physical exertion.
o MONITOR pulse oximetry or arterial blood gases.
o Provide symptomatic and supportive care.
o These substances may cause frostbite of the upper airway
with the potential for severe edema. Administer oxygen
and manage airway early in patients with evidence of
upper airway injury.
o PULMONARY EDEMA (NONCARDIOGENIC): Maintain ventilation
and oxygenation and evaluate with frequent arterial
blood gas or pulse oximetry monitoring. Early use of
PEEP and mechanical ventilation may be needed.
EYE EXPOSURE
o DECONTAMINATION: Irrigate exposed eyes with copious
amounts of tepid water for at least 15 minutes. If
irritation, pain, swelling, lacrimation, or photophobia
persist, the patient should be seen in a health care
facility.
o Ophthamologic consultation should be obtained in any
symptomatic patients.
DERMAL EXPOSURE
o DECONTAMINATION: Remove contaminated clothing and wash
exposed area thoroughly with soap and water. A
physician may need to examine the area if irritation or
pain persists.
o If frostbite has occurred, refer to dermal treatment in
the main body of this document for rewarming.
|
| Range of Toxicity: |
o Freons are very toxic when inhaled in high concentrations
and/or for extended periods. At lower concentrations or
brief exposure, freons may cause transient eye, nose, and
throat irritation. There is significant interpatient
variation and it is difficult to predict which patient
will exhibit symptoms following exposure.
|
Antidote and Emergency Treatment:
IF INHALATION OCCURS, EPINEPHRINE OR OTHER SYMPATHOMIMETIC AMINES & ADRENERGIC
ACTIVATORS SHOULD NOT BE ADMIN SINCE THEY WILL FURTHER SENSITIZE HEART TO DEVELOPMENT
OF ARRHYTHMIAS. /FLUOROCARBONS/
Patients with fluorohydrocarbon poisoning should not be given epinephrine
(Adrenalin) or similar drugs because of the tendency of fluorohydrocarbon to
induce cardiac arrhythmia, including ventricular fibrillation. /Fluorohydrocarbons/
Animal Toxicity Studies:
Evidence for Carcinogenicity:
Evaluation: There is inadequate evidence in humans for the carcinogenicity
of chlorodifluoromethane. There is limited evidence in experimental animals
for the carcinogenicity of chlorodifluoromethane. Overall evaluation: Chlorodifluoromethane
is not classifiable as to its carcinogenicity in humans (Group 3).
Non-Human Toxicity Excerpts:
Since FC 22 is a high pressure fluorocarbon, it is more appropriate to make
a comparison with another high pressure compound, for example FC 12. Both fluorocarbons
cause early respiratory depression, bronchoconstriction, tachycardia, myocardial
depression, & hypotension in approximately equivalent concn (5 to 10%) in
dogs & monkeys. The difference between the two high pressure fluorocarbons
is that FC 22 does not induce cardiac arrhythmia in the monkey, although it
sensitizes the heart to epinephrine in the mouse, & that FC 22 does not
decrease pulmonary compliance in the monkey.
... CARDIAC SENSITIZATION DID NOT OCCUR IN DOGS EXPOSED TO FC-22 AT 25,000
PPM ALTHOUGH POSITIVE RESPONSE COULD BE EVOKED EXPERIMENTALLY AT 50,000 PPM.
IN RHESUS MONKEYS (M MULATTA), INHALATION OF 10-20% CONCN OF FREON 22 INCREASED
THE PULMONARY RESISTANCE OR BRONCHOCONSTRICTION.
... GUINEA PIGS SHOWED DEFINITE NERVOUS SYSTEM RESPONSE TO CONCN OF 16% BY
VOL IN AIR, OVER PERIOD OF 55 MIN. THEY SHOWED TREMORS & CONVULSIVE MOVEMENTS
BUT RECOVERED ON REMOVAL. AT 40%, THEY SHOWED TREMORS & WERE HELPLESS OVER
A PERIOD OF 2.5 HR BUT RECOVERED ... AT CONCN OF 58%, DEATH OCCURRED IN 8 MIN.
IN ACUTE, 2 HR EXPOSURES ... CONCN OF 75,000 TO 100,000 PPM PRODUCED EXCITATION
AND/OR CHANGES IN EQUILIBRIUM IN BOTH RATS AND GUINEA PIGS. /CNS DEPRESSION/
... OCCURRED AT 200,000 PPM AND MORTALITY RESULTED AT 300,000 AND 400,000 PPM.
... MICE /EXPOSED/ FOR 2-HR PERIODS ... TOLERATED ... /A MAXIMUM/ CONCN ...
/OF/ 1120 MG/L OF AIR (320,000 PPM), WHILE THE MINIMUM FATAL LEVEL WAS 1300
MG/L (370,000 PPM). THE MINIMUM CONCN CAPABLE OF ALTERING REFLEX RESPONSE IN
RABBITS VARIED BETWEEN 40-70 MG/L (11,000-20,000 PPM). /IN GUINEA PIGS/ ...
2-HR EXPOSURES AT APPROXIMATELY 200,000 PPM, THE HIGHEST LEVEL TESTED, DID NOT
CAUSE DEATH; HOWEVER, 50,000 PPM PRODUCED MILD CLINICAL CHANGES & MINIMAL
EFFECTS WERE NOTED AT 25,000 PPM.
In a 10-month experiment ... rats, mice, and rabbits /were exposed/ for 6
hours daily except Sunday at a concentration of 50 mg/L FC-22 (14,000 ppm);
rats and mice also inhaled 7 mg/L (2000 ppm) daily for 10 months. The 50-mg/L
exposures produced alterations in body weight, physiological endurance, and
hematological characteristics; pathological changes were noted in the lungs,
CNS, heart, liver, kidneys, and spleen. No effects were noted in animals exposed
at the 7-mg/L concentration.
COMMERCIAL PREPARATIONS OF FREON 22 WERE MUTAGENIC TO SALMONELLA TYPHIMURIUM
IN AMES ASSAY & EFFECT WAS NOT DEPENDENT ON PRESENCE OF RAT LIVER HOMOGENATE.
SIMILAR MUTAGENIC ACTIVITY OF A PURIFIED SAMPLE OF MONOCHLORODIFLUOROMETHANE
INDICATED THAT THE EFFECT OF COMMERCIAL FREON 22 WAS NOT DUE TO THE PRESENCE
OF IMPURITIES.
BASED ON EXPERIMENTS WITH RATS, MICE, DOGS, & MONKEYS, MONOCHLORODIFLUOROMETHANE
WAS CLASSIFIED AS PROPELLANT WITH INTERMEDIATE TOXICITY, CLASS 3.
EARLY ANIMAL ... EXPERIENCE INDICATED THAT HIGH VAPOR CONCN (EG, 20%) MAY
CAUSE CONFUSION, PULMONARY IRRITATION, TREMORS & RARELY COMA, BUT THAT THESE
EFFECTS WERE GENERALLY TRANSIENT & WITHOUT LATE SEQUELAE. /FLUOROCARBON
REFRIGERANTS & PROPELLANTS/
On the basis of early inhalation experiments in guinea pigs & rats, FC
22 was shown to be two to three times less toxic than FC 11. More recent comparative
studies indicate an eight- to ten-fold difference in cardiotoxicity in mice
& dogs.
... A 4 wk study /was conducted/ in which rats, guinea pigs, dogs, & cats
were exposed at 50,000 ppm FC-22. Twenty exposures of 3.5 hr each produced no
clinical, biochemical, or pathological effects.
The toxicological effect of fluorocarbon-22 was studied using mice and rabbits.
The following symptoms were observed during continuous inhalation in sequence
as time proceeded: reeling, weakness of forelegs, falling down, flow of mucous
fluid from mouth and nose, mydriasis and lacrimation, violent movement of body
and extremities and cyanosis. The lethal concn (LC50) for 30 min exposure in
mice was 27.7% and the threshold concn for death in rabbits was about 30%. Blood
concn was in direct proportion to inhaled concn. The cause of death was thought
to be respiratory insufficiency.
