Urinary organophosphate ester concentrations in relation to ultra-processed food consumption in the general US population

Background: Ultra-processed foods are highly processed foods which are manufactured with industrial substances to increase convenience and palatability. Some organophosphate esters (OPEs) are used as flame retardants and plasticizers and have been detected in food samples, particularly processed foods. However, little is known about dietary sources of OPEs or whether higher consumption of ultra-processed foods increases exposures. Objectives: We evaluated whether higher consumption of ultra-processed food is associated with urinary OPE metabolite concentrations in a nationally representative sample of US children and adults. Methods: Among 2242 participants (≥6 years) in the National Health and Nutrition Examination Survey (NHANES) 2013–2014, we used the NOVA classification system to calculate percent of total energy from ultra-processed food using a 24 h dietary recall. Concentrations of 7 OPE metabolites, including diphenyl phosphate (DPHP), bis(1,3-dichloro-2-propyl) phosphate (BDCPP), bis(2-chloroethyl) phosphate (BCEP), dibutyl phosphate (DBUP), di-p-cresyl phosphate (DPCP), 2,3,4,5-tetrabromobenzoic acid (TBBA), and bis(1-chloro-2-propyl) phosphate (BCPP) were measured in urine. We used multivariable linear or logistic regressions to examine associations per 10% higher total energy from ultra-processed foods with percent changes or prevalence of detectable levels of creatinine-standardized OPEs. Results: In a model adjusting for only urinary creatinine, each 10% higher total energy from ultra-processed food was associated with 3.5% (95% CI: 0.7%, 6.3%) higher DPHP and 8.2% (95% CI: 4.6, 11.9%) higher BDCPP concentrations. However, none of the OPE metabolites was associated with ultra-processed food consumption in models adjusted for sociodemographic characteristics, health behaviors, and BMI (all p-values >0.05). Ultra-processed breads and tortillas; sauces, dressing, and gravies; and milk-based drinks were associated with higher concentrations of BDCPP while frozen and shelf-stable plate meals were associated with lower concentrations. Reconstituted meat or fish products and ultra-processed milk-based desserts were associated with greater odds of detectable levels of BCPP. Conclusion: While some food groups were associated with urinary OPE metabolite concentrations, ultra-processed foods do not appear to be a major source of current OPE exposure in the US.