Human Health Risk Assessment Due to Agricultural Activities and Crop Consumption in the Surroundings of an Industrial Area

The present work integrates concentrations of potentially toxic elements (PTE) (i.e. As, Cd, Cr, Cu, Hg, Ni, Pb and Zn) from (i) environmental media (i.e. soil, crops) and (ii) human hair. The aim was to assess whether agricultural soil and vegetable quality are related to risks to human health from different exposures pathways and if there are any signs of it in human hair. Domestic vegetable gardens in the surroundings Estarreja chemical complex (ECC), Municipality of Estarreja, central Portugal, were the selected for the current study. Data analysis of two soil fractions (2 mm and < 63 mu m) and of three different vegetables (Lycopersicon esculentum Mill., Solanum tuberosum, L. and Brassica oleracea, L.) samples were used. Agricultural soils in the ECC surrounding present high concentrations of As, Cu, Hg and Pb (mg/kg: up to 532, 103, 13.7 and 109, respectively). The high PTE concentrations in soils and horticultural crops are chiefly related to historical industrial activities, mostly from arsenopyrite roasting and a chloralkali plant. The assessment of risks to human health for ECC-surrounding residents (children 4-8 years old; elderly adults > 55 years old) showed that agricultural soil-dust ingestion induces a high-non-carcinogenic risk (HI) for As (HI up to 41 and 4.4, for children and adult, respectively), Pb (HI up to 2.5 for children) and Hg (HI up to 1.3 for children) and carcinogenic risk (CR) for As (10(-3) for both age groups). Exposure through consumption of tomatoes and potatoes grown in the study soils does not present a high health hazard. However, exposure to As through consumption of cabbage presents both carcinogenic and non-carcinogenic health risks for both studied age groups (CR > 10(-4) and HI > 1.1). It is likely that hair As and Hg concentrations increases in both children and adults can be related to the ingestion of agricultural soil and cabbage, and inhalation or dermal contact with contaminated soil. Nonetheless, this assumption requires further investigation, including on other potential sources of contaminants for the local population, such as dietary intake of other foodstuffs. Hair Cr content in the adult group of residents showed maximum values above the normal range for non-exposed individuals, as well as high mean and median values which may be related to the high Cr content in the studied foods. The exposure study results are in agreement with As and Hg concentrations in both children and adults hair and validate it as a biomarker of As and Hg local environmental exposure.