The following abstract presents results of a study conducted by a contract laboratory for the National Toxicology Program. The findings were not evaluated in accordance with the levels of evidence for reproductive or developmental criteria established by NTP in March 2009. The findings and conclusions for this study should not be construed to represent the views of NTP or the U.S. Government.
Sodium nitrite administered via drinking water, was tested for its effects on fertility and reproduction in Swiss CD-1 mice according to the continuous breeding protocol. Based on results of dose-finding studies, 0.06, 0.12, and 0.24% weight per volume sodium nitrite concentrations were chosen to investigate effects on fertility and reproduction. Male and female mice were continuously exposed for a 7-day precohabitation and a 98-day cohabitation period (Task 2). Sodium nitrite treatment had no effect on fertility or any of the reproductive parameters. The water consumption in the 0.24% group was consistently lower but this had no effect on F0 body weights. Since the response was negative in Task 2, the cross-over mating trial (Task 3) to determine the sex affected by chemical treatment was not conducted. The F1 pups from control and 0.24% groups were weaned for second generation studies. Live male and female pup weights were significantly lower on postnatal days 7, 14, and 21 in the 0.24% group. At sexual maturity, fertility was not affected in the F1 mice nor were body weights decreased in either sex. At necropsy, absolute cauda epididymis weight was lower in the treated group by 9%.
Based on the results of the present study, it is concluded that sodium nitrite is not a reproductive toxicant in Swiss CD-1 mice at the levels tested.