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Reports
ACTIVITY: Insecticide,
Fungicide, Propellant, EPA List 2 Inert (Halogenated organic)
Structure:
Adverse Effects:
Body Weight Decrease
Brain
Cancer: limited evidence, fibrosarcomas
Cholesterol
CNS
Endocrine: Adrenal
Endocrine: Pituitary
Eye - Microphthalmia
and Anophthalmia
Heart
Kidney
Liver
Lung
Mutagenic (Eye)
Salivary Glands
Spinal Cord
Tremors
Environmental
Chlorodifluoromethane
is produced extensively for use in refrigeration and air
conditioning; significant quantities are subsequently released
into the atmosphere, resulting in widespread, low-level
human exposure. Occupational exposure to chlorodifluoromethane
occurs during its production and use.
Ref:
IARC 1986.
http://www.fluorideaction.org/pesticides/chlorodifluoromethane.iarc.htm
|
Animal
Data - INHALATION: 4 hour, LC50, rat: 220,000 ppm.
The
compound is a skin irritant and a slight eye irritant, but
is not a skin sensitizer in animals. Effects from single
high exposures include central nervous
system depression, anesthesia, rapid breathing, lung congestion
and microscopic liver changes. Cardiac sensitization
occurred in dogs at 50,000 ppm or greater from the action
of exogenous epinephrine... Long-term
exposures to 50,000 ppm (v/v) of vapors produced organ
weight increases and a decrease in body weight gain...
In chronic inhalation studies, "FREON" 22, at a concentration
o 50,000 ppm (v/v), produced a small, but statistically
significant increase of late-occurring
tumors involving salivary glands in male rats, but
not female rats or male or female mice...
"FREON"
22 was mutagenic in some strains of
bacteria in bacterial cell cultures, but not mammalian
cell cultures or animals. It did not cause heritable genetic
damage in mammals.
A
slight, but significant increase in developmental toxicity
was observed at high concentrations (50,000
ppm) of "FREON" 22, a concentration which also produced
toxic effects in the adult animal. Based on these findings,
and other negative developmental studies, "FREON" 22 is
not considered a unique hazard to the conceptus. Studies
of the effects of "FREON" 22 on male reproductive performance
have been negative. Specific studies
to evaluate the effect on female reproductive performance
have not been conducted...
Ref:
Material Safety
Data Sheet for Freon 22. DuPont.
1996.
|
Body
Weight Decrease (click
on for all fluorinated pesticides)
Long-term
exposures to 50,000 ppm (v/v) of vapors produced organ weight
increases and a decrease in body weight
gain...
Ref: Material Safety Data Sheet for
Freon 22. DuPont. 1996.
http://www.fluoridealert.org/pesticides/chlorodifluoromethane.msds.pdf
The
Registry of Toxic Effects of Chemical Substances
Methane, chlorodifluoro - RTECS
#: PA6390000
NIOSH - National Institute for Occupational Safety and Health |
ROUTE/
ORGANISM |
DOSE
|
EFFECT |
REFERENCE
|
oral
rat |
lowest
published toxic dose: 2,457 mg/kg/26 week- intermittent |
Brain
and Coverings: Other degenerative changes
Blood:
Changes in other cell count (unspecified)
Nutritional
and Gross Metabolic: Weight loss or decreased weight gain
|
Gigiena
i Sanitariya. For English translation, see HYSAAV. (V/O Mezhdunarodnaya
Kniga, 113095 Moscow, USSR). V 48(8): 69,1983. |
Brain
(click
on for all fluorinated pesticides)
The
Registry of Toxic Effects of Chemical Substances
Methane, chlorodifluoro - RTECS
#: PA6390000
NIOSH - National Institute for Occupational Safety and Health |
ROUTE/
ORGANISM |
DOSE
|
EFFECT |
REFERENCE
|
inhalation
mouse |
lowest
published toxic concentration: 50 gm/m3/6 hour/43 week- intermittent
|
Brain
and Coverings: Other degenerative changes
Spinal Cord: Other degenerative changes
Behavioral: Alteration of classical conditioning |
Trudy
Leningradskogo Sanitarno-Gigienicheskogo Meditsinskogo Instituta.
