Adverse Effects
Dichlorodifluoromethane (Freon 12)
CAS No. 75-71-8

 
 

Return to Dichlorodifluoromethane Index Page

ACTIVITY: Insecticide, Fungicide Propellant, EPA List 2 Inert (halogenated organic)
Structure:

Adverse Effects:
Ataxia
Brain
CNS
Heart
Leukemia
Liver
Lung
Tremors/Convulsions
Environmenta
l

As of September 27, 2003, Dichlorodifluoromethane is listed by US EPA as a List 2 Inert in pesticidal formulations. See: http://www.epa.gov/opprd001/inerts/inerts_list2.pdf


Accidental death of child playing with deodorant aerosol
Source: Lancet; VOL 1 ISS Apr 8 1978
Author: Jefferson IG
Author Address: Westminister Children's Hosp., London SW1, England Comments: Letters Abstract: IPA COPYRIGHT: ASHP A 4-yr-old boy, playing with an antiperspirant deodorant in the bathtub, inhaled the propellants, 50.5% trichloromonofluoromethane (fluorocarbon 11) and 43% dichlorodifluoromethane (fluorocarbon 12), became deeply unconscious with no spontaneous respiration, and no cerebral activity, and died 5 days later.

Body Burden: In a pilot study of pollutants in the milk of women living in 4 urban-industrial areas in the US, dichlorodifluoromethane was identified, not quantified, in 2 of 8 samples(1). [(1) Pellizzari ED et al; Bull Environ Contam Toxicol 28: 322-8 (1982)]

Manufacturing/Use Information: Major Uses:

The active ingredient is no longer contained in any registered pesticide products ... "cancelled." [United States Environmental Protection Agency/ Prevention, Pesticides and Toxic Substances; Status of Pesticides in Registration, Reregistration, and Special Review. (1998) EPA 738-R-98-002 312] - Note from FAN: An "Inert" used in a pesticidal formulation is not considered an "active ingredient."

Fully halogenated chlorofluorocarbons (CFCs) such as dichlorodifluoromethane were scheduled for production phase-out in 1987 by the Montreal Protocol. Although originally scheduled for 50% production phase-out by the year 2000 in developed countries, the worsening ozone depletion has forced acceleration of the CFC phase-out.

Leak-detecting agent; freezing of foods by direct contact; /SRP: former use/ chilling of cocktail glasses, refrigerant in air conditioners, plastics, blowing agent, solvent

To prepare frozen tissue sections /former use/

In various "skin freezes" by aerosol application, as propellant for antibiotic powders, mastitis formulations, etc, and for admixture to other gases such as ethylene oxide to make them non-flammable. /former use/

Manufacturers:
Allied Signal Inc. - Prod site: Danville, IL 61834
Dupont Chemical Inc. - Prod sites: Antioch, CA 94509; Montague, MI 49437.
Elf Atochem North America Inc. - Prod site: Calvert City, KT 42029.

Dichlorodifluoromethane concn in room air as a result of release of aerosol can products. Level at periods after 60 sec release of hair spray in a 29.3 cu m room (in mg/cu m): during release: 306.8; 30 min after: 12.4; 60 min after: 0.5. Level at periods after 30 second release of insect spray in a 21.4 cu m room (in mg/cu m): 1 min: 2,304.0; 60 min: 130.4; 150 min: 56.8. /From table/ [USEPA; Ambient Water Quality Criteria Doc: Halomethanes p.C-19 (1980) EPA 440/5-80-051]

Ref: Dichlorodifluoromethane. TOXNET profile from Hazardous Substances Data Bank. http://www.fluorideaction.org/pesticides/dichlorodifluorometh.toxnet.htm


Freon 12. Standards for Inhalation Exposure A. Occupational Exposure Limits (NIOSH, 1997; ACGIH, 1994).

1. Ceiling Limit (C) (not to be exceeded at any time):

Not established.

2. Short-Term Exposure Limit (STEL or ST):

Not established.