Adult male Sprague-Dawley rats (nine weeks old) were exposed to 50,000 ppm
Freon 22, five hr/day for eight weeks. The control group received filtered air
at an identical flow rate. At the end of the eight week exposure period, body
and organ weights, hematology, blood chemistry, plasma gonadotropins, and fertility
parameters were not significantly different from controls, with the exception
of serum cholesterol levels, which were slightly higher, and glucose and triglyceride
levels which were lower. The weight of coagulating glands was also lower than
those of controls, but did not interfere with fertility function.
Two short-term in vitro tests for mutagenicity (Salmonella reverse mutation
and BHK21 cell transformation) were conducted on a series of fluorocarbons.
Chlorodifluoromethane was positive in one or both of the tests and could be
considered potentially carcinogenic to animals. Rats were dosed for 1 yr by
gavage 5 days a week with chlorodifluoromethane in corn oil at a single dosage
of 300 mg/kg. The animals were observed until week 125 with detailed necropsy
at termination. Chlorodifluoromethane did not induce tumors.
The relative potency of effect of a wide range of halogenated and unsubstituted
hydrocarbons /including chlorodifluoromethane/ on the central nervous system
(CNS) and heart of experimental animals was determined. The chemicals used caused
stimulation or depression of the rat CNS after 10 min inhalation at 0.24-80%
(vol/vol), and cardiac sensitization in dogs after 5 min inhalation at 0.12-80%
(vol/vol).
Ninety-day studies, conducted with 6 fluorocarbons including chlorodifluoromethane,
showed that the lowest toxic concn were greater than 5,000 ppm when admin to
beagle dogs. With rats, the lowest toxic concn were greater than 10,000 ppm.
Admin took place on 90 consecutive days for 6 hr/day.
Groups of 80 male & 80 female Alderley Park Swiss-derived mice (age unspecified)
were exposed by inhalation to 0 (2 groups), 1000, 10,000 or 50,000 ppm (0, 3540,
35,400 or 177,000 mg/cu m) chlorodifluoromethane (CFC 22; purity, > 99.8%)
for 5 hr/day on 5 days/wk for up to 83 (males) or 94 (females) weeks, by which
time approx 80% of animals had died. There was no significant increase in the
overall incidence of benign or malignant tumors in treated animals compared
to concurrent controls. A small but statistically significant dose-related increase
(p= 0.006) in the incidence of hepatocellular carcinomas was observed in males
(control, 0/74 & 1/77; low-dose, 0/78; mid-dose, 3/80; high-dose, 4/80).
The tumor incidences in treated groups were all within the range of those in
historical controls (2-10%) for this strain of mouse.
Groups of 80 male and 80 female Alderley Park Wistar-derived rats (age unspecified)
were exposed by inhalation to 0 (2 groups), 1000, 10,000 or 50,000 ppm (0, 3540,
35,400 or 177,000 mg/cu m) chlorodifluoromethane (CFC 22; purity >99.8%)
for 5 hr/day, on 5 days/wk for up to 118 (females) or 131 (males) wk, by which
time approx 80% of animals had died. Body-wt gain was reduced in high-dose males
up to wk 80. Treatment did not affect number of animals with benign tumors.
Among males, the proportions of animals with malignant tumors were higher in
treated groups (controls, 16/80 & 18/80; low-dose, 27/80; mid-dose, 22/80;
high-dose, 33/80), due primarily to increases in incidences of fibrosarcomas
(controls, 5/80 & 7/80; low-dose, 8/80; mid-dose, 5/80; high-dose, 18/80).
The numbers of animals in which such tumors involved the salivary glands were,
1, 0, 1, 0 & 7, respectively. The increase in the overall incidence of fibrosarcomas
occurred between weeks 105 & 130. In addition, 4 high-dose males had Zymbal-gland
tumors, whereas no such tumor was found in males of the other groups. No increased
incidence of malignant tumors was observed in treated females.
... Mild liver changes were observed in rabbits exposed to 6% (212 g/cu m)
... for 5 hr/day on 5 days/wk for 8-12 wk; one of 14 rabbits developed supraventricular
arrhythmia.
CD rats were exposed to 0, 100, 1000 or 50,000 ppm (0, 0.354, 3.54 or 177
g/cu m) ... for 6 hr/day on days 6-15 of gestation. About 1/2 of the fetuses
were selected for detailed histological observations of the eye and related
structures. There were 646 rats (> 6000 fetuses) in the control group &
418 (> 4000 fetuses) in each exposure group. The highest dose level induced
maternal (decreased body-weight gain) and fetal (slightly reduced body weight)
toxicity and elevated the incidence of anophthalmia. The incidence of litters
containing a fetus with anophthalmia increased from 1.65 per thousand litters
in the control group to 15.67 per thousand at 50,000 ppm (177 g/cu m).
In a ... study in rabbits ... groups of 14-16 New Zealand rabbits were exposed
by inhalation to 0, 100, 1000 or 50,000 ppm (0, 0.354, 3.54 or 177 g/cu m) chlorodifluoromethane
for 6 hr/day during days 6-18 of pregnancy. The high-dose level exerted maternal
toxicity (lowered weight gain) during the first 4 days of treatment, but no
other effect was noted in the does or fetuses.
Chlorodifluoromethane (20 mM soln generated 500 ml/min; 1:1 air) was tested
in assays for forward mutation in Schizosaccharmoyces pombe & for mitotic
gene conversion in Saccharomyces cerevisiae, in the presence & absence of
mouse-liver S10; no activity was shown in either test system. Chlorodifluoromethane
also gave negative results in host-mediated assay in CD-1 mice administered
a single dose of 816 mg/kg body weight in oil by gavage, in which S pombe or
S cerevisiae were injected into the venous orbital sinus & incubated for
5 or 15 hr before harvesting and scoring. (The Working Group noted that the
site of recovery of the cells was not indicated.)
... /There was an/ increase in mutation frequency in Salmonella typhimurium
TA 100 exposed to a concn of 50% in air for 24 hr (details not given) .... Chlorodifluoromethane
was tested in 2 studies of dominant lethal mutations in mice, in which male
mice were exposed to various concn (10 to 100,000 ppm; 35.4 to 354,000 mg/cu
m) for 6 hr/day for 5 consecutive days. No consistent time- or treatment-related
effect was observed.
Groups of 60 male and 60 female Swiss mice, nine weeks of age, were exposed
by inhalation to 0, 1000 or 5000 ppm (0, 3540 or 17700 mg/cu m) chlorodifluoromethane
(FC 22; purity, 99.98%) for 4 hr per day on five days per week for 78 weeks.
The animals were kept under observation until spontaneous death (survival unspecified).
Full necropsy was performed on all animals. No effects were found on survival
or body weight. No difference related to treatment was found in the incidence
of benign or malignant tumors.
Groups of 60 male and 60 female Sprague Dawley rats, eight weeks of age, were
exposed by inhalation to 0, 1000 or 5000 ppm (0, 3540 or 17700 mg/cu m) chlorodifluoromethane
(FC 22; purity, 99.98%) for 4 hr per day on five days per week for 104 weeks.
Full necropsy was performed on all animals. No effects were found on survival
or body weight. No difference related to treatment was found in the incidence
of benign or malignant tumors.
Chlorodifluoromethane causes malformations of the eyes of fetal rats, but
has no reproductive effects in male rats and does not cause prenatal toxicity
in rabbits following exposure by inhalation.
Chlorodifluoromethane is mutagenic to Salmonella typhimurium but it did not
induce either mutation or gene conversion in Saccharomyces cerevisiae.
Non-Human Toxicity Values:
LC50 Mouse 30 min 27.7%
TSCA Test Submissions:
Oncogenicity was evaluated in male and female Alderley Park rats (80/sex/group)
exposed to chlorodifluoromethane via inhalation at 0 (2 groups), 1000, 10,000
and 50,000 ppm for 5 hrs/day, 5 days/week for 27-30 months. The only reported
finding of significance was an increase in the incidence of malignant neoplasms,
due mainly to fibrosarcoma of the salivary gland in both sexes at 50,000 ppm.
The incidence of these tumors was significant only after 25 months. This preliminary
report did not contain information concerning the histopathological results
of the study.