(Leningrad, Russia).
V 75: 231,1963. |
oral
rat |
lowest
published toxic dose: 2,457 mg/kg/26 week- intermittent |
Brain
and Coverings: Other degenerative changes
Blood:
Changes in other cell count (unspecified)
Nutritional
and Gross Metabolic: Weight loss or decreased weight gain
|
Gigiena
i Sanitariya. For English translation, see HYSAAV. (V/O Mezhdunarodnaya
Kniga, 113095 Moscow, USSR). V 48(8): 69,1983. |
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.
Ref: Fitzgerald RL et al; J Forensic Sci
38 (2): 477-483 (1993); cited in the TOXNET profile from the Hazardous
Substances Data Bank.
http://www.fluoridealert.org/pesticides/chlorodifluoromethan.toxnet.htm
Cancer
(click
on for all fluorinated pesticides)
Experimental data.
Chlorodifluoromethane was tested for carcinogenicity
in one experiment in rats by oral administration by gavage
and in experiments in rats and mice by inhalation exposure. No
increase in tumour incidence was observed in rats after oral administration.
The inhalation study in mice was inconclusive for males, and negative
results were obtained for females. In the
inhalation study in rats, males receiving the high dose had increased
incidences of fibrosarcomas and Zymbal-gland tumours; negative
results were obtained for female rats...
Evaluation: There
is limited evidence for the carcinogenicity of chlorodifluoromethane
to experimental animals.
Ref: 5. Summary of Data Reported and Evaluation.
International Agency for Research on Cancer IARC. 1986
http://www.fluorideaction.org/pesticides/chlorodifluoromethane.iarc.htm
Cholesterol
(click
on for all fluorinated pesticides)
Lee and Suzuki (1981)
exposed groups of 16 male Sprague-Dawley rats to 0 or 50,000 ppm
HCFC-22 for 5 hours/day, 7 days/week for 8 weeks (duration- adjusted
concentrations = 0 or 36,800 mg/cu.m, respectively). Six rats/group
were sacrificed at 8 weeks, and the rest were used in a fertility
study (discussed below). The only exposure-related effects noted
were a slight decrease in prostate weight (without accompanying
histopathological changes), an increase
in plasma cholesterol,
and decreases in plasma glucose and triglycerides. The toxicological
significance of these changes is not clear because functional
studies on adrenal or hepatic function were not undertaken, and
there were no histopathological changes in these organs. Nevertheless,
a LOEL of 50,000 ppm [LOEL(HEC) = 36,800 mg/cu.m] can be estimated
from this study.
Ref: US EPA IRIS (Integrated Risk Information
System).
http://www.fluoridealert.org/pesticides/chlorodifluoromethane.iris.htm
CNS
(click
on for all fluorinated pesticides)
The substance may cause
effects on the cardiovascular system
and central nervous system, resulting
in cardiac disorders and central
nervous system depression.
Ref: ICSC: 0049. March 2002. International
Programme on Chemical Safety (IPCS).
http://www.inchem.org/documents/icsc/icsc/eics0049.htm
Potential Health Effects
- Inhalation of high concentrations of vapor is harmful and may
cause heart irregularities, unconsciousness or death. .. Human
Health Effects: Higher exposures may lead to temporary alteration
of the heart's electrical activity with irregular pulse, palpitations,
or inadequate circulation. Fatality may occur from gross overexposure.
Individuals with preexisting diseases of
the central nervous or cardiovascular system may have increased
susceptibility to the toxicity of excessive exposures.
Animal
Data - INHALATION: 4 hour, LC50, rat: 220,000 ppm. The
compound is a skin irritant and a slight eye irritant, but is
not a skin sensitizer in animals. Effects from single high exposures
include central nervous
system depression, anesthesia, rapid breathing, lung congestion
and microscopic
liver changes...
