Tris(1,3-dichloropropyl) phosphate - Determination of bis(1,3-dichloropropyl) phosphate in urine by...

The working group "Analyses in Biological Materials" of the German Senate Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area (MAK Commission) developed and verified this biomonitoring method for the determination of urinary concentrations of bis(1,3-dichloropropyl) phosphate (BDCPP), which is the major metabolite of tris(1,3-dichloropropyl) phosphate (TDCPP). TDCPP is one of the most commonly used organophosphate flame retardants in cars, residential furniture, and products containing polyurethane foam, and has been detected in dust from private houses, office buildings, and car interiors, suggesting that a majority of the general population is exposed to TDCPP. The aim of this work was to establish a reliable, selective, and sensitive method for the detection of BDCPP in urine. The urine samples are spiked with the internal standard d₁₀-BDCPP and slightly acidified. Cleanup by mixed-mode anion-exchange solid-phase extraction is applied, and BDCPP is detected by liquid chromatography with simultaneous atmospheric pressure chemical ionisation and electrospray ionisation-tandem mass spectrometry. Calibration is carried out in ultra-pure water ∶ MeOH (4 ∶ 1, v/v). Good precision data with standard deviations below 7%, as well as good accuracy data with mean relative recoveries in the range of 93.6-101%, show that the method provides reliable and accurate analytical results. The method is both selective and sensitive, and the limit of quantitation of 0.2 ng BDCPP/l urine is sufficient to determine occupational exposure as well as higher background exposure levels to TDCPP in the general population.