Male-mediated F1 effects in mice exposed to nonylphenol or to a combination of X-rays and nonylphenol

Nonylphenol (NP) is an environmental chemical with estrogenic activity. Exposure of the general population to radiation and NP is, very often, unavoidable because of the presence of both agents in the environment of human life and work. The aim of the study was to investigate the effect of subchronic 8-week exposure to NP alone or in combination with X-rays on sperm quantity and quality and on the possibility of the transmission of mutations induced in germ cells to the next generation. Eight-week exposure to NP and X-ray/NP combination diminished sperm count and increased the percent of abnormal spermatozoa, as well as having increased DNA damage in gametes. Some of those effects remained up to 8 weeks after the end of exposure. The exposure of males to 50 mg/kg body weight (b.w.) of NP and to 0.05 Gy + 25 mg/kg b.w. NP daily significantly decreased the percent of pregnant females. The fertilization ability of male mice was not diminished. Combined exposure to low doses of both agents significantly increased the mean number of dead implantations per pregnant female and the percentage of skeletal malformations. Results showed that mutations induced in germ cells by subchronic exposure to NP and to combined X-ray/NP exposure may be transmitted to the F1 generation via sperm.