Ref: Material Safety Data Sheet for Freon
22. DuPont. 1996.
http://www.fluoridealert.org/pesticides/chlorodifluoromethane.msds.pdf.
Endocrine:
Adrenal
and
Pituitary
(click
on for all fluorinated pesticides)
Increased kidney, adrenal
and pituitary weights... The female
rats in the 50,000-ppm group exhibited a statistically significant
increase in liver (absolute and relative), kidney (absolute),
adrenal (absolute), and pituitary
(absolute, at interim sacrifice--pituitaries
were not weighed at terminal sacrifice) weights. No nonneoplastic
histopathological changes attributable to exposure to HCFC-22
were observed. The liver weight effect was not considered adverse
because it did not exceed a 10% weight change and there was no
histopathology observed. Based on effects on kidney, adrenal,
and pituitary weight, a NOAEL of
10,000 ppm [NOAEL(HEC) = 5260 mg/cu.m] and a LOAEL of 50,000 ppm
[LOAEL(HEC) = 26,300 mg/cu.m] can be estimated.
Ref: US EPA IRIS for Chlorodifluoromethane.
http://www.fluoridealert.org/pesticides/chlorodifluoromethane.iris.htm
Eye
- Microphthalmia
and Anophthalmia (click
on for all fluorinated pesticides)
Chlorodifluoromethane
(FC-22) was evaluated for embyotoxicity and teratogenicity in
groups of 40 pregnant Charles River rats exposed to the test substance
by inhalation at concentrations of 0, 0.05, 0.10, and 2.00% on
days 6-15 of gestation. No clinical signs of toxicity were observed
in maternal animals. The number of implantations, early and late
resorptions, and number of live fetuses per litter were unaffected.
There was a sporadic appearance of major
malformations of the eye in all test groups. The increased
incidence of eye defects was not statistically significant. Authors
believe that the test substance may have interacted with the genetic
make-up of affected fetuses and caused the increased expressivity
of a mutant gene. The authors considered
the test substance to be a mutagen under the conditions of this
study.
Ref: 1992 - INITIAL SUBMISSION: EMBRYOTOXIC
AND TERATOGENIC STUDIES IN RATS WITH INHALED CHLORODIFLUOROMETHANE
WITH COVER LETTER DATED 06-15-92 AND ATTACHMENTS. HASKELL LABORATORY.
Report Nos. NTIS/OTS0540606 and EPA/OTS; Doc #88-920004258.
Chlorodifluoromethane
causes malformations of the eyes of fetal rats,
but has no reproductive effect in male rats and does not cause
prenatal toxicity in rabbits following exposure by inhalation.
Ref: 5. Summary of Data Reported and Evaluation.
International Agency for Research on Cancer IARC. 1986
http://www.fluorideaction.org/pesticides/chlorodifluoromethane.iarc.htm
Palmer et al. (1978a)
conducted a large developmental study in an attempt to elucidate
the role of CFC-22 exposure in the eye lesion seen in the previous
studies (see Culik et al., 1977, and Culik and Crowe, 1978,
in the Additional Studies/Comments section). In this study,
an experimental design was used in which 34 control pregnant
rats were used, and 22/group were exposed to 100, 1000, or 50,000
ppm of CFC-22 (354, 3,540, or 176,800 mg/cu.m, respectively)
for 6 hours/day on gestation days 6-15. This protocol was repeated
19 times so that more than 6000 control fetuses and 4000 fetuses
from each exposed group were thoroughly examined for the eye
defect... The eye abnormalities (small
or missing eye) were noted again in
all exposure groups, but statistical significance for
these effects was achieved only in the 50,000-ppm group. The
combined incidences of microphthalmia
and anophthalmia were 3/607, 5/393, 3/390, and 10/383
in the control, 100, 1000, and 50,000-ppm groups, respectively.
