Mutagenicity studies with 2,4,5-T on bacteria and mammalian germ cells

Abstract

The herbicide 2,4,5-T (2,4,5-trichlorophenoxyacetic acid) was evaluated for potential mutagenicity by a Salmonella/mammalian-microsome test, a dominant lethal test on female rats, and by a cytogenetic assay on spermatogonia of Chinese hamster. In the Salmonella/mammalian-microsome test on four Salmonella typhimurium strains (TA 1535, TA 100, TA 1537, and TA 98), doses of up to and including 2500 micrograms/plate did not cause any mutagenic effects. In a dominant lethal test on female rats, 8-week dietary administration of 2,4,5-T at doses of up to and including 10 mg/kg/day did not cause any increase in preimplantation loss or the rate of dead implants, and did not have any effect on the fertilization quota. Cytogenetic analysis of the spermatogonia of male Chinese hamsters orally dosed five times at 24-hr intervals with 2,4,5-T at levels of up to and including 100 mg/kg did not provide any indication of 2,4,5-T having chromosome-damaging effects. Therefore, none of the three test systems provided any indication of 2,4,5-T having a mutagenic effect.

Sister chromatid exchanges among workers occupationally exposed to phenoxy acid herbicides 2,4-D and MCPA

“…Because the numbers of SCEs may vary remarkably between the individual cells within a cell culture, more cells would be necessary for any decisive interpretation of the data. The results of the present study support the earlier data which indicated that 2,4-D and MCPA do not act as agents which damage DNA directly [17][18][19][20]. Recently, however, data have accumulated which suggest that phenoxy acid herbicides may have genotoxic potential via an indirect mode of action.…”