JACC Report 46 – 1-Chloro-1,2,2,2-tetrafluoroethane (HCFC 124) Second edition

JACC 046 : 1-Chloro-1,2,2,2-tetrafluoroethane (HCFC 124) CAS No. 2837-89-0 (Second Edition) | November 2004

This report has been produced as part of the ECETOC Joint Assessment of Commodity Chemicals (JACC) programme. It updates an earlier ECETOC review ^aand presents a critical evaluation of the available toxicity and ecotoxicity data on 1 chloro 1,2,2,2 tetrafluoroethane (HCFC-124), including results of recent and unpublished toxicological studies conducted under the Programme for Alternative Fluorocarbon Toxicity Testing (PAFT) ^b. A non-flammable colourless gas, HCFC-124 is used as a replacement for some fully halogenated chlorofluorocarbons in refrigeration. In the atmosphere, HCFC-124 has a low ozone depletion potential of 0.022 relative to trichlorofluoromethane (CFC-11). Its overall lifetime is 5.8 years and its global warming potential 599, relative to carbon dioxide. HCFC-124 has a low order of acute inhalation toxicity in experimental animals; the main effect is weak anaesthesia. HCFC-124 can induce cardiac sensitisation at high concentrations (26,000 ppm; 145,000 mg/m³ and above). In long-term studies at concentrations as high as 50,000 ppm (279,000 mg/m³), rats and mice showed minimal toxic effects attributable to HCFC-124. There were no developmental effects at that exposure level, but there was minimal toxicity to the mother at 15,000 ppm (83,700 mg/m³) and above. HCFC-124 was not mutagenic in bacteria (Ames test), in yeast and cultured mammalian cells in vitro or in the mouse micronucleus (in vivo) assay. These data and the absence of long-term, compound-related tumorigenesis suggest that HCFC-124 is unlikely to present a carcinogenic hazard. There are no reported effects of HCFC-124 in humans. Although there are no experimental data, the predicted toxic concentration of HCFC-124 to either aquatic or terrestrial organisms is relatively high (more than 90 mg/l). In view of that, there should be no significant effects on organisms in the environment.