Additional data on the control incidence of the eye effects
during 10 years after the Palmer et al. (1978a) study was conducted
are presented in European Chemical Industry Ecology and Toxicology
Center (ECETOC) (1989). The data were analyzed in blocks of
19 studies, and the control incidence in the first six blocks
was similar to the controls in the Palmer study, while in later
studies, the control incidence increased (0.4-2.4% in the last
four blocks) and, in one experiment, was similar to the incidence
found in the high-dose group in the Palmer study (2.6%). The
incidence of the eye abnormality in the high-concentration group
in the Palmer et al. (1978a) study is significantly increased
compared with the overall controls in the studies conducted
in the 10-year period after the study (ECETOC, 1989), adding
strength to the interpretation that this is an adverse, treatment-related
effect. This study identifies a LOAEL for maternal weight,
fetal weight, and fetal abnormalities at 50,000 ppm. The LOAEL(HEC)
is 176,800 mg/cu.m for the fetal effects (no duration adjustment
is applied) and 44,200 mg/cu.m for the maternal toxicity (exposure
is adjusted for duration).
Ref: US EPA IRIS for Chlorodifluoromethane.
http://www.fluoridealert.org/pesticides/chlorodifluoromethane.iris.htm
Teratogenicity
was evaluated in 4 groups of 19 pregnant CD female rats receiving
Arcton 22 via inhalation at concentration levels of 0, 100,
1,000 and 50,000 ppm for 6 hours per day on gestation days 6
through 15. There were no treatment-related effects in appearance,
behavior, mortality, or pregnancy rate. At 50,000 ppm maternal
weight gain was slightly lower than the control. There were
no effects on body weight at 100 or 1,000 ppm. In all test groups
litter size, post-implantation loss, litter wight, and mean
fetal weight were similar to the control. At
50,000, there was an increased incidence of anophthalmic•
fetuses.
Ref: 1989 - EFFECT
OF ACRTON 22 ON PREGNANT RATS: RELATIONSHIP TO ANOPHTHALMIA
AND MICROPHTHALMIA WITH ATTACHMENTS AND COVER LETTER DATED 07-05-89.
Report Nos. NTIS/OTS0520413 and EPA/OTS; Doc #87-890000011
•
Anophthalmic
definition:
Absence of an eye(s). It can be a congenital (born without)
or an acquired condition (surgically removed).
Heart
(click on for all fluorinated
pesticides)
The substance may cause
effects on the cardiovascular system
and central nervous system, resulting in cardiac
disorders and central nervous system depression.
Ref: ICSC: 0049. March 2002. International
Programme on Chemical Safety (IPCS).
http://www.inchem.org/documents/icsc/icsc/eics0049.htm
Potential Health Effects
- Inhalation of high concentrations of vapor is harmful and may
cause heart irregularities, unconsciousness or death. ..
Human Health Effects: Higher exposures may lead to temporary
alteration of the heart's electrical activity with irregular pulse,
palpitations, or inadequate circulation. Fatality may occur
from gross overexposure. Individuals with
preexisting diseases of the central nervous or cardiovascular
system may have increased susceptibility to the toxicity of excessive
exposures.
Ref: Material Safety Data Sheet for Freon
22. DuPont. 1996.
http://www.fluoridealert.org/pesticides/Chlorodifluoromethane.MSDS.pdf
PubMed abstract: Case
report of a plumber's fatal work accident. Investigations on the
causes of death made at post mortem showed that the worker had
absorbed a large quantity of freon 22
(chlorodifluoromethane) which is known to
be a narcotic agent and capable of
inducing cardiac arrhythmia. It is believed freon inhalation
was the cause of loss of consciousness with consequent death from
drowning in the water issuing from the pipes. It is concluded
that preventive measures need to be reinforced by adequate information
to the workforce on the risks connected to this type of gas.
Ref: Med Lav 1992 Jul-Aug;83(4):361-4. [Sudden
death caused by freon 22?]. [Article in Italian]; by M Dal
Grande et al.
