Parabens including methyl-(MeP), ethyl-(EtP), and propyl-(PrP) parabens, are widely used as antimicrobial preservatives in foods, cosmetics, and personal care products (CPCPs), and drugs. However, studies evaluating the contribution of exposure sources to paraben exposure are limited, and most focus primarily on CPCPs. This study conducted a crossover intervention to assess the contributions of foods and CPCPs to paraben exposure among young Korean adults. Twenty-seven college students participated in a 6-day intervention. They used preservative-free CPCPs throughout the study and were served a 'diet with paraben-free sauces' on days 3-4, followed by a 'diet with paraben-containing sauces' on days 5-6. Urine samples collected at each intervention point were analyzed for nine parabens, including MeP, EtP, and normal propyl-paraben (nPrP), using HPLC-MS/MS. Before the intervention, the geometric mean urinary concentrations of MeP, EtP, and nPrP were 6.05, 76.9, and 0.52 ng/mL, respectively-approximately 3 to 14 times higher than levels reported in other countries. No significant changes in urinary paraben concentrations were observed after the CPCPs-only intervention. However, following the diet with paraben-free sauces, urinary EtP levels significantly decreased by 79.7% (95% CI -89.2, -61.8). After diet with paraben-containing sauces, urinary EtP and MeP levels increased significantly (EtP 2830% (1310-5990)
MeP 84.4% (25.7, 170)). This study highlights the substantial impact of diet on paraben exposure, especially EtP, suggesting that dietary sources play a significant role.