Urban-rural and regional inequalities in PCDD/F exposure across China's urban agglomerations: Insights from a multimedia food-chain model with cooking bioaccessibility

Ying Li; Xianwen Wu; Nazupar Sidikjan; Yuru Chen; Ye Li; Jing Yang; Nan Lin; Huizhong Shen; Min Liu; Ye Huang

doi:10.1016/j.envpol.2026.128288

Urban-rural and regional inequalities in PCDD/F exposure across China's urban agglomerations: Insights from a multimedia food-chain model with cooking bioaccessibility

Environ Pollut. 2026 Jul 1:400:128288. doi: 10.1016/j.envpol.2026.128288. Epub 2026 May 6.

Authors

Ying Li¹, Xianwen Wu¹, Nazupar Sidikjan¹, Yuru Chen¹, Ye Li¹, Jing Yang¹, Nan Lin², Huizhong Shen³, Min Liu¹, Ye Huang⁴

Affiliations

¹ Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographic Sciences, East China Normal University, 200241, Shanghai, China.
² Institute of Environment and Ecology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, China.
³ State Key Laboratory of Soil Pollution Control and Safety, Shenzhen Key Laboratory of Precision Measurement and Early Warning Technology for Urban Environmental Health Risks, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, China.
⁴ Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographic Sciences, East China Normal University, 200241, Shanghai, China. Electronic address: huangye@geo.ecnu.edu.cn.

PMID: 42103003
DOI: 10.1016/j.envpol.2026.128288

Abstract

Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) are highly toxic, persistent organic pollutants that bioaccumulate through food webs and constitute a major human exposure pathway. National-scale dietary exposure assessments in China remain uncertain due to limited monitoring data, assumptions of complete bioaccessibility, and heterogeneity in regional emissions and dietary patterns. In this study, we developed a China-specific multimedia food-chain model to quantify environmental transfer, food-chain accumulation, and human exposure of PCDD/Fs across six major urban agglomerations, including the Beijing-Tianjin-Hebei (BTH), Yangtze River Delta (YRD), and Pearl River Delta (PRD). The model integrates regional environmental concentrations, population dietary patterns, and cooking-related bioaccessibility for more accurate exposure estimation. Model predictions agree well with observations (n = 224), with 87.9% of mass concentrations and 91.5% of toxic equivalents (TEQs) within one order of magnitude, and significant correlations (r = 0.60 for mass and r = 0.84 for TEQ). BTH, YRD, and PRD regions exhibited the highest contamination and exposure levels, reflecting intensive industrial activities. Animal-derived foods dominated dietary exposure (∼92.7%), mainly eggs, milk, fish, and pork. Urban populations experienced 1.92-6.51 times higher exposure than rural populations, with larger disparities in industrialized regions. Children aged 2-5 years had the highest exposure. Incorporating cooking-related bioaccessibility reduced the daily dose by 86.6 ± 1.7%, 75.7 ± 0.62%, and 80.6 ± 0.95% under boiling, frying, and Chinese-style cooking, respectively. This study highlights spatial disparities in dietary exposure and the importance of considering cooking processes in exposure assessments, providing insights for region-specific food safety management and pollution control.

Keywords: Cooking bioaccessibility; Dietary exposure; Health risk; Multimedia food-chain model; PCDD/Fs; Urban–rural disparity.

MeSH terms

China
Cities
Cooking
Dibenzofurans, Polychlorinated / analysis
Dietary Exposure* / statistics & numerical data
Environmental Exposure* / statistics & numerical data
Environmental Monitoring
Environmental Pollutants* / analysis
Food Chain*
Humans
Polychlorinated Dibenzodioxins / analysis
Rural Population / statistics & numerical data

Substances

Polychlorinated Dibenzodioxins
Dibenzofurans, Polychlorinated
Environmental Pollutants