Toxicity evaluation of degradation products of refrigerants

Abstract

The present paper summarizes the data available in the literature concerning toxicity of the degradation products of 1,1,1,2-tetrahydrofluoroethane (HFC-134a), which is widely used worldwide as a refrigerant, and 2,3,3,3-tetrafluoropropene (HFO-1234yf), which is developed as a refrigerant for new generation. There are many studies available for toxic effects of carbon dioxide CO₂) and carbon monoxide (CO) in humans and animals. General toxicity of excessive CO₂ exposure in humans is well reported. However, information on reproductive and developmental toxicity of CO₂ in humans and animals is inadequate for risk assessment. As for CO, further studies are required to evaluate the adverse effects of chronic exposure to low and near ambient levels of CO on development of fetuses and newborn infants in marginal condition because of high susceptibility to hypoxic effect in fetuses and newborn infants. There is a lack of information on toxicity of trifluoroacetic acid, carbonyl fluoride, hydrogen fluoride, and formic acid in humans and animals. Animal studies remain necessary for risk assessment of chemicals because it is difficult to find alternative methods to determine the toxic effect of chemicals.