Oncogenicity was evaluated in male and female Alderley Park mice (80/sex/group)
exposed to chlorodifluoromethane via inhalation at 0 (2 groups), 1000, 10,000
and 50,000 ppm for 5 hrs/day, 5 days/week for 27-30 months. There was no increase
in overall tumor incidence or significant increase in neoplasms (benign or malignant)
observed between exposed animals and controls. This preliminary report did not
contain information concerning the histopathological results of the study.
Metabolism/Pharmacokinetics:
Metabolism/Metabolites:
Approx 0.1 and 0.06% of an inhaled dose was recovered as (14)C-carbon dioxide
after exposure of rats to 500 & 10,000 ppm (1.77 & 35.4 g/cu m) (14)C-chlorodifluoromethane,
respectively, for 15-24 hr by inhalation. The amount of radioactivity excreted
in the urine was approx 0.03 & 0.01% of the inhaled doses, respectively.
Similar findings have been reported recently, indicating that there is little
or no metabolism of chlorodifluoromethane in rats. After incubation of (36)Cl-chlorodifluoromethane
with Aroclor-induced rat-liver homogenates, no release of chloride was detected.
Chlorodifluoromethane inhaled by male Wistar rats at a concentration of 160
ppm (566 mg/cu m) underwent no detectable metabolism and prior treatment of
rats with either DDT or phenobarbital did not stimulate its metabolic transformation.
Absorption, Distribution & Excretion:
... MAIN FACTOR AFFECTING FATE OF FLUOROCARBONS IS BODY FAT, WHERE THEY ARE
CONCENTRATED & SLOWLY RELEASED INTO BLOOD AT CONCN THAT SHOULD NOT CAUSE
ANY RISK OF CARDIAC SENSITIZATION. /FLUOROCARBONS/
Fluorocarbon-22 was studied in mice and rabbits. Blood concn was in direct
proportion to inhaled concn. The concn in fat was greater than in other tissues
after prolonged inhalation. When inhalation was short, the concn in fat was
less than in other tissues.
THERE IS A SIGNIFICANT ACCUMULATION OF FLUOROCARBONS
IN BRAIN, LIVER & LUNG COMPARED TO BLOOD LEVELS, SIGNIFYING A TISSUE DISTRIBUTION
OF FLUOROCARBONS SIMILAR TO THAT OF CHLOROFORM. /FLUOROCARBONS/
Absorption of fluorocarbons is much lower after oral ingestion (35-48 times)
than after inhalation. ... The lung generally have the highest fluorocarbon
concn on autopsy. /Fluorocarbons/
Chlorodifluoromethane is very rapidly cleared from the blood of rats and rabbits
exposed by inhalation. Little distribution to tissues or metabolism occurs in
rats, with recoveries from expired air as CO2 in 15-24 hr and in the urine,
being about 0.1% and 0.02% of the dose, respectively.
Two groups of three male volunteers were exposed by inhalation to chlorodifluoromethane
at either 327 or 1833 mg/cu m for 4 hr. The average maximal blood concentrations
were 0.25 and 1.36 ug/ml, respectively, and were achieved within 1 hr of the
beginning of exposure. The average blood/air partition coefficients for chlorodifluoromethane
towards the end of the exposure period were 0.82 and 0.76, respectively, and
the fat/air partition coefficients were 7.7 and 8.1. Thus, the fat/blood partition
coefficient was estimated to be approximately 10. Three phases for the elimination
of chlorodifluoromethane in breath were identified, with estimated half-lives
of 0.005, 0.2 and 2.6 hr. An average of 2.1% of the inhaled chlorodifluoromethane
was recovered from the exhaled air over 26 hr and minimal amounts were found
in urine. Minimal changes in the fluoride
concentration in urine were observed, which is consistent with a low degree
of metabolism.
Biological Half-Life:
Rats were exposed by inhalation to 10,000 and 50,000 ppm (35.4 & 177 g/cu
m) chlorodifluoromethane. The half-life for the clearance of chlorodifluoromethane
from the blood, immediately after termination of exposure, was approx 3 min.
Three phases for the elimination of chlorodifluoromethane in breath were identified,
with estimated half-lives of 0.005, 0.2 and 2.6 hr.
Interactions:
IF INHALATION OCCURS, EPINEPHRINE OR OTHER SYMPATHOMIMETIC AMINES & ADRENERGIC
ACTIVATORS SHOULD NOT BE ADMIN SINCE THEY WILL FURTHER SENSITIZE HEART TO DEVELOPMENT
OF ARRHYTHMIAS. /FLUOROCARBONS/
Pharmacology:
Interactions:
IF INHALATION OCCURS, EPINEPHRINE OR OTHER SYMPATHOMIMETIC AMINES & ADRENERGIC
ACTIVATORS SHOULD NOT BE ADMIN SINCE THEY WILL FURTHER SENSITIZE HEART TO DEVELOPMENT
OF ARRHYTHMIAS. /FLUOROCARBONS/
Environmental Fate & Exposure:
Environmental Fate/Exposure Summary:
Chlorodifluoromethane's production and use in aerosols, blowing agents, refrigeration,
air conditioning, and thermoset foams may result in its release to the environment
through various waste streams. If released to air, a vapor pressure of 7,250
mm Hg at 25 deg C indicates chlorodifluoromethane will exist solely in the gas-phase
in the ambient atmosphere. Gas-phase chlorodifluoromethane will be degraded
very slowly in the atmosphere by reaction with photochemically-produced hydroxyl
radicals; the half-life for this reaction in air is estimated to be 9.4 yrs.
As a result of its long half-life, a substantial fraction of chlorodifluoromethane
will slowly diffuse to the stratosphere. Once in the upper stratosphere, it
is dissociated through photolysis, reaction with hydroxyl radical and excited
atomic oxygen resulting in the release of chlorine. These chlorine atoms then
become part of a catalytic process that contributes to the destruction of the
ozone layer. In the troposphere, however, chlorodifluoromethane is not expected
to undergo photolysis since it does not absorb light >290nm. Since chlorodifluoromethane
is a gas under ambient conditions, most of the chemical released on soils will
volatilize rapidly. Any chlorodifluoromethane which remains on soil will have
a high potential for leaching based on its estimated Koc of 35. If released
into water, chlorodifluoromethane is not expected to adsorb to suspended solids
and sediment based upon the estimated Koc. Based on chlorodifluoromethane's
low biodegradability under both aerobic and anaerobic conditions, it is not
expected to biodegrade in either soil or water. Volatilization from water surfaces
is expected to be an important fate process based upon this compound's Henry's
Law constant. An estimated BCF of 1 suggests the potential for bioconcentration
in aquatic organisms is low. The chlorodifluoromethane hydrolysis rate is very
low, <0.01 g/L-yr at 30 deg C, and is not expected to be an important degradation
pathway in the environment. Occupational exposure to chlorodifluoromethane may
occur through inhalation and dermal contact with this compound at workplaces
where chlorodifluoromethane is produced or used. Monitoring data indicate that
the general population may be exposed to chlorodifluoromethane via inhalation
of ambient air and from leaky refrigeration units containing chlorodifluoromethane.
(SRC)
Probable Routes of Human Exposure:
THERE ARE ISOLATED REPORTS OF POISONING FROM EXPOSURE TO FLUOROCARBON PROPELLANTS
& SOME STUDIES SHOWING A HIGHER INCIDENCE OF CORONARY HEART DISEASE AMONG
HOSPITAL PERSONNEL & REFRIGERANT MECHANICS EXPOSED TO FLUOROCARBONS. ADDITIONAL
INVESTIGATION IS REQUIRED TO ESTABLISH CAUSAL RELATIONSHIP BETWEEN FLUOROCARBONS
& CARDIOVASCULAR & BRONCHOPULMONARY DISEASES AMONG EXPOSED WORKERS.
THE HIGH INCIDENCE OF CANCER AMONG HOSPITAL PERSONNEL REPEATEDLY EXPOSED TO
FLUORINE-CONTAINING GENERAL ANESTHETICS RAISES A FUNDAMENTAL NEED TO EXAMINE
OTHER FLUOROCARBON-EXPOSED WORKERS FOR SIMILAR EFFECTS. /FLUOROCARBONS/
...Exposure in chemical plant operations and production is generally low but
highly variable, and may be high in areas without adequate ventilation. Cylinder
packers and shippers have occasional high exposure. Exposure during tank farm
operations, and tank and drum filling, may exceed the threshold limit value.
