Since they are used in a wide variety of ways and can easily dissolve out of the product used, humans are exposed to these substances almost constantly. Organophosphorus flame retardants are frequently measured in indoor air or in high concentrations in house dust. Only a few studies have addressed whether organophosphorus flame retardants can also be absorbed through food.

In the course of the European project HBM4EU, the exposure of children to organophosphorus flame retardants was measured in Belgium, Germany, Denmark, France, Slovenia and Slovakia. For this purpose, either the child's morning urine or a urine sample taken during the course of the day were collected and analyzed for metabolites (biomarkers) of organophosphorus flame retardants. Using these data, the total ingested amount of organophosphorus flame retardants could be calculated. To calculate how much dietary intake contributes to the total organophosphorus flame retardant load, Belgian occurrence data in food were linked to the respective national consumption data. Dietary intake was then compared to total intake. In addition, both total and dietary intakes were compared with available health-based guidance values to assess whether current exposure to organophosphorus flame retardants poses a health risk.

The daily intake of the studied organophosphorus flame retardants tris (2-chloroethyl) phosphate (TCEP), tris (1-chloro-2-propyl) phosphate (TCIPP), and tris (1,3-dichloro-2-propyl) phosphate (TDCIPP) ranged from 0.02 to 0.2 µg/kg body weight/day, 0.05 and 0.17 µg/kg body weight/day, and 0.03 and 0.18 µg/kg body weight/day (summarized for all countries). Dietary intakes for TCEP ranged from 0.02 to 0.2 µg/kg body weight/day, for TCIPP from 0.037 to 0.2 µg/kg body weight/day, and for TDCIPP from 0.005 to 0.09 µg/kg body weight/day. Dietary intake of TCEP contributes 6-57% of total intake (summarized for all countries). For TCIPP, dietary intake exceeds the total measured exposure, except in Belgium and France. The excess intake can be explained by an overestimation of dietary intake or by neglecting another biomarker. Dietary intake of TDCIPP contributes 11-173% to the total burden (summarized for all countries). Both total and dietary intakes exhaust the health-based guideline values only up to 3%.

Taken together, the results suggest that there is a low health risk considering the current state of knowledge of exposure and toxicological data. The study also shows that dietary intake may contribute significantly to the overall exposure of the population to organophosphorus flame retardants. Therefore, on the one hand, studies must be conducted to better estimate dietary exposure and, at the same time, efforts must be made to reduce exposure to organophosphorus flame retardants.

Publication: Plichta, V.; Steinwider, J.; Vogel, N.; Weber, T.; Kolossa-Gehring, M.; Murínová, L.P.; Wimmerová, S.; Tratnik, J.S.; Horvat, M.; Koppen, G.; Govarts, E.; Gilles, L.; Rodriguez Martin, L..; Schoeters, G.; Covaci, A.; Fillol, C.; Rambaud, L.; Jensen, T.K.; Rauscher-Gabernig, E. Risk Assessment of Dietary Exposure to Organophosphorus Flame Retardants in Children by Using HBM Data. Toxics 2022, 10, 234. https://doi.org/10.3390/toxics10050234