Residue levels of phthalic acid esters (PAEs) and diethylhexyl adipate (DEHA) in various industrial wastewaters

Many phthalic acid esters (PAEs), including DMP, DEP, DBP, BBP, and DEHP, as well as DEHA are widely used as plasticizers in plastics. An analytical method was developed and used to analyze these compounds at 41 industrial facilities. The coefficient of determination (R-2) for each constructed curve was higher than 0.98. The method detection limit (MDL) values were 0.4-0.7 mu g/L for PAEs and 0.6 mu g/L for DEHA. In addition, the recovery rate was shown to be 77.0-92.3%, while the relative standard deviation was shown to be in the range of 5.8-10.5%. DMP (n = 3), DEP (n = 2), DBP (n = 2), BBP (n = 2), and DEHA (n = 3) were detected in the range of 2.2-11.1% in the influent. DEHP was a predominant compound and was detected at > MDL in both the influent (n = 16, 35.6%) and the effluent (n = 4, 10.0%) at a high removal efficiency (92-100%). The highest levels of residue in industrial wastewater influent were 137.4 mu g/L of DEHP at plastic products manufacturing facility, 12.5 mu g/L of DEHA at a chemical manufacturing facility, and 14.0 mu g/L of DEP at an electronics facility. The highest concentration of effluent was 12.5 mu g/L of DEHP at a chemical manufacturing facility, which indicated that the effluent was below the allowable concentration (800 mu g/L). Therefore, the levels of PAEs and DEHA that are discharged into nearby streams could not influence the health of the ecosystem.