Tank truck and tank car fillers have potentially high exposure, which may be
intermittent with the occurrence of accidents. Maintenance operators, laboratory
analysts, and supervisory personnel have low exposure. The highest exposure
in the plant occurs with venting of gases from returnable cylinders. The formation
of high-temperature thermal decomposition products may occur during storage.
NIOSH (NOES Survey 1981-1983) has statistically estimated that 149,149 workers,
including 8,054 women, are potentially exposed to chlorodifluoromethane in the
USA(1). Occupational exposure to chlorodifluoromethane may occur through inhalation
and dermal contact with this compound at workplaces where chlorodifluoromethane
is produced or used(SRC). Monitoring data indicate that the general population
may be exposed to chlorodifluoromethane via inhalation of ambient air(2,3) from
and leaky refrigeration units containing chlorodifluoromethane(4).
In one study, workers in a fluorocarbon shipping and packaging plant were
exposed to 4.7-13.5 ppm of chlorodifluoromethane(1).
Body Burden:
A pilot study of volatile organic chemicals in mother's milk found that two
of eight samples of milk obtained from women in 4 urban areas in the United
States contained chlorodifluoromethane; the levels were not quantified(1).
Two simultaneous accidental, lethal exposures to chlorodifluoromethane alone
were associated with concentrations (in ul/ml) of the chemical in body fluid
samples taken 16 hr after death of: blood, 37.1 and 26.0; urine, 1.7 and 0.9;
vitreous humor, 1.0 and 0.7.
Artificial Pollution Sources:
Of the estimated 941 million kg produced throughout the world between 1967
and 1977, approx 44% (418 million kg) has been released to the atmosphere by
1978 (Panel on Stratospheric Chemistry and Transport, 1979). Emissions ... to
the troposphere in 1978 were calculated to be 50 million kg/yr (21 million kg
per yr chlorine equivalents), with 40% reaching the stratosphere. In 1972, the
atmospheric release rate in the northern hemisphere as a result of human activity
was estimated to be 33 million kg/yr.
Chlorodifluoromethane's production and use in aerosols, blowing agents, refrigeration,
air conditioning, and thermoset foams(1) may result in its release to the environment
through various waste streams. The major use of chlorodifluoromethane, however,
is in refrigeration and air conditioning applications which accounts for 90%
of reported sales. When chlorodifluoromethane is used in refrigeration, there
is a delay of six to seven years between its production and its release into
the atmosphere(2). Based on information from producers, approximately 2.5% of
chlorodifluoromethane is released directly into the environment during packaging
operations and from plant vents(1). In operations in which chlorodifluoromethane
is used as a chemical intermediate, approximately 1% is lost during chemical
processing(1). The use of chlorodifluoromethane has been increasing markedly
since it is one of the few fluorocarbons currently not restricted by the Montreal
Protocol for the protection of the ozone layer. However, by the year 2020, the
consumption of all HCFCs will be phased down at least by 99.5% which will include
chlorodifluoromethane(3). Annual worldwide production (in X10+6 kg) of chlorodifluoromethane
from 1970 to 1994 were as follows: 56.1 (1970), 75.0 (1975), 126.3 (1980), 153.4
(1985), 213.7 (1990), and 239.4 (1994)(1,4). Annual worldwide release (in X10+6
kg) to the environment, based on production data, are: 41.4 (1970), 65.7 (1975),
104.3 (1980), 137.2 (1985), 195.2 (1990), and 218.9 (1994)(1,4). In the United
States alone, 82,000 tons of chlorodifluoromethane was released into the environment
in 1990(4). The country with the second highest emission of chlorodifluoromethane
was the Russian Federation at 20,500 tons(2). Production surveys have indicated
that 90% of total production of chlorodifluoromethane was sold in the northern
hemisphere between 1980 to 1991(1).
Environmental Fate:
TERRESTRIAL FATE: Since chlorodifluoromethane is a gas(1) under ambient conditions,
most of the chemical released on land will volatilize rapidly. Any chlorodifluoromethane
which remains on soil will have a high potential(2) for leaching based on its
estimated Koc of 35(3). Based on chlorodifluoromethane's low biodegradability
under both aerobic and anaerobic conditions, it is not expected to biodegrade
in soils(4,5).
AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value
of 35(SRC), using a strucutre estimation method based on molecular connectivity
indices(2), indicates that chlorodifluoromethane is not expected to adsorb to
suspended solids and sediment(SRC). Volatilization from water surfaces is expected(3)
based upon a Henry's Law constant of 4.06X10-2 atm-cu m/mole(4). Using this
Henry's Law constant and an estimation method(3), volatilization half-lives
for a model river and model lake are 58 mins and 3.7 days, respectively(SRC).
Based on chlorodifluoromethane's low biodegradability under both aerobic and
anaerobic conditions, it is not expected to biodegrade in aqueous systems(4,5).
According to a classification scheme(6), an estimated BCF of 1(SRC), from its
log Kow of 1.08(7) and a regression-derived equation(8), suggests the potential
for bioconcentration in aquatic organisms is low. Hydrolysis in water is not
expected to be important due to chlorodifluoromethane's low rate of hydrolysis
(<0.01 g/L-yr)(9).
ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile
organic compounds in the atmosphere(1), chlorodifluoromethane, which has a vapor
pressure of 7,250 mm Hg at 25 deg C(2), is expected to exist in the gas phase
in the ambient atmosphere. Gas-phase chlorodifluoromethane is degraded in the
atmosphere by reaction with photochemically-produced hydroxyl radicals(SRC);
the half-life for this reaction in air is estimated to be 9.4 yrs(SRC), calculated
from its rate constant of 4.68X10-15 cu cm/molecule-sec at 25 deg C(3). As a
result of its long half-life, a substantial fraction of the chlorodifluoromethane
will slowly diffuse to the upper stratosphere. Once in the upper stratosphere,
it is dissociated through photolysis, reaction with hydroxyl radical and excited
atomic oxygen resulting in the release of chlorine at high altitudes(4). These
chlorine atoms then become part of a catalytic process that contributes to the
destruction of the ozone layer. In the troposphere, however, chlorodifluoromethane
is not expected to undergo photolysis since it does not absorb light >290nm(5).
Environmental Biodegradation:
AEROBIC: Chlorodifluoromethane, present at 1.69 mg/l, reached 0% of its theoretical
BOD in 4 weeks using an activated sludge inoculum at 2 mg/l and the Japanese
MITI test(1).
ANAEROBIC: Using a mixed culture of methanotrophic bacteria collected from
an aquifer, a second order rate constant of 0.014 L/mg-cell-day was obtained
for chlorodifluoromethane(1). Assuming typical microbial densities in soil and
marine environments of 1X10+6 to 1X10+7 organisms/cu cm of soil and water, respectively,
of which 1% are methanotropes, first order rate rates of 1X10-10 to 1X10-9 1/sec
are obtained, from which a half-life of 22 yrs was calculated(SRC).
Environmental Abiotic Degradation:
The rate constant for the vapor-phase reaction of chlorodifluoromethane with
photochemically-produced hydroxyl radicals is 4.68X10-15 cu cm/molecule-sec
at 25 deg C(1). This corresponds to an atmospheric half-life of approximately
9.4 yrs at an atmospheric concn of 5X10+5 hydroxyl radicals per cu cm(2). As
a result of its long half-life, a substantial fraction of the chlorodifluoromethane
will slowly diffuse to the upper stratosphere. Once in the upper stratosphere,
it is dissociated through photolysis, reaction with hydroxyl radical and excited
atomic oxygen resulting in the release of chlorine at high altitudes(3). These
chlorine atoms then become part of a catalytic process that contributes to the
destruction of the ozone layer. The estimated tropospheric half-life of chlorodifluoromethane
is 9.1 years(4) while the estimated total lifetime of chlorodifluoromethane
in the atmosphere ranges from 13.6 to 15 years(5,6). Chlorodifluoromethane is
not expected to undergo photolysis in the troposphere or in surface waters since
it does not absorb light >290nm(7). The rate of chlorodifluoromethane hydrolysis
is very low, <0.01 g/L-yr) at 30 deg C, and is not expected to be an important
degradation pathway in the environment(8).
