Estimation of Phthalic Acid Esters Pollution Caused from Plastic Worms in Ashinoko Lake, Japan

Determination of phthalate esters in plastic worms taken from Ashinoko lake in Japan was carried out in this study to estimate their pollutants in the lake environment. The phthalate esters in the plastic worms were identified by GC-MS. Di-2-ethylhexyl phthalate (DEHP), diisononylphthalate (DINP), and di-2-ethylhexyl adipate (DEHA) were identified in the plastic worms (n=13) taken from the lake Ashinoko and commercial ones (n=8). The concentration of plasticizer released into the lake environment were 2.9 ± 0.75% for DEHA, 4.9 ± 3.3% for DEHP, and 6.3 ± 1.4% for DINP. The contents of DEHP in the former and the latter were found to average 4.9% (weight) (n=13) and 21% (weight) (n=2), respectively. It might be estimated that the migration of DEHP from the commercial worm material into the lake might account for 77%. Recently, one of plasticizer, DINP is widely used in consumer products as a substitute for other plasticizers prohibited. Therefore, detected DINP in plastic worms taken from the lake Ashinoko, Japan suggested that it might be polluted ecosystem considerably.