Cytotoxic effect of paraphenylenediamine (PPD) on Danio rerio (Zebra Fish)

Paraphenylenediamine (PPD) is a synthetic chemical widely used as a substitute for henna as a permanent hair dye because it gives a natural look to the hair and the dyed hair can also be shampooed or permed without losing the colour. However, the intermediate and partially oxidized form of PPD is reported to cause adverse reactions in people. Effects of sublethal concentrations of PPD in the zebra fish were examined for 15 days following exposure to the chemical. On the 7th day and the 15th day following the exposure, blood smears were examined for presence of micronuclei using the Giemsa stain. The micronuclei percentage indicating the cytotoxic effect of PPD was significantly greater in the exposed fishes and the extent of toxicity was directly proportional to the concentration of PPD and to the length of exposure. Therefore, waste water reaching any aquatic ecosystem should be monitored for PPD in order to prevent any adverse impacts on the aquatic ecosystem and to minimize the threat to human beings due to biomagnification.