High-Temperature Soup Foods in Plastic Packaging Are Associated with Phthalate Body Burden and Expression of Inflammatory mRNAs: A Dietary Intervention Study

Plastic packaging material is widely used to package high-temperature soup food in China, but this combination might lead to increased exposure to phthalates. The health effects and potential biological mechanisms have not been well studied. This study aimed to examine urinary phthalate metabolites and the expression of inflammatory cytokines in the blood before, during, and after a "plastic-packaged high-temperature soup food" dietary intervention in healthy adults. The results showed that compared with those in the preintervention period, urinary creatinine-adjusted levels of monomethyl phthalate (MMP), mono-n-butyl phthalate (MBP), mono-isobutyl phthalate (MIBP), and total phthalate metabolites in the intervention period were significantly higher, with increases of 71.6, 41.8, 38.8, and 29.8% for MMP, MBP, MIBP, and the total phthalate metabolites, respectively. After intervention, the mean levels of IL-1β, IL-4, and TNF-α mRNA increased by 19.0, 21.5, and 25.0%, respectively, while IL-6 and IFN-γ mRNA decreased by 24.2 and 32.9%, respectively, when compared with the preintervention period. We also observed that several phthalates were associated with the mRNA or protein expression of IL-8, TNF-α, and IL-10. Therefore, consumption of plastic-packaged high-temperature soup food was linked to increased phthalate exposure and might result in significant changes in mRNA expression of several inflammatory cytokines.