title: Acute toxicity of parabens and their chlorinated by-products with Daphnia magna and Vibrio fischeri bioassays.
abstract: The acute toxicity of 21 parabens and their chlorinated derivatives was investigated by means of two toxicity bioassays: Daphnia magna immobilization test and the inhibition of bioluminescence of Vibrio fischeri. The median effective concentration (EC(50)) values of the tested parabens ranged from 2.2 to 62 mg l(-1) in the D. magna test and from 0.0038 to 5.9 mg l(-1) in the V. fischeri test at 15 min after exposure. The toxicity of dichlorinated methyl- and n-propylparaben, the most commonly used preservatives in cosmetics, toward D. magna was 3.9- and 2.8-fold that of their corresponding parent compounds. Toxicity toward D. magna showed a linear relationship with log P, indicating that toxicity increases with increasing hydrophobicity. On the other hand, the correlations of toxicity toward V. fischeri with hydrophobicity and with the degree of chlorination were poor. In addition, the results of the present study indicated that the V. fischeri test was more sensitive than the D. magna test for the determination of the acute toxicity of parabens. A complete assessment of the ecological and toxicological risks of parabens may require the examination of chlorinated parabens as well as the parent pollutants, as described in the present study.
authors.affiliation: Institute for Environmental Sciences, University of Shizuoka, Yada 52-1, Suruga-ku, Shizuoka 422-8526, Japan. terasaki@u-shizuoka-ken.ac.jp
authors.forename: Masanori
authors.initials: M
authors.lastname: Terasaki
authors.forename: Masakazu
authors.initials: M
authors.lastname: Makino
authors.forename: Norihisa
authors.initials: N
authors.lastname: Tatarazako
mesh_terms: D048908:Aliivibrio fischeri / Q000187:drug effects*; D000818:Animals; D001681:Biological Assay; D003621:Daphnia / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D054750:Ecotoxicology; D054879:Halogenation; D057927:Hydrophobic and Hydrophilic Interactions; D007928:Lethal Dose 50; D049449:Luminescence; D015394:Molecular Structure; D008970:Molecular Weight; D000442:Octanols / Q000737:chemistry; D010226:Parabens / Q000737:chemistry / Q000633:toxicity*; D012680:Sensitivity and Specificity; D023382:Toxicity Tests, Acute; D014867:Water / Q000737:chemistry
chemical_list: D000442:Octanols; D010226:Parabens; D014867:Water