Embryotoxic effects of benzene and its methyl derivatives: toluene, xylene

Reproductive and Developmental Toxicity of Toluene: A Review

“…The association between toluene exposure and fetotoxicity is also supported by effects on fetal somatic development in several other studies (20)(21)(22)(23)(24), which are summarized in Table 3. Effects oftoluene exposure on late fetal weights and skeletal maturation were reported in rats and mice; data in rabbits are weak.…”

“…A further study by Ungvary and Tatrai demonstrated an increase in the incidence ofweight-retarded fetuses (i.e., < 0.9 g body weight) among dams exposed to 266 ppm toluene via inhalation chambers 3 periods of4 hr on each day between days 6 to 15 ofgestation (20). This index ofdevelopmental retardation was also increased in the fetuses ofdams exposed to 133 ppm toluene in the other study where mean fetal weight was reduced (22).…”

“…Reductions in fetal weights at term were also demonstrated in two studies in which pregnant mice were exposed by inhalation to toluene at 133 ppm for 24 hr/day on days 6 to 13 gestation (22) or by exposure to 1.5 or 3.0 mL/kg via gavage on days 6 to 15 gestation (23). Data from these studies are presented in Table 3.…”

“…In one ofthese studies, fetuses ofrat dams exposed to 399 ppm toluene for 24 hr/day on days I to 8 ofgestation had lower body weights than any other group including two control groups (22). The percentage of weight-retarded (i.e., < 3.3 g body weight) fetuses among these dams was also increased.…”

“…The International Research and Development Corporation (IRDC) study demonstrated a nonsignificant increase in incidence of skeletally-retarded fetuses (SRF) from ratdams exposed subchronically to2000 ppmtoluene for6 hr/day (19) (Table 3). Significantincreases inincidences of SRFamong pregnantrats were reported fromavariety ofexposure scenarios (266 ppm toluene for 8 hr/day on days 1 to 21 ofgestation (22) or for24hr/day ondays 7 to 14ofgestation (21 ) and to 399 ppm toluene for 24 hr/day on days 1 to 8 ofgestation (22).…”