3. 8-Hour Time Weighted Average (TWA):

1,000 ppm (4,950 mg/m 3 )

4. 10-Hour Time Weighted Average (TWA):

1,000 ppm (4,950 mg/m 3 )

5. Immediately Dangerous to Life & Health (IDLH):

15,000 ppm (74,250 mg/m 3 )

Freon 12. Acute Reference Exposure Levels (1-hour exposure) (OEHHA, 1999)

1. Level protective against mild adverse effects:

Not established

2. Level protective against severe adverse effects:

Not established

3. Level protective against mild adverse effects:

Not established

Freon 12. Chronic Reference Exposure Level (multiple years) (OEHHA, 2002A)

Level protective of adverse health effects:

Not established.

Freon 12. Chronic Reference Concentration (lifetime exposure) (IRIS, 2003)

Level protective of adverse health effects:

Not established.

Freon 12. Preliminary Remediation Goals (U.S. EPA, 2002, Region IX):

for Residential Soil

94 mg/kg

for Tap Water

390 ppb (0.4 mg/l)

for Ambient Air

0.21 mg/m 3

Ref: September 24, 2003 (Revised). Released November 7, 2003) - FREON [11, 12, 113]. Technical Support Document: Toxicology. Clandestine Drug Labs/ Methamphetamine. Volume 1, Number 11. California EPA, Office of Environmental Health Hazard Assessment (OEHHA), Department of Toxic Substances Control.

Ataxia (click on for all fluorinated pesticides)

DOGS, MONKEYS, & GUINEA PIGS EXPOSED TO 20% OF GAS IN AIR FOR SEVERAL HR A DAY FOR SEVERAL DAYS SHOWED TEMPORARY INTOXICATION WITH TREMORS, ATAXIA, AND TENDENCY TO STARE, SALIVATE, & LACRIMATE, BUT NO CUMULATIVE TOXIC EFFECT & NO SPECIFIC OCULAR DISTURBANCE. [Grant, W.M. Toxicology of the Eye. 3rd ed. Springfield, IL: Charles C. Thomas Publisher, 1986. 322]
Ref: Profile from Hazardous Substances Data Bank for Dichlorodifluoromethane.
http://www.fluoridealert.org/pesticides/Dichlorodifluorometh.TOXNET.htm

Brain (click on for all fluorinated pesticides)

Chronic effects ... In the occupational setting, chronic fluorocarbon exposure has been associated with a syndrome of impaired psychomotor speed, impaired memory and learning, and emotional instability (Reprotext, 2003). Repeated or prolonged skin contact may cause dermatitis (NIOSH, 2001E; NIOSH, 2001D).
Ref: September 24, 2003 (Revised) - FREON [11, 12, 113]. Technical Support Document: Toxicology. Clandestine Drug Labs/ Methamphetamine. Volume 1, Number 11. California EPA, Office of Environmental Health Hazard Assessment (OEHHA), Department of Toxic Substances Control.

There is a significant accumulation of fluorocarbons in brain, liver and lung compared to blood levels, signifying a tissue distribution of fluorocarbons similar to that of chloroform. /Fluorocarbons/ [Clayton, G.D., F.E. Clayton (eds.) Patty's Industrial Hygiene and Toxicology. Volumes 2A, 2B, 2C, 2D, 2E, 2F: Toxicology. 4th ed. New York, NY: John Wiley & Sons Inc., 1993-1994. 1203]
Ref: Profile from Hazardous Substances Data Bank for Dichlorodifluoromethane.
http://www.fluoridealert.org/pesticides/Dichlorodifluorometh.TOXNET.htm

CNS (click on for all fluorinated pesticides)

-- Health Hazards - General. ...At high concentrations, Freon vapor may cause pulmonary edema and neurological problems such as central nervous system depression, dizziness, headache, drowsiness, tremors, seizures, confusion, in-coordination, loss of consciousness, and paralysis (Hazardtext, 2003B; Dupont, 1996A; OSHA, 1998; NIOSH, 2003C).
-- Predisposing Conditions. Individuals with pre-existing diseases of the central nervous or cardiovascular system may have increased susceptibility to the effects of Freons (Dupont, 1996A; OSHA, 1998; Dupont, 1996B; Dupont, 1996D). Persons exposed to epinephrine or other sympathomimetic amines, e.g., bronchodilators and nasal decongestants (e.g., Sudafed •), might be at increased risk for the cardiotoxic effects of Freons (Reprotext, 2003).
-- Special Concerns for Children. Children may inhale relatively larger doses of Freon because, relative to their body weight, they have a greater lung surface area and larger minute volume than adults. Since Freon has a high vapor density, children could also receive high doses due to their short stature and the higher levels of Freon vapor that may be present near the ground when Freon is spilled.