PubMed Abstract: After
exposure to decomposed chlorodifluoromethane (freon-22), a 65-year-old
man developed respiratory symptoms such
as cough, blood-stained sputum, and increasing dyspnea. Three
weeks later, his family doctor diagnosed infectious bronchitis.
Another week later he died due to myocardial
infarction. The discussion focuses on an inflammatory process
caused by the inhalation of decomposed freon and its possible
association with myocardial infarction.
Ref: Scand J Work Environ Health 2002 Jun;28(3):205-7,
Inhalation
of decomposed chlorodifluoromethane (freon-22) and myocardial
infarction; by Sjogren
B, Gunnare S, Sandler H.
Kidney
(click
on for all fluorinated pesticides)
Increased
kidney, adrenal and pituitary weights...
The female rats in the 50,000-ppm group exhibited a statistically
significant increase in liver (absolute and relative), kidney
(absolute), adrenal (absolute), and pituitary (absolute, at interim
sacrifice--pituitaries were not weighed at terminal sacrifice)
weights. No nonneoplastic histopathological changes attributable
to exposure to HCFC-22 were observed. The liver weight effect
was not considered adverse because it did not exceed a 10% weight
change and there was no histopathology observed. Based on effects
on kidney, adrenal, and pituitary
weight, a NOAEL
of 10,000 ppm [NOAEL(HEC) = 5260 mg/cu.m] and a LOAEL of 50,000
ppm [LOAEL(HEC) = 26,300 mg/cu.m] can be estimated.
Ref: US EPA IRIS for Chlorodifluoromethane.
http://www.fluoridealert.org/pesticides/chlorodifluoromethane.iris.htm
Liver
(click
on for all fluorinated pesticides)
Animal
Data - INHALATION: 4 hour, LC50, rat: 220,000 ppm. The
compound is a skin irritant and a slight eye irritant, but is
not a skin sensitizer in animals. Effects from single high exposures
include central nervous system depression,
anesthesia, rapid breathing, lung congestion and
microscopic liver changes...
Ref:
Material Safety Data
Sheet for Freon 22. DuPont. 1996.
Lung
(click
on for all fluorinated pesticides)
Animal
Data - INHALATION: 4 hour, LC50, rat: 220,000 ppm. The
compound is a skin irritant and a slight eye irritant, but is
not a skin sensitizer in animals. Effects from single high exposures
include central nervous system depression,
anesthesia, rapid breathing, lung congestion
and microscopic liver changes...
Ref:
Material Safety Data
Sheet for Freon 22. DuPont. 1996.
Mutagenic
(click
on for all fluorinated pesticides)
Chlorodifluoromethane
(FC-22) was evaluated for embyotoxicity and teratogenicity in
groups of 40 pregnant Charles River rats exposed to the test substance
by inhalation at concentrations of 0, 0.05, 0.10, and 2.00% on
days 6-15 of gestation. No clinical signs of toxicity were observed
in maternal animals. The number of implantations, early and late
resorptions, and number of live fetuses per litter were unaffected.
There was a sporadic appearance of major
malformations of the eye in all test groups. The increased
incidence of eye defects was not statistically significant. Authors
believe that the test substance may have interacted with the genetic
make-up of affected fetuses and caused the increased expressivity
of a mutant gene. The authors considered
the test substance to be a mutagen under the conditions of this
study.
Ref: 1992 - INITIAL SUBMISSION: EMBRYOTOXIC
AND TERATOGENIC STUDIES IN RATS WITH INHALED CHLORODIFLUOROMETHANE
WITH COVER LETTER DATED 06-15-92 AND ATTACHMENTS. HASKELL LABORATORY.
Report Nos. NTIS/OTS0540606 and EPA/OTS; Doc #88-920004258.
