市售常用染髮劑中成分：對苯二胺(p-phenylenediamine)及對胺基酚(4-aminophenol)對圓水蚤(Daphnia pulex)及其胚胎之影響

Purpose: The present study evaluated whether the hair dye components, p-phenylenediamine and 4-aminophenol, would be embryotoxic to cladoceran Daphnia pulex in the laboratory. Methods: For this study, we developed an in vitro assay system to detect toxic compounds in the aquatic environment containing 5th generation and cladoceran eggs. The eggs were placed in a culture medium containing nature-imitating water (hard water). Then, p-phenylenediamine and 4-aminophenol were added at various doses in a series of experiments in which we performed acute toxicity tests for EC50 values and evaluated embryo toxicity by observing the occurrence of visible morphological embryonic abnormalities. Results: We found both chemicals to be toxic to developing embryos. The threshold concentration for the occurrence of developmental abnormalities on p-phenylenediamine was 0.05 mg/L, and 4-aminophenols 0.03 mg/L. The developmental abnormalities consisted primarily of curved or unextended shell spines, underdeveloped first antennae, and underdeveloped Malpighian tubes. The greater the exposure to the chemicals, the greater the incidence of these abnormalities. Conclusion: We conclude that the commonly used hair dye components, p-phenylenediamine and 4-aminophenol, are chronically toxic to freshwater invertebrate animals.