Measurement of metal bioaccessibility in vegetables to improve human exposure assessments: field study of soil–plant–atmosphere transfers in urban areas, South China

Abstract

The quality of cultivated consumed vegetables in relation to environmental pollution is a crucial issue for urban and peri-urban areas, which host the majority of people at the global scale. In order to evaluate the fate of metals in urban soil-plant-atmosphere systems and their consequences on human exposure, a field study was conducted at two different sites near a waste incinerator (site A) and a highway (site B). Metal concentrations were measured in the soil, settled atmospheric particulate matter (PM) and vegetables. A risk assessment was performed using both total and bioaccessible metal concentrations in vegetables. Total metal concentrations in PM were (mg kg): (site A) 417 Cr, 354 Cu, 931 Zn, 6.3 Cd and 168 Pb; (site B) 145 Cr, 444 Cu, 3289 Zn, 2.9 Cd and 396 Pb. Several total soil Cd and Pb concentrations exceeded China's Environmental Quality Standards. At both sites, there was significant metal enrichment from the atmosphere to the leafy vegetables (correlation between Pb concentrations in PM and leaves: r = 0.52, p < 0.05) which depended on the plant species. Total Cr, Cd and Pb concentrations in vegetables were therefore above or just under the maximum limit levels for foodstuffs according to Chinese and European Commission regulations. High metal bioaccessibility in the vegetables (60-79 %, with maximum value for Cd) was also observed. The bioaccessible hazard index was only above 1 for site B, due to moderate Pb and Cd pollution from the highway. In contrast, site A was considered as relatively safe for urban agriculture.

Lead, Cadmium, and Arsenic Bioaccessibility of 24 h Duplicate Diet Ingested by Preschool Children Attending Day Care Centers in Brazil

“…Additionally, the atmospheric particulate material that sets down on plants’ surfaces can contaminate them. Xiong et al [22] found that vegetables are high in lead and cadmium concentrations originating from air pollution. Industrial particulate contributes to 25% to 40% of total PTEs concentration, which deposits on plants’ leaves and is absorbed through their vascular system.…”

“…Industrial particulate contributes to 25% to 40% of total PTEs concentration, which deposits on plants’ leaves and is absorbed through their vascular system. Waste incineration and traffic flow contribute to particulate material emission as well [22]. The diet is considered a relevant source for some toxicants.…”

“…The fraction of a contaminant that is released from the food matrix into the digestive fluid and is, therefore, available for intestinal absorption is the bio-accessible fraction of that component [7]. The bio-accessibility determination of contaminants ingested through food allows a better evaluation of the potential health risks and avoids overestimation [21,22]. Therefore, the aim of this study was to determine, through a 24-h duplicate diet method, the bio-accessible fraction of lead, cadmium, and arsenic from the diet of preschool children attending two day care centers (DCC) in Sao Paulo, Brazil.…”

Histopathological Changes and Antioxidant Enzymes Status in Oxidative Stress Induction Using Sodium arsenite in Rats

“…4 Long time exposure to arsenic results in its accumulation in muscles, nails, hair, and skin which leads to different complications and disorders. 5,6 The complications of arsenic poisoning about the heart will cause prolonged and severe abnormal cardiac repolarization, resulting in a fatal arrhythmia. 7 It will also cause coronary heart disease and peripheral vascular disease in humans.…”

A comparison of technologies for remediation of heavy metal contaminated soils

“…Atmospheric deposition (As, Pb, Cr, Hg, Cu, Cd and U) 4. Soil heavy metal(loid)s pollution, food-chain contamination and human health Consumption of food contaminated with heavy metal(loid)s is considered to be the major pathway (N 90%) of human exposure compared to dermal contact or inhalation (Mombo et al, 2015;Xiong et al, 2016b). Soil is the direct path way for the contamination of heavy metal(loid)s in vegetables and crops via root uptake .…”