Evaluating the blank contamination and recovery of sample pretreatment procedures for analyzing organophosphorus flame retardants in waters

Abstract

Organophosphate esters (OPEs), used as flame retardants and plasticizers, are widely present in environmental waters. Development of accurate determination methods for trace OPEs in water is urgent for understanding the fate and risk of this class of emerging pollutants. However, the wide use of OPEs in experimental materials results in blank interference, which influences the accuracy of analytical results. In the present work, blank contamination and recovery of pretreatment procedures for analysis of OPEs in water samples were systematically examined for the first time. Blank contaminations were observed in filtration membranes, glass bottles, solid phase extraction cartridges, and nitrogen blowing instruments. These contaminations could be as high as 6.4-64 ng/L per treatment. Different kinds of membranes were compared in terms of contamination levels left after common glassware cleaning, and a special wash procedure was proposed to eliminate the contamination from membranes. Meanwhile, adsorption of highly hydrophobic OPEs on the inside wall of glass bottles was found to be 42.4%-86.1%, which was the primary cause of low recoveries and was significantly reduced by an additional washing step with acetonitrile. This work is expected to provide guidelines for the establishment of analysis methods for OPEs in aqueous samples.

Precipitation-induced transport and phase partitioning of organophosphate esters (OPEs) in urban and rural watersheds

“…SPE blanks were more contaminated than ASE blanks, especially with TNBP, chlorinated OPEs and TPP (Table S2 †) likely as a result of sample contact with plastics (e.g., SPE cartridges, PTFE transfer tubes) during the extraction process. 28,29 All samples were blank and recoverycorrected to account for these effects. Due to the loss of four particle phase peak flow samples at MMD during the analysis, reported values for OPEs in the particle phase and total OPEs at this site are likely underestimated.…”