Ref: September 24, 2003 (Revised) - FREON [11, 12, 113]. Technical Support Document: Toxicology. Clandestine Drug Labs/ Methamphetamine. Volume 1, Number 11. California EPA, Office of Environmental Health Hazard Assessment (OEHHA), Department of Toxic Substances Control.

Heart (click on for all fluorinated pesticides)

-- 11 subjects (7 being maintenance technicians of large cooling and refrigerating systems) were exposed for 130 min to CFC-12 (weighted exposure 0.46, 49.9, and 87.7 g/cu m. ... This led to acute reduction of ventilatory lung capacity only at the two highest CFC-12 concentrations, under which conditions a significant decrease in the heart frequency was also observed. [WHO; Environmental Health Criteria 113: Fully Halogenated Chlorofluorocarbons p.90 (1990)]
-- Ten subjects /were exposed/ to CFC-11, CFC-12, CFC-114, two mixtures of CFC-11 and CFC-12, and a mixture of CFC-12 and CFC-114 (breathing concentrations between 16 and 150 g/cu m) for 15, 45, or 60 seconds, and found significant acute reduction of ventilatory lung capacity (FEV50, FEF25) on exposure to each chlorofluorocarbon, as well as bradycardia and increased variability in heart rate in seven subjects, negative T-waves in two subjects (one was exposed to CFC-11 and CFC-12), and atrioventricular block in 1 subject (CFC-114). Mixtures exerted stronger respiratory effects than individual chlorofluorocarbon at the
same level of exposure. [WHO; Environmental Health Criteria 113: Fully Halogenated Chlorofluorocarbons p.90 (1990)]
-- Deaths resulting from cardiovascular collapse after arrhythmias have been reported after inhalation of Freons 11 and 12. [Ellenhorn, M.J. and D.G. Barceloux. Medical Toxicology - Diagnosis and Treatment of Human Poisoning. New York, NY: Elsevier Science Publishing Co., Inc. 1988. 528]
Ref: Profile from Hazardous Substances Data Bank for Dichlorodifluoromethane.
http://www.fluoridealert.org/pesticides/Dichlorodifluorometh.TOXNET.htm

-- Health Hazards - General ... Inhalation of high concentrations may also result in temporary alteration of the heart’s electrical activity by increasing the sensitivity of the heart to the arrhythmogenic action of epinephrine, causing irregular pulse, palpitations, or inadequate circulation (Dupont, 1996A; Dupont, 1996F; OSHA, 1998; Reprotext, 2003). Deliberate inhalation (“sniffing”) may cause death without warning (Dupont, 1996A; Dupont, 1996F; OSHA, 1998).
-- Acute Effects ... Inhalation of high concentrations (~5,000 ppm) is associated with the development of arrhythmias and sudden death due to myocardial sensitization to endogenous catecholamines (e.g., epinephrine).
-- Predisposing Conditions. Individuals with pre-existing diseases of the central nervous or cardiovascular system may have increased susceptibility to the effects of Freons (Dupont, 1996A; OSHA, 1998; Dupont, 1996B; Dupont, 1996D). Persons exposed to epinephrine or other sympathomimetic amines, e.g., bronchodilators and nasal decongestants (e.g., Sudafed •), might be at increased risk for the cardiotoxic effects of Freons (Reprotext, 2003).
-- Special Concerns for Children. Children may inhale relatively larger doses of Freon because, relative to their body weight, they have a greater lung surface area and larger minute volume than adults. Since Freon has a high vapor density, children could also receive high doses due to their short stature and the higher levels of Freon vapor that may be present near the ground when Freon is spilled.

