Histopathological effects of maternal hair dye use on the cornea

Abstract

The aim of this study is to investigate and compare the histopathological effects of hair dye additives, 2- amino-5-nitrophenol (2A5NP) and 2-nitro-p-phenylendiamin (2NPPD) on cornea of neonates from pregnant rats that have been administered these additives subcutaneously. The study included 90 neonates of 26 nulligravida wistar-albino rats among which ten were given 100 mg/kg/day 2A5NP (Group I), ten rats received 150 mg/kg/day 2NPPD (Group II) and control rats received saline (Group III) injections subcutaneously between 7th and 15th gestational days. No sign of toxicity was observed during the treatment and there was no gross abnormality in both the study and control groups. Histopathological
changes of cornea were seen in 22 of 30 newborn rats in Group I (73.4%), in 23 of 30 rats in Group II (76.7%) and only 5 of 30 rats in the control saline injected Group III (16.7%). Histopathological effect of the two additives were statistically significant when compared to the control group (Chi-square:27.63, p = 0.0001), but there was no difference between the effects of 2A5NP and 2NPPD additives on cornea (Chisquare: 0.089, p = 0.766). The present experimental study on rats confirmed the histopathological effect of 2A5NP and 2NPPD on cornea beyond doubt. In the light of which, we can speculate that maternal exposure of hair dyes during pregnancy has some teratogenic effects on newborn rat cornea.