Teratogenicity
was evaluated in 4 groups of 19 pregnant CD female rats receiving
Arcton 22 via inhalation at concentration levels of 0, 100,
1,000 and 50,000 ppm for 6 hours per day on gestation days 6
through 15. There were no treatment-related effects in appearance,
behavior, mortality, or pregnancy rate. At 50,000 ppm maternal
weight gain was slightly lower than the control. There were
no effects on body weight at 100 or 1,000 ppm. In all test groups
litter size, post-implantation loss, litter wight, and mean
fetal weight were similar to the control. At
50,000, there was an increased incidence of anophthalmic•
fetuses.
Ref: 1989 - EFFECT
OF ACRTON 22 ON PREGNANT RATS: RELATIONSHIP TO ANOPHTHALMIA
AND MICROPHTHALMIA WITH ATTACHMENTS AND COVER LETTER DATED 07-05-89.
Report Nos. NTIS/OTS0520413 and EPA/OTS; Doc #87-890000011
•
Anophthalmic
definition:
Absence of an eye(s). It can be a congenital (born without)
or an acquired condition (surgically removed).
Salivary
Glands (click
on for all fluorinated pesticides)
-- 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. [IARC. Monographs on the Evaluation of the
Carcinogenic Risk of Chemicals to Man. Geneva: World Health Organization,
International Agency for Research on Cancer,1972-PRESENT. (Multivolume
work).,p. V41 242 (1986)]
-- 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. [ICI Americas, Inc.; Chlorofluorocarbon
22 (CFC 22 - chlorodifluoromethane). (1981), EPA Document No.
FYI-OTS-0481-0111, Fiche No. 0111-0 ]
Ref: TOXNET profile from Hazardous Substances
Data Base for Chlorodifluoromethane.
http://www.fluoridealert.org/pesticides/chlorodifluoromethan.toxnet.htm
Spinal
Cord (click
on for all fluorinated pesticides)
mouse lowest published toxic concentration: 50 gm/m3/6 hour/43
week- intermittent Brain and Coverings: Other
degenerative changes: Spinal Cord. Other degenerative changes.
Behavioral: Alteration of classical conditioning. [Trudy Leningradskogo
Sanitarno-Gigienicheskogo Meditsinskogo Instituta. (Leningrad,
Russia) 75,231,1963]
Ref: NIOSH. Registry of Toxic Effects. July
2000.
http://www.fluoridealert.org/pesticides/chlorodifluoromethane.niosh.htm#TLSMA6
Tremors
(click
on for all fluorinated pesticides)
... 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. [Patty, F. (ed.). Industrial Hygiene and Toxicology:
Volume II: Toxicology. 2nd ed. New York: Interscience Publishers,
1963. 1324]
Ref: TOXNET profile from Hazardous Substances
Data Base for CHLORODIFLUOROMETHANE
http://www.fluoridealert.org/pesticides/chlorodifluoromethan.toxnet.htm
Environmental
(click on for all fluorinated pesticides)
"Dangerous
for the ozone layer"
Ref:
OBSERVATION LIST: examples of substances requiring particular
attention second, revised edition, 1998. Issued by the Swedish
National Chemicals Inspectorate in collaboration with the
Swedish Environmental Protection Agency and the Swedish
National Board of Occupational Safety and Health.
http://www.fluorideaction.org/pesticides/sweden.dangerous.subs.1998.pdf
Abstract:
Chlorodifluoromethane
(HCFC-22), the most widely used substitute
for chlorofluorocarbons, is currently emitted into the atmosphere
at a global rate of about 220,000 tyr-1. In this
work, national emissions of HCFC-22 for the year 1990 are
estimated using the calculated emissions of CFC-12 as a
surrogate distribution function. The releases so calculated
match the sp arse published data in most cases.
Ref:
Estimated national releases to the atmosphere of chlorodifluoromethane
(HCFC-22) during 1990; by Pauline M. Midgley and Archie
McCulloch. Atmospheric Environment ; Volume 31, Issue 6
, March 1997, Pages 809-811.
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