Heavy metal health risks and source analysis of temple dust in typical cities of Henan Province

The study focuses on Tai Shan Temple in Jiawan, Xinxiang City, investigating the concentrations of eight heavy metal elements (Hg, As, Cr, Ni, Cu, Zn, Cd, Pb) in surface dust and conducting health risk assessment and source apportionment of heavy metal pollution. Results reveal spatial variability in the concentrations of seven heavy metal elements (excluding As) in temple surface dust, exceeding the soil environmental background values of the southern Yu Plain. The exceedance rate of Cu concentrations over soil background values at each sampling point reaches 91.03%, with Ni showing an average exceedance rate of 151.1%. Potential carcinogenic and non-carcinogenic risks posed by heavy metals in surface dust to children and adults were found to be below standard values, with Cr and Pb identified as the primary non-carcinogenic factors. Children were found to face higher health risks from heavy metals in surface dust compared to adults, primarily through the hand-to-mouth ingestion pathway. The health risk index of heavy metals exhibited an initial increase followed by a decrease with increasing distance from the furnace core, with peak values generally observed at a gradient of 20 meters. Matrix factor analysis indicated that Hg and Pb in surface dust mainly originated from architectural paint pollution, while Cr, Cu, Ni, and Zn primarily originated from temple incense pollution, and Cd and As were predominantly sourced from agricultural and livestock activities. Temple incense pollution contributed significantly to the pollution sources, accounting for 40.96%, followed by agricultural and livestock pollution at 37.40%, and temple construction pollution at 21.64%.