Heavy metal monitoring dates for river systems in agricultural regions of the southwestern North China Plain

A systematic monitoring network was established across the southwestern agricultural regions of the North China Plain, comprising 70 sampling sites distributed along river systems. The study employed a comprehensive seasonal sampling strategy, collecting a total of 284 samples across all sites during four distinct agricultural seasons (spring planting, summer growth, autumn harvest, and winter fallow) throughout 2021. All samples were analyzed for concentrations of seven heavy metals (Cu, Zn, As, Hg, Cr, Cd, and Pb). The dataset was subsequently subjected to: (1) absolute principal component score-multiple linear regression (APCS-MLR) analysis for source apportionment, and (2) Monte Carlo simulation-based health risk assessment to evaluate.