Abstract

The present paper summarizes the results of animal studies on the reproductive and developmental toxicity of the degradation products of refrigerants, including trifluoroacetic acid (TFA), carbon dioxide (CO(2)), carbon monoxide (CO), carbonyl fluoride (CF), hydrogen fluoride (HF) and formic acid (FA). Excessive CO(2) in the atmosphere is testicular and reproductive toxic, embryolethal, developmentally neurotoxic and teratogenic in experimental animals. As for CO, maternal exposure causes prenatal and postnatal lethality and growth retardation, skeletal variations, cardiomegaly, blood biochemical, immunological and postnatal behavioral changes, and neurological impairment in offspring of several species. Very early studies of CO in rats and guinea pigs reported fetal malformations in exposed dams. The results of toxicological studies on sodium fluoride (NaF) were used to obtain insight into the toxicity of CF and HF, because CF is rapidly hydrolyzed in contact with water yielding CO(2) and HF, and NaF is similar in kinetics and dynamics to HF. Increased fetal skeletal variation, but not malformation, was noted after the maternal administration of NaF. Rat multiple-generation studies revealed that NaF caused retarded ossification and degenerative changes in the lung and kidney in offspring. There is a lack of information about the toxicity of TFA and FA.

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