Ref: September 24, 2003 (Revised) - FREON [11, 12, 113]. Technical Support Document: Toxicology. Clandestine Drug Labs/ Methamphetamine. Volume 1, Number 11. California EPA, Office of Environmental Health Hazard Assessment (OEHHA), Department of Toxic Substances Control.

Leukemia (click on for all fluorinated pesticides)

-- Dichlorodifluoromethane ... /was/ tested by inhalation on Sprague-Dawley rats and Swiss mice. The animals were exposed for 4 hr a day, 5 days a week; rats were exposed for 104 weeks, and mice were exposed for 78 weeks. Animals were observed until spontaneous death. Exposure of rats to dichlorodifluoromethane resulted in no noticeable differences in the incidence of total benign and malignant tumors, and of the most frequently expected or rate of tumors. Exposure of mice to dichlorodifluoromethane resulted in a higher number of total tumors in males and females which was dose related in males, pulmonary adenomas in males and females at 5000 ppm, and leukemias in males at 5000 and 1000 ppm and in females at 1000 ppm. [Maltoni C et al; Annals of the New York Academy of Sciences 534: 261-82 (1988)]
Ref: Profile from Hazardous Substances Data Bank for Dichlorodifluoromethane.
http://www.fluoridealert.org/pesticides/Dichlorodifluorometh.TOXNET.htm

Liver (click on for all fluorinated pesticides)

-- Pathologic liver changes were reported in guinea pigs chronically exposed (continued for 90 days; or eight hr daily, 5 days weekly, for six wk) to F 12 at levels of about 4,000 mg/cu m (0.08 % by vol). [USEPA; Ambient Water Quality Criteria Doc: Halomethanes p.C-52-5 (1980) EPA 440/5-80-051]
-- Short-term inhalation studies have been reported for CFC-11, CFC-12, CFC-112, CFC-113, CFC-114, and CFC-115. The results showed low toxicity, and the effects observed were related mainly to the CNS, respiratory tract, and the liver. Oral toxicity studies have confirmed the low toxicity. [WHO; Environmental Health Criteria 113: Fully Halogenated Chlorofluorocarbons p.18 (1990)]
Ref: Profile from Hazardous Substances Data Bank for Dichlorodifluoromethane.
http://www.fluoridealert.org/pesticides/Dichlorodifluorometh.TOXNET.htm

Lung (click on for all fluorinated pesticides)

-- 11 subjects (7 being maintenance technicians of large cooling and refrigerating systems) were exposed for 130 min to CFC-12 (weighted exposure 0.46, 49.9, and 87.7 g/cu m. ... This led to acute reduction of ventilatory lung capacity only at the two highest CFC-12 concentrations, under which conditions a significant decrease in the heart frequency was also observed. [WHO; Environmental Health Criteria 113: Fully Halogenated Chlorofluorocarbons p.90 (1990)]
-- Ten subjects /were exposed/ to CFC-11, CFC-12, CFC-114, two mixtures of CFC-11 and CFC-12, and a mixture of CFC-12 and CFC-114 (breathing concentrations between 16 and 150 g/cu m) for 15, 45, or 60 seconds, and found significant acute reduction of ventilatory lung capacity (FEV50, FEF25) on exposure to each chlorofluorocarbon, as well as bradycardia and increased variability in heart rate in seven subjects, negative T-waves in two subjects (one was exposed to CFC-11 and CFC-12), and atrioventricular block in 1 subject (CFC-114). Mixtures exerted stronger respiratory effects than individual chlorofluorocarbon at the same level of exposure. [WHO; Environmental Health Criteria 113: Fully Halogenated Chlorofluorocarbons p.90 (1990)]
-- Dichlorodifluoromethane ... /was/ tested by inhalation on Sprague-Dawley rats and Swiss mice. The animals were exposed for 4 hr a day, 5 days a week; rats were exposed for 104 weeks, and mice were exposed for 78 weeks. Animals were observed until spontaneous death. Exposure of rats to dichlorodifluoromethane resulted in no noticeable differences in the incidence of total benign and malignant tumors, and of the most frequently expected or rate of tumors. Exposure of mice to dichlorodifluoromethane resulted in a higher number of total tumors in males and females which was dose related in males, pulmonary adenomas in males and females at 5000 ppm, and leukemias in males at 5000 and 1000 ppm and in females at 1000 ppm. [Maltoni C et al; Annals of the New York Academy of Sciences 534: 261-82 (1988)]
-- Short-term inhalation studies have been reported for CFC-11, CFC-12, CFC-112, CFC-113, CFC-114, and CFC-115. The results showed low toxicity, and the effects observed were related mainly to the CNS, respiratory tract, and the liver. Oral toxicity studies have confirmed the low toxicity. [WHO; Environmental Health Criteria 113: Fully Halogenated Chlorofluorocarbons p.18 (1990)]
Ref: Profile from Hazardous Substances Data Bank for Dichlorodifluoromethane.
http://www.fluoridealert.org/pesticides/Dichlorodifluorometh.TOXNET.htm