Environmental Bioconcentration:
An estimated BCF of 1 was calculated for chlorodifluoromethane(SRC), using
a log Kow of 1.08(1) and a regression-derived equation(2). According to a classification
scheme(3), this BCF suggests the potential for bioconcentration in aquatic organisms
is low.
Soil Adsorption/Mobility:
Since chlorodifluoromethane is a gas(1) under ambient conditions, most of
the chemical released on soil will volatilize rapidly. Any chlorodifluoromethane
which remains on soil will have a high potential(2) for leaching into groundwater
based on its estimated Koc of 35(3). However, chlorodifluoromethane's high volatility
should effectively reduce this potential.
Volatilization from Water/Soil:
The Henry's Law constant for chlorodifluoromethane is 4.06X10-2 atm-cu m/mole(1).
This Henry's Law constant indicates that chlorodifluoromethane is expected to
volatilize rapidly from water surfaces(2). Based on this Henry's Law constant,
the volatilization half-life from a model river (1 m deep, flowing 1 m/sec,
wind velocity of 3 m/sec)(2) is estimated as 58 minutes(SRC). The volatilization
half-life from a model lake (1 m deep, flowing 0.05 m/sec, wind velocity of
0.5 m/sec)(2) is estimated as 3.7 days(SRC). Chlorodifluoromethane's Henry's
Law constant(1) indicates that volatilization from moist soil surfaces may occur(SRC).
The potential for volatilization of chlorodifluoromethane from dry soil surfaces
is expected(SRC) based upon a vapor pressure of 7,250 mm Hg(3).
Effluent Concentrations:
Trace volatile organic compounds were monitored in landfill gas at 7 U.K.
waste disposal facilities from 1994 to 1995(1). Concns of chlorodifluoromethane
ranged from <0.5 mg/cu m to 404 mg/cu m. The presence of chlorodifluoromethane
in landfill gas is expected to be due to direct volatilization from plastic
foam, aerosol propellants, and refrigerators. Based on emission rates monitored
in 1995 from the U.K., the total global emission of chlorodifluoromethane is
1.4X10+8 kg/year(1). Dust samples from a municipal waste incinerator located
in Hamburg, Germany were analyzed for chlorodifluoromethane concns(2). The study
determined that chlorodifluoromethane concns ranged from <0.005 to 0.89 mg/kg
waste. When municipal waste was added to a laboratory anaerobic digester, levels
of chlorodifluoromethane were measured in both the gas and leachate. Maximum
chlorodifluoromethane concns were 385 mg/N cu m in gas samples and 0.9 mg/l
in leachate(2).
Atmospheric Concentrations:
Analysis of the atmospheric burden of chlorodifluoromethane by gas chromatography/mass
spectrometry gave an avg global concn of approx 45.0 parts per trillion (159.0
ng/cu m) in mid-1979; the northern hemisphere ambient concn was 50.0 parts per
trillion (177.0 ng/cu m) and the southern hemisphere, 42 parts per trillion
(149.0 ng/cu m). In May 1982, the avg atmospheric concn of chlorodifluoromethane
in the lower troposphere measured over Point Barrow, Alaska was 73.2 parts per
trillion (259.0 ng/cu m).
A study ... showed that levels of chlorodifluoromethane in air samples (31.0-55.0
parts per trillion (110-195 ng/cu m)) collected over the state of Washington
were not elevated 2 days after eruption of the Mount St Helens volcano.
Chlorodifluoromethane is the seventh most common halocarbon in the atmosphere,
having an average concentration of 60 parts per trillion(1). Because of its
long atmospheric half-life, chlorodifluoromethane will disperse over the globe
and accumulate in the atmosphere. Its concentration levels, removed from local
sources, will be similar at different locations and will increase with time.
In January 1980, the concentration of chlorodifluoromethane in the remote Pacific
Northwest and the South Pole was 63 and 45 parts per trillion, respectively(2).
At Barrows Alaska, the concentration was highest in January, 62.5 parts per
trillion and lowest in July, 55.3 parts per trillion(3). The median concentration
of chlorodifluoromethane at two rural/remote sites and four urban/suburban sites
in the United States from the 1970s was 14 and 25 parts per trillion, respectively(4).
The maximum concentration reported at the urban/suburban sites was 150 parts
per trillion(4).
URBAN/SUBURBAN: Monitoring studies have indicated that the global mean ground-level
concn of chlorodifluoromethane have increased 7.3% per year between mid-1987
through 1992(1). Similar increases were observed over Jungfraujoch Switzerland
from 1986 to 1992 and in Kitt Peak, Arizona from 1980 to 1992 where chlorodifluoromethane
concns increased 7.0% per year at both locales(2). Over Table Mountain California,
chlorodifluoromethane concns increased 6.7% from 1985 to 1990(3). The average
global concn of chlorodifluoromethane ranges from 101-115 parts/trillion(3).
Atmospheric concns of chlorodifluoromethane were measured above Cape Grim, Tasmania
from 1978 to 1996(4). Concns (parts/trillion) were: 31.23 (1978), 44.85 (1981),
55.39 (1984) 69.20 (1987), 89.91 (1990), 101.82 (1993) and 118.36 (1996). Chlorodifluoromethane
was also measured above La Jolla, California from 1992 to 1996. At this location,
concns (parts/trillion) were: 112.86 (1992), 118.19 (1993), 122.32 (1994), 133.95
(1995), and 136.41 (1996). A global mean concn of 101.8 parts/trillion and interhemispheric
difference of 13 parts/trillion were determined for chlorodifluoromethane in
1992 from air collected in flasks from 7 remote sites(5).
Milk Concentrations:
A pilot study of volatile organic chemicals in mother's milk found that two
of eight samples of milk obtained from women in 4 urban areas in the United
States contained chlorodifluoromethane; the levels were not quantified(1).
Environmental Standards & Regulations:
TSCA Requirements:
Pursuant to section 8(d) of TSCA, EPA promulgated a model Health and Safety
Data Reporting Rule. The section 8(d) model rule requires manufacturers, importers,
and processors of listed chemical substances and mixtures to submit to EPA copies
and lists of unpublished health and safety studies. Chlorodifluoromethane is
included on this list.
Atmospheric Standards:
This action promulgates standards of performance for equipment leaks of Volatile
Organic Compounds (VOC) in the Synthetic Organic Chemical Manufacturing Industry
(SOCMI). The intended effect of these standards is to require all newly constructed,
modified, and reconstructed SOCMI process units to use the best demonstrated
system of continuous emission reduction for equipment leaks of VOC, considering
costs, non air quality health and environmental impact and energy requirements.
Chlorodifluoromethane is produced, as an intermediate or a final product, by
process units covered under this subpart.
Clean Water Act Requirements:
Toxic pollutant designated pursuant to section 307(a)(1) of the Clean Water
Act and is subject to effluent limitations. /Halomethanes/
Chemical/Physical Properties:
Molecular Formula:
C-H-Cl-F2
Molecular Weight:
86.47
Color/Form:
Colorless gas
Colorless gas ... [Note: Shipped as a liquefied compressed gas].
Odor:
Nearly odorless
Like carbon tetrachloride
... Faint, sweetish odor ...
