[Pollution Characteristics and Risk Assessment of Organophosphate Esters in Rivers and Water Body Around Taihu Lake].

To explore the pollution characteristics, potential sources, and ecological and health risk of organophosphate eaters (OPEs) in the surface water of Taihu Lake, water samples from 18 surrounding rivers were collected, as well as 11 water samples from Taihu Lake. The concentrations of 13 OPEs in the water were determined using UPLC-MS/MS, and the spatial distribution of the OPEs in surface water of Taihu Lake basin was further analyzed. The results indicate that, in addition to tripropyl phosphate (TPrP), 2-ethylhexyl diphenyl phosphate (EHDPP), and tricresyl phosphate (TCrP), ten OPEs were detected in all the water samples, the total concentration (ΣOPEs) ranged from 152.5 ng·L-1 to 2524 ng·L-1, and the concentration median value was 519.2 ng·L-1. Tri(chloropropyl) phosphate (TCPP) and tri(2-chloroethyl) phosphate (TCEP) were the dominant OPEs, with the concentration ranges of 73.7-1753.9 ng·L-1 (medium value:204.6 ng·L-1) and 43.9-313.5 ng·L-1 (medium value:131.3 ng·L-1), respectively. The ΣOPEs decreased from the northwest region to the southeast, which corresponds to the economic and industrial development. The results of the source identification reveal that the wastewater discharge from electronics and textile enterprises, construction materials, and vehicular and marine traffic emissions may be the principal sources of the OPEs in Taihu Lake. The ecological risk assessment results indicate that only TCPP, tri(dichloropropyl) phosphate (TDCP), and triphenyl phosphate (TPhP) in some sites had a low risk. The health risk assessment reveals that there were no risks based on water intake, but the long-term risk of OPEs to the aquatic ecosystem and surrounding residents still need attention.

[Pollution Characteristics and Risk Assessment of Typical Organophosphate Esters in Beijing Municipal Wastewater Treatment Plant and the Receiving Water].

Organophosphate esters (OPEs) are ubiquitous in the environment and pose a potential threat to ecosystems and human health. A method for the determination of eight OPEs by ultra-performance liquid chromatography-tandem mass spectrometer (UPLC-MS/MS) was established. The recovery rates of eight target compounds with different solid-phase extraction columns, different eluents, and different eluent volumes were compared. The results showed that using ENVI-18 column enrichment, OPEs were eluted with 8 mL acetonitrile containing 25% (volume fraction) dichloromethane, and the labeled recovery rate of the target compound was 92.5%-102.2%. The recoveries of different matrix samples were 88.5%-116.1% and relative standard deviation was 1.7%-9.9%. The concentration range of 8 different detectable organophosphate esters in the effluent of sewage treatment plant is 85.9-235.4 ng·L-1 during the six-day sampling process, permissive river downstream of the six-day ΣOPEs average total concentration was 130.3 ng·L-1, higher than the 119.4 ng·L-1 upstream water concentration, but lower than the sewage treatment plant effluent concentration of total 162.5ng·L-1. The study shows that the sewage treatment plant cannot completely remove OPEs; for triethyl phosphate (TEP) and 3 (2-ethyl hexyl) phosphate ester (TEHP) there exists a negative removal phenomenon, whereas for other OPEs the removal rate was between 14.1% and 84.9%, and the total ΣOPEs removal rate by the sewage plant was 50.0%. The TPhP in the effluent of the sewage treatment plant has medium environmental risk (RQ>0.1), and other organophosphates have low environmental risk (RQ<0.1); however, the long-term mixing effects of organophosphate esters on the ecosystem of the receiving river should not be ignored.