Mutagenic (click on for all fluorinated pesticides)

Significant mutagenic activity of F 12 at 2.47x10+6 mg/cu m (50%) in air in a Neurospora crassa test system. [USEPA; Ambient Water Quality Criteria Doc: Halomethanes p.C-59 (1980) EPA 440/5-80-051]
---- Note from FAN: Dichlorodifluoromethane is also called Freon 12 or F 12.
Ref: Profile from Hazardous Substances Data Bank for Dichlorodifluoromethane.
http://www.fluoridealert.org/pesticides/Dichlorodifluorometh.TOXNET.htm

Tremors/Convulsions (click on for all fluorinated pesticides)

-- Inhalation of Freon compounds at moderate concentrations initially produces CNS anesthetic effects of intoxication and loss of psychomotor coordination. In humans, this effect occurred at levels of 2500 ppm for Freon 113 and 10,000 ppm for Freon 12. Higher concentrations produce marked in coordination, slurring of speech, apprehension, and finally descreasing levels of consciousness. Attendent hypoxia at high concentrations may also produce tremors, convulsions, and cerebral edema. Cardiac sensitization occurs at higher concentrations than initial CNS intoxication. [Haddad, L.M., Clinical Management of Poisoning and Drug Overdose. 2nd ed. Philadelphia, PA: W.B. Saunders Co., 1990. 1281]
-- .. Dogs, monkeys, rats, rabbits & guinea pigs /had continuous exposure/ to 810 ppm of FC 12, 24 hr daily for 90 days. No deaths were attributed to exposure and pathologic changes ... occurred only in guinea pigs, who showed microscopic liver injury. ... At 200,000 ppm, guinea pigs, dogs and monkeys exposed some 40 hr weekly for 10-12 weeks showed generalized tremors and other signs of mild /CNS depression/, as well as slight blood changes, but no pathologic effects. [American Conference of Governmental Industrial Hygienists. Documentation of the Threshold Limit Values and Biological Exposure Indices. 5th ed. Cincinnati, OH:American Conference of Governmental Industrial Hygienists, 1986.]
-- DOGS, MONKEYS, & GUINEA PIGS EXPOSED TO 20% OF GAS IN AIR FOR SEVERAL HR A DAY FOR SEVERAL DAYS SHOWED TEMPORARY INTOXICATION WITH TREMORS, ATAXIA, AND TENDENCY TO STARE, SALIVATE, & LACRIMATE, BUT NO CUMULATIVE TOXIC EFFECT & NO SPECIFIC OCULAR DISTURBANCE. [Grant, W.M. Toxicology of the Eye. 3rd ed. Springfield, IL: Charles C. Thomas Publisher, 1986. 322]
Ref: Profile from Hazardous Substances Data Bank for Dichlorodifluoromethane.
http://www.fluoridealert.org/pesticides/Dichlorodifluorometh.TOXNET.htm

Environmental (click on for all fluorinated pesticides)