Boiling Point:
-40.8 deg C @ 760 mm Hg
Melting Point:
-157.4 deg C
Critical Temperature & Pressure:
Critical temperature: 96.0 deg C; Critical pressure: 48.7 atm
Density/Specific Gravity:
1.194 @ 25 deg C
Heat of Combustion:
-6.5704X10+07 J/kmol
Heat of Vaporization:
101 BTU/lb= 55.9 cal/g= 2.34X10+5 J/kg
Octanol/Water Partition Coefficient:
log Kow= 1.08
Solubilities:
0.28 g/l water @ 77 deg F & 14.7 psia
0.14 g/l water @ 122 deg F & 14.7 psia
> 10% in acetone
> 10% in chloroform
> 10% in ethyl ether
Sol in ether, acetone, and chloroform
In water, 2770 mg/l @ 25 deg C
Spectral Properties:
Index of refraction: 1.256 @ 25 deg C
IR: 3701 (Sadtler Research Laboratories Prism Collection)
MASS: 132 (Atlas of Mass Spectral Data, John Wiley & Sons, New York)
Surface Tension:
1.5 N/cm @ -41 deg C
Vapor Density:
3 (Air = 1)
Vapor Pressure:
7,250 mm Hg @ 25 deg C
Viscosity:
0.23 mN/sec/sq m @ 25 deg C (liquid); 0.013 mN/sec/sq m @ 25 deg C (gas)
Other Chemical/Physical Properties:
1 MG/L= 282.6 PPM & 1 PPM= 3.54 MG/CU M @ 25 DEG C, 760 MM HG
Density at bp: 4.82 g/l (gas)
Ratio of specific heats of vapor (gas): 1.13 (est)
Dielectric constant: 6.11 @ 24 deg C; dipole moment: 1.4 debyes (gas)
Enthalpy @ 25 deg C: -115.6 kcal/mole (gas); Gibbs (free) energy of formation
@ 25 deg C: -108.1 kcal/mole (gas); entropy @ 25 deg C: 67.12 cal/deg/mole (gas);
heat capacity @ 25 deg C: 13.35 cal/deg/mole (gas)
Density: 1.41 @ -40 deg C (liquid)
VP: 201 kPa @ -25 deg C; 498 kPa @ 0 deg C; 1044 kPa @ 25 deg C; 1944 kPa
@ 50 deg C; 3317 kPa @ 75 deg C
Henry's Law constant= 4.06X10-2 atm-cu m/mole @ 22 deg C
Hydroxyl radical rate constant= 4.68X10-15 cu cm/molecule-sec @ 25 deg C
Ozone depletion potential=0.055 (CFC11=1)
Chemical Safety & Handling:
DOT Emergency Guidelines:
Fire or explosion: Some may burn, but none ignite readily. Containers may
explode when heated. Ruptured cylinders may rocket.
Health: Vapors may cause dizziness or asphyxiation without warning. Vapors
from liquefied gas are initially heavier than air and spread along ground. Contact
with gas or liquefied gas may cause burns, severe injury and/or frostbite. Fire
may produce irritating, corrosive and/or toxic gases.
Public safety: CALL Emergency Response Telephone Number. ... Isolate spill
or leak area immediately for at least 100 meters (330 feet) in all directions.
Keep unauthorized personnel away. Stay upwind. Many gases are heavier than air
and will spread along ground and collect in low or confined areas (sewers, basements,
tanks). Keep out of low areas. Ventilate closed spaces before entering.
Protective clothing: Wear positive pressure self-contained breathing apparatus
(SCBA). Structural firefighters' protective clothing will only provide limited
protection.
Evacuation: Large spill: Consider initial down wind evacuation for at least
500 meters (1/3 mile). Fire: If tank, rail car or tank truck is involved in
a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider
initial evacuation for 800 meters (1/2 mile) in all directions.
Fire: Use extinguishing agent suitable for type of surrounding fire. Small
fires: Dry chemical or CO2. Large fires: Water spray, fog or regular foam. Move
containers from fire area if you can do it without risk. Damaged cylinders should
be handled only by specialists. Fire involving tanks: Fight fire from maximum
distance or use unmanned hose holders or monitor nozzles. Cool containers with
flooding quantities of water until well after fire is out. Do not direct water
at source of leak or safety devices; icing may occur. Withdraw immediately in
case of rising sound from venting safety devices or discoloration of tank. ALWAYS
stay away from the ends of tanks. Some of these materials, if spilled, may evaporate
leaving a flammable residue.
Spill or leak: Do not touch or walk through spilled material. Stop leak if
you can do it without risk. Do not direct water at spill or source of leak.
Use water spray to reduce vapors or divert vapor cloud drift. If possible, turn
leaking containers so that gas escapes rather than liquid. Prevent entry into
waterways, sewers, basements or confined areas. Allow substance to evaporate.
Ventilate the area.
First aid: Move victim to fresh air. Call emergency medical care. Apply artificial
respiration if victim is not breathing. Administer oxygen if breathing is difficult.
Remove and isolate contaminated clothing and shoes. In case of contact with
liquefied gas, thaw frosted parts with lukewarm water. Keep victim warm and
quiet. Ensure that medical personnel are aware of the material(s) involved,
and take precautions to protect themselves.
Skin, Eye and Respiratory Irritations:
Vapor not irritating to eyes, nose, or throat.
Fire Potential:
Not flammable.
Fire Fighting Procedures:
If material involved in fire: Extinguish fire using agent suitable for type
of surrounding fire. (Material itself does not burn or burns with difficulty.)
Cool all affected containers with flooding quantities of water. Apply water
from as far a distance as possible.
Toxic Combustion Products:
Poisonous gases are produced when heated.
Explosive Limits & Potential:
Nonexplosive
Hazardous Reactivities & Incompatibilities:
/Incompatible with/ aluminum
... On contact with acids or acid fumes, they evolve highly toxic ... fumes.
/Chlorides/
In a dichlorodifluoromethane system, frictional wear exposed fresh metal surfaces
on an aluminum compressor impellor, causing an exothermic reaction which melted
much of the impellor. Later tests showed similar results ... with ... chlorodifluoromethane
... .
At elevated pressures, mixtures of the Refrigerant 22 gas with 50% of air
are combustible (though ignition is difficult) and a 6- to 8-fold pressure increase
may occur in closed systems if ignition occurs.
Alkalis, alkaline earth metals (e.g., powdered aluminum, sodium, potassium,
zinc).
Hazardous Decomposition:
Decomposition gases are toxic & irritating.
When heated to decomp ... they evolve highly toxic ... fumes of /hydrogen
chloride and hydrogen fluoride/.
ALL FLUOROCARBONS WILL UNDERGO THERMAL DECOMPOSITION WHEN EXPOSED TO FLAME
OR RED-HOT METAL. DECOMPOSITION PRODUCTS OF THE CHLOROFLUOROCARBONS WILL INCLUDE
HYDROFLUORIC & HYDROCHLORIC ACID ALONG WITH SMALLER AMOUNTS OF PHOSGENE
& CARBONYL FLUORIDE. THE LAST CMPD
IS VERY UNSTABLE TO HYDROLYSIS & QUICKLY CHANGES TO HYDROFLUORIC ACID &
CARBON DIOXIDE IN THE PRESENCE OF MOISTURE. /FLUOROCARBONS/
Protective Equipment & Clothing:
Rubber gloves; goggles.
... INDIVIDUAL BREATHING DEVICES WITH INDEPENDENT AIR SUPPLY WILL MINIMIZE
RISK OF INHALATION. LIFELINES SHOULD BE WORN WHEN ENTERING TANKS OR OTHER CONFINED
SPACES. /FLUOROCARBONS/
Wear appropriate personal protective clothing to prevent the skin from becoming
frozen from contact with the liquid or from contact with vessels containing
the liquid.
Wear appropriate eye protection to prevent eye contact with the liquid that
could result in burns or tissue damage from frostbite.
Quick drench facilities and/or eyewash fountains should be provided within
the immediate work area for emergency use where there is any possibility of
exposure to liquids that are extremely cold or rapidly evaporating.
Many of the fluorocarbons are good solvents of skin oil, so protective ointment
should be used. /Fluorocarbons/
Preventive Measures:
SUFFICIENT EXHAUST & GENERAL VENTILATION SHOULD BE PROVIDED TO KEEP VAPOR
CONCN BELOW RECOMMENDED LEVELS. /FLUOROCARBONS/
If material not involved in fire: Attempt to stop leak if without undue personnel
hazard.
Personnel protection: Avoid breathing vapors. Keep upwind. ... Do not handle
broken packages unless wearing appropriate personal protective equipment.
SRP: Local exhaust ventilation should be applied wherever there is an incidence
of point source emissions or dispersion of regulated contaminants in the work
area. Ventilation control of the contaminant as close to its point of generation
is both the most economical and safest method to minimize personnel exposure
to airborne contaminants.
