Occurrence, distribution and risk assessment of organophosphate ester flame retardants and plasticizers in surface seawater of the West Pacific

Twenty-eight samples of surface seawater were collected from the West Pacific Ocean during 2019 using a high-volume solid-phase extraction with high-throughput organic analysis (Hi-throat/Hi-volume SPE) method, and concentrations of 10 organophosphate ester flame retardants and plasticizers (OPEs) were determined. The total OPE concentration in the samples was 3.02-48.4 ng L-1 (mean 25.0 +/- 10.5 ng L-1), with tris(2-chloroethyl) phosphate (TCEP) being the largest contributor. Cluster analysis results showed off-shore input from the coast of East and Southeast Asia was an important source of these chemicals. Tri-p-tolyl phosphate (TpTP) should also be considered for long-term monitoring, because of its high detection frequency. Results of a risk assessment indicated low ecological risk to species in the West Pacific Ocean for TPhP and Sigma OPEs. Hazard quotients (HQs) were all <1, indicating that the health risk to humans from these chemicals was at acceptable levels.

Automated summary

A study was conducted in 2019 to investigate the concentrations of organophosphate ester flame retardants and plasticizers in surface seawater samples collected from the West Pacific Ocean. The results revealed an important offshore input of these chemicals from the coasts of East and Southeast Asia. The risk assessment showed low ecological risk to species in the West Pacific Ocean, as Hazard Quotients were all <1, indicating acceptable levels of health risk to humans.