Toxicity of seven phthalate esters to embryonic development of the abalone Haliotis diversicolor supertexta

The toxicity of seven phthalate esters (PAEs), dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), butylbenzyl phthalate (BBP), di-n-hexyl phthalate (DnHP), di-(2-ethylhexyl) phthalate (DEHP) and di-n-octyl phthalate (DOP) to embryogenesis and larval development of the marine univalve Haliotis diversicolor supertexta was examined by means of two-stage embryo toxicity test. At the blastula stage, the normal embryonic development of H. diversicolor supertexta showed a good dose-response decrease when exposed to DMP, DEP, DBP, BBP, and DnHP. 9-h EC50 values of DMP, DEP, DBP, BBP, and DnHP were 55.71, 39.13, 8.37, 2.65, and 3.32 mg/l, respectively. 9-h EC50 values of DEHP and DOP were not available due to their low solubility. The toxicity order of seven tested PAEs was BBP > DnHP > DBP > DEP > DMP > DOP > DEHP. With the completion of metamorphosis as an experimental endpoint, the 96-h no-observed effect concentration values of DBP, DEHP and the other five tested PAEs were 0.022, 0.021, and 0.020 mg/l, respectively. Due to simple obtainment, convenient stimulation to spawn in the lab, greater sensitivity than mature species, and short culture time, the embryos of H. diversicolor supertexta have the potential to be utilized in acute toxicity test for at least PAEs.