Eye washer and instant shower facilities should be located near the work areas
where spills and splash hazards exist. /Fluorocarbons/
Shipment Methods and Regulations:
No person may /transport,/ offer or accept a hazardous material for transportation
in commerce unless that person is registered in conformance ... and the hazardous
material is properly classed, described, packaged, marked, labeled, and in condition
for shipment as required or authorized by ... /the hazardous materials regulations
(49 CFR 171-177)./
The International Air Transport Association (IATA) Dangerous Goods Regulations
are published by the IATA Dangerous Goods Board pursuant to IATA Resolutions
618 and 619 and constitute a manual of industry carrier regulations to be followed
by all IATA Member airlines when transporting hazardous materials.
The International Maritime Dangerous Goods Code lays down basic principles
for transporting hazardous chemicals. Detailed recommendations for individual
substances and a number of recommendations for good practice are included in
the classes dealing with such substances. A general index of technical names
has also been compiled. This index should always be consulted when attempting
to locate the appropriate procedures to be used when shipping any substance
or article.
Disposal Methods:
SRP: At the time of review, criteria for land treatment or burial (sanitary
landfill) disposal practices are subject to significant revision. Prior to implementing
land disposal of waste residue (including waste sludge), consult with environmental
regulatory agencies for guidance on acceptable disposal practices.
Because of the discovery of potential ozone decomposition in the stratosphere
by chlorodifluoromethane, the material should not be released to the environment
if it can be prevented. Material to be scrapped should be returned to the vendor,
or to licensed waste disposal company.
Occupational Exposure Standards:
Threshold Limit Values:
8 hr Time Weighted Avg (TWA) 1000 ppm
Excursion Limit Recommendation: Excursions in worker exposure levels may exceed
three times the TLV-TWA for no more than a total of 30 min during a work day,
and under no circumstances should they exceed five times the TLV-TWA, provided
that the TLV-TWA is not exceeded.
A4. A4= Not classifiable as a human carcinogen.
NIOSH Recommendations:
Recommended Exposure Limit: 10 Hr Time-Weighted Avg: 1000 ppm (3500 mg/cu
m).
Recommended Exposure Limit: 15 Min Short-Term Exposure Limit: 1250 ppm (4375
mg/cu m).
Manufacturing/Use Information:
Major Uses:
For Chlorodifluoromethane (USEPA/OPP Pesticide Code: 000015) there are 0 labels
match. /SRP: Not registered for current use in the
U.S., but approved pesticide uses may change periodically and so federal, state
and local authorities must be consulted for currently approved uses./
/Former/
Refrigerant; low-temperature solvent; fluorocarbon resins, especially tetrafluoroethylene
polymers
The azeotropic mixture (F-502) of chlorodifluoromethane/chloropentafluoroethane
(F-115) is used as a refrigerant, primarily in food display cases, ice makers,
home freezers & heat pumps.
Manufacturers:
DuPont, Hq, 1007 Market Street, Wilmington, DE 19898, (302) 774-1000; Subsidiary:
DuPont Fluoroproducts, Belle, West Virginia 26101, (304)357-1000; Production
site: Louisville, KY 40201
Elf Atochem North America, Inc, Hq, 2000 Market Street, 21st Floor, Philadelphia,
PA 19103-3222, (215) 419-7000; Subsidiary: Fluorochemicals Division, Calvert
City, KY 42029; Production site: Witchita, KA 67215
Honeywell, Hq, 101 Coumbia Road, P.O. Box 1057, Morristown, NJ 07962-1057,
(973) 455-2000; Subsidiary: Specialty Chemicals, Baton Rouge, LA 70805; Production
site: El Segundo, CA 90245
Methods of Manufacturing:
Reaction of chloroform with anhydrous hydrogen fluoride
with antimony chloride catalyst.
THE TRADITIONAL, LIQUID-PHASE PROCESS USES ANTIMONY PENTAFLUORIDE OR A MIXTURE
OF ANTIMONY TRIFLUORIDE AND CHLORINE AS CATALYSTS. THIS PROCESS IS BEING REPLACED
BY A CONTINUOUS VAPOR-PHASE PROCESS THAT EMPLOYS GASEOUS HYDROGEN FLUORIDE
IN THE PRESENCE OF CHROMIUM OXIDE OR HALIDE, FERRIC CHLORIDE, OR THORIUM TETRAFLUORIDE
CATALYSTS.
The most important commercial method for manufacturing /chlorofluoro carbons/
is the successive replacement of chlorine by fluorine using hydrogen fluoride
... chlorodifluoromethane is produced by reacting chloroform with HF
General Manufacturing Information:
Unlike other chlorofluorocarbons, chlorodifluoromethane is not currently used
to a large degree as a blowing agent for polyurethane resins or as an industrial
solvent, but these applications have been reported previously.
POLYMER OF PYROLYTIC DEHYDROCHLORINATION PRODUCT /POLYTETRAFLUOROETHYLENE/
IS USED FOR LINING COOKWARE, WIRE INSULATION, RUST PROOF COATINGS AND PAINTS
FOR BARNACLE-FREE BOAT HULLS
Chlorofluoroalkanes produced on an industrial scale are subject to stringent
standards ... impurities must not exceed the following limits (vol%): acids,
0; moisture, <0.001; higher-boiling fractions, <0.05; other gases, 2
Formulations/Preparations:
USEPA/OPP Pesticide Code 000015; Trade Names: Freon 22. /Former trade names/
Grade: technical; 99.9% pure
It is available as a liquified gas in an azeotropic mixture of 48.8% chlorodifluoromethane
with 51.2% chloropentafluoroethane; this mixed gas is designated Fluorocarbon-502
... .
Impurities:
... Dichlorofluoromethane (FC 21) ... appears as a contaminant of commercially
available FC 22.
Consumption Patterns:
CFC-22 ... IS WIDELY USED IN CENTRAL AIR-CONDITIONING SYSTEMS, PACKAGED OR
WINDOW UNITS AND HEAT PUMPS (1984)
The major use of chlorodifluoromethane is in refrigeration and air conditioning
applications which accounts for 90% of reported sales.
Annual worldwide productions (in X10+6 kg) of chlorodifluoromethane from 1970
to 1994 were as follows: 56.1 (1970); 75.0 (1975); 126.3 (1980); 153.4 (1985);
213.7 (1990).
Annual worldwide production of chlorodifluoromethane: 239.4X10+6 kg (1994)
U. S. Production:
(1984) 1.16X10+11 g (EST)
(1987) 2.74X10+8 lb
(1988) 3.32X10+8 lb
(1986) 2.74X10+8 lb
(1987) 2.84X10+8 lb
(1992) 149,526,000 kg
CHEMICAL PROFILE: Demand: 1988: 1130 million lb; 1989: 1190 million lb /Fluorocarbons/
(F-22 accounts for 30% of production)
U. S. Imports:
(1984) 5.35X10+9 g
(1986) 2.03X10+7 lb
Laboratory Methods:
Clinical Laboratory Methods:
A SIMPLE & EXTREMELY SENSITIVE HEAD-SPACE GAS-CHROMATOGRAPHIC METHOD FOR
THE ASSAY OF FLUOROCARBON PROPELLANTS, INCLUDING FREON 22, IN BLOOD IS DESCRIBED.
THE GASEOUS SAMPLE IN THE HEAD SPACE OF A SEALED CONTAINER AFTER AN EQUILIBRIUM
STATE IS REACHED IS INJECTED DIRECTLY INTO THE COLUMN. THE MINIMUM QUANTIFIABLE
CONCN FOR SOME FLUOROCARBONS WAS 6 PG/L, UP TO 5000 TIMES LOWER THAN THOSE PREVIOUSLY
REPORTED USING AN EXTERNAL METHOD FOR PREPARING SAMPLES FOR GAS CHROMATOGRAPHY
ANALYSIS. SOLUBLITIES OF 3 PROPELLANTS IN HUMAN BLOOD WERE DETERMINED.
A HEXANE EXTRACTION PROCEDURE FOR DETERMINATION OF FLUOROCARBON PROPELLANTS,
INCLUDING FREON 22, IN BLOOD & ANIMAL TISSUE BY GAS CHROMATOGRAPHY USING
ELECTRON CAPTURE DETECTION WAS EVALUATED BY A COMBINATION OF RADIOCHEMICAL AND
GAS CHROMATOGRAPHIC TECHNIQUES. THE DATA SUGGEST THAT HEXANE EXTRACTION GIVES
SIGNIFICANTLY LOW RESULTS.