US EPA: Class 1 Ozone-Depleting Substance. Lifetime of Global Warming Potential: 100 years
Ref: http://www.epa.gov/ozone/ods.html
Environmental Contamination Concerns
A. Surface Water. Volatilization from water surfaces is expected to be an important fate process with estimated volatilization half-lives for a model river and a model lake being four hours and five days, respectively. Hydrolysis is not expected to occur. Bioconcentration in organisms is low to moderate; BCF (Bioconcentration factor: the ratio of the chemical concentration in the organism to that in surrounding water) is from 11-86. Biodegradation, adsorption to sediment, and abiotic degradation are insignificant. Large volumes of Freon may sink to the bottom and gradually bubble up to the surface if the water is not too cold (Hazardtext, 2003B; HSDB, 2001A; HSDB, 2001B).
B. Groundwater. In general, Freons that are spilled onto soil have the potential to leach into groundwater, because they do not bind well to soil (Hazardtext, 2003B; HSDB, 2001A; HSDB, 2001B). Fully halogenated hydrocarbons such as Freons 11, 12, and 113 are very resistant to chemical and biological degradation and are likely to be persistent contaminants if they reach groundwater.
D. Soil. If Freon is spilled onto soil, a portion may evaporate from the surface and the remainder will leach downward into the soil. Mobility through the soil is expected to be moderate based on estimated Koc values. Freon does not bind well to soil, and leaching to groundwater is possible (Hazardtext, 2003B; HSDB, 2001B).
E. Air. Once released to air, Freon exists solely as a gas. In the atmosphere, fully halogenated Freons diffuse to the troposphere, where they are very stable and can be transported great distances. Wet deposition may result in some loss, but re-volatilization into the atmosphere is likely. The only degradation process is diffusion to the stratosphere, where photolytic destruction of Freons results in depletion of stratospheric ozone, thereby increasing the amount of ultraviolet-B (UV-B) radiation reaching the earth’s surface (Hazardtext, 2003B; HSDB, 2001A; HSDB, 2001B).

Ref: September 24, 2003 (Revised). Released November 7, 2003) - FREON [11, 12, 113]. Technical Support Document: Toxicology. Clandestine Drug Labs/ Methamphetamine. Volume 1, Number 11. California EPA, Office of Environmental Health Hazard Assessment (OEHHA), Department of Toxic Substances Control.

Many gases emitted as a result of industrial and agricultural activities can accumulate in the earth's atmosphere and ultimately contribute to alterations in the vertical distribution and concentrations of stratospheric ozone. Among the most important are those trace gases that have long residence times in the atmosphere. This allows accumulation in the troposphere and a gradual upward migration of the gases into the stratosphere where they contribute to depletion of stratospheric ozone layer. The atmospheric and chemical processes involved are extremely complex. Trace gases of particular concern include certain long lived chlorofluorocarbons, such as CFC-11, CFC-12, and CFC-113. Since the transport of these gases to the stratosphere is slow, their residence times there are long, and the removal processes are slow, any effect on stratospheric ozone already seen is probably the result of anthropogenic emissions of these gases several decades ago. Those gases already in the atmosphere will continue to exert stratospheric ozone depletion effects well into the next century. /Chlorofluorocarbons/ [WHO; Environmental Health Criteria 113: Fully Halogenated Chlorofluorocarbons p.47 (1990)]
-- The realization that certain chlorofluorocarbons can accumulate in the upper atmosphere and deplete the earth's ozone layer has had a major impact on chemicals like dichlorodifluoromethane which are used in large quantities and have the stability to reach the stratosphere. Uses such as propellants in aerosols which had accounted for about 75% of the release of dichlorodifluoromethane and trichlorofluoromethane, the chemicals of greatest concern (refrigerants and foams accounted for about 14 and 12%, respectively), were banned in the US after Dec 15, 1978(1). Previously dichlorodifluoromethane was the principal propellant for non-food aerosols(1) and 60% of dichlorodifluoromethane and trichlorofluoromethane production went into aerosols(1). [(1) Smart BE; Kirk Othmer's Encycl Chem Tech 3rd NY,NY: Wiley Interscience 10: 829-70 (1980)]

Ref: Profile from Hazardous Substances Data Bank for Dichlorodifluoromethane. http://www.fluorideaction.org/pesticides/dichlorodifluorometh.toxnet.htm

 

 
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