A GAS CHROMATOGRAPHIC METHOD FOR THE DETERMINATION OF FLUOROCARBONS, INCLUDING
FREON 22, IN BODY FLUIDS IS DESCRIBED. THE CMPD ARE DETECTED BY A 3-H FOIL ELECTRON
CAPTURE DETECTOR. CONCN IN BODY FLUIDS ARE DETERMINED BY MEANS OF HEAD SPACE
ANALYSIS. DETECTION LIMITS FOR THE VARIOUS FLUOROCARBONS VARY BETWEEN 0.5 AND
35 PG. THE METHOD IS APPLIED IN DETERMINING FLUOROCARBON CONCN IN RAT BLOOD
IN VIVO.
Analytic Laboratory Methods:
A GAS CHROMATOGRAPHIC METHOD FOR THE DETERMINATION OF FLUOROCARBONS, INCLUDING
FREON 22, IN AIR IS DESCRIBED. THE CMPD ARE DETECTED BY A 3-H FOIL ELECTRON
CAPTURE DETECTOR. DETECTION LIMITS FOR THE VARIOUS FLUOROCARBONS VARY BETWEEN
0.5 AND 35 PG.
Several methods ... reported for the analysis of chlorodifluoromethane in
air, including ... photothermal deflection spectrophotometry. ... Detection
limit ... 1.3 ppb (4.6 ug/cu m) ...
Laser optoacoustic spectroscopy air analysis; Air analysis gas and vapor detn
in, by IR laser optoacoustic spectroscopy.
NIOSH Method 1018. Determination of Dichlorodifluoromethane by Gas Chromatography
with Flame Ionization Detection (det limit = 3 mg/cu m).
Special References:
Special Reports:
Litchfield & Longstaff; Food Chem Toxicol 22: 465-75 (1984). Comprehensive
review on the toxicology of chlorodifluoromethane.
WHO; Environmental Health Criteria 126: Partially Halogenated Chlorofluorocarbons
(Methane Derivatives) (1991).
USEPA; Chemical Hazard Information Profile: Chlorodifluoromethane (1978)
Anders MW; Environmental Health Perspectives 96: 185-191 (1991). Metabolism
and toxicity of hydrochlorofluorocarbons: Current knowledge and needs for the
future. The metabolism and toxicity of hydrochlorofluorocarbons (HCFCs), potential
replacements for ozone depleting chlorofluorocarbons, were reviewed.
Dutch expert committee for occupational standards; Directorate-General of
Labor, the Netherlands 15/87: 70 (1987). Health-based recommended occupational
exposure limits for fluorocarbons (except FC11).
Hampton J; Delic J; Cross H; Brown R; Health and Safety Executive HSE Books
V: 21 (1994). Chlorodifluoromethane. Criteria document for an occupational exposure
limit.
Longstaff E; Annals of the New York Academy of Sciences 534: 283-298 (1988). Carcinogenic and mutagenic potential of several fluorocarbons. A series of chlorofluorocarbons (CFC) was evaluated for carcinogenic potential in two comprehensive toxicity studies.
Synonyms and Identifiers:
Synonyms:
F 22
**PEER REVIEWED**
R 22
**PEER REVIEWED**
ALGEON 22
**PEER REVIEWED**
ALGOFRENE TYPE 6
**PEER REVIEWED**
ARCTON 4
**PEER REVIEWED**
Chlorofluorocarbon 22
**PEER REVIEWED**
Daiflon 22
**PEER REVIEWED**
DIFLUOROCHLOROMETHANE
**PEER REVIEWED**
Difluoromonochloromethane
**PEER REVIEWED**
Dymel 22
**PEER REVIEWED**
ELECTRO-CF 22
**PEER REVIEWED**
ESKIMON 22
**PEER REVIEWED**
FC 22
**PEER REVIEWED**
FLUOROCARBON-22
**PEER REVIEWED**
Forane 22 B
**PEER REVIEWED**
FREON 22
**PEER REVIEWED**
FRIGEN
**PEER REVIEWED**
FRIGEN 22
**PEER REVIEWED**
GENETRON 22
**PEER REVIEWED**
Haltron 22
**PEER REVIEWED**
Hydrochlorofluorocarbon 22
**PEER REVIEWED**
ISCEON 22
**PEER REVIEWED**
ISOTRON 22
**PEER REVIEWED**
Khladon 22
**PEER REVIEWED**
Methane, chlorodifluoro-
**PEER REVIEWED**
MONOCHLORODIFLUOROMETHANE
**PEER REVIEWED**
PROPELLANT 22
**PEER REVIEWED**
REFRIGERANT 22
**PEER REVIEWED**
UCON 22
**PEER REVIEWED**
Formulations/Preparations:
USEPA/OPP Pesticide Code 000015; Trade Names: Freon 22. /Former trade names/
Grade: technical; 99.9% pure
It is available as a liquified gas in an azeotropic mixture of 48.8% chlorodifluoromethane
with 51.2% chloropentafluoroethane; this mixed gas is designated Fluorocarbon-502
... .
Shipping Name/ Number DOT/UN/NA/IMO:
UN 1018; Chlorodifluoromethane
IMO 2.2; Chlorodifluoromethane
Standard Transportation Number:
49 045 52; Chlorodifluoromethane (R-22)
RTECS Number:
NIOSH/PA6390000
Administrative Information:
Hazardous Substances Databank Number: 143
Last Revision Date: 20010809
Last Review Date: Reviewed by SRP on 1/20/2001
Update History:
Complete Update on 08/09/2001, 1 field added/edited/deleted.
Complete Update on 05/23/2001, 64 fields added/edited/deleted.
Field Update on 05/16/2001, 1 field added/edited/deleted.
Field Update on 02/09/2001, 2 fields added/edited/deleted.
Complete Update on 06/12/2000, 1 field added/edited/deleted.
Complete Update on 03/28/2000, 1 field added/edited/deleted.
Complete Update on 02/02/2000, 1 field added/edited/deleted.
Complete Update on 09/21/1999, 1 field added/edited/deleted.
Complete Update on 08/26/1999, 1 field added/edited/deleted.
Complete Update on 07/20/1999, 5 fields added/edited/deleted.
Complete Update on 11/12/1998, 1 field added/edited/deleted.
Complete Update on 06/02/1998, 1 field added/edited/deleted.
Complete Update on 10/17/1997, 1 field added/edited/deleted.
Complete Update on 03/27/1997, 2 fields added/edited/deleted.
Complete Update on 02/05/1997, 1 field added/edited/deleted.
Complete Update on 01/09/1997, 1 field added/edited/deleted.
Complete Update on 07/22/1996, 5 fields added/edited/deleted.
Complete Update on 05/03/1996, 1 field added/edited/deleted.
Complete Update on 03/12/1996
Complete Update on 01/18/1996, 1 field added/edited/deleted.
Complete Update on 11/10/1995, 1 field added/edited/deleted.
Complete Update on 06/07/1995, 49 fields added/edited/deleted.
Field Update on 05/26/1995, 1 field added/edited/deleted.
Field Update on 01/18/1995, 1 field added/edited/deleted.
Field Update on 12/19/1994, 1 field added/edited/deleted.
Complete Update on 07/20/1994, 1 field added/edited/deleted.
Complete Update on 05/05/1994, 1 field added/edited/deleted.
Complete Update on 03/25/1994, 1 field added/edited/deleted.
Complete Update on 01/25/1994, 1 field added/edited/deleted.
Complete Update on 08/07/1993, 1 field added/edited/deleted.
Complete Update on 08/04/1993, 1 field added/edited/deleted.
Complete Update on 02/05/1993, 1 field added/edited/deleted.
Field update on 12/11/1992, 1 field added/edited/deleted.
Complete Update on 01/23/1992, 1 field added/edited/deleted.
Complete Update on 02/13/1991, 84 fields added/edited/deleted.
Field Update on 01/15/1990, 1 field added/edited/deleted.
Complete Update on 01/11/1990, 79 fields added/edited/deleted.
Field Update on 11/09/1988, 1 field added/edited/deleted.
Complete Update on 10/03/1986