Cd, Pb and Zn Oral Bioaccessibility of Urban Soils Contaminated in the Past by Atmospheric Emissions from Two Lead and Zinc Smelters

Abstract

Ingestion of dust or soil particles could pose a potential health risk due to long-term metal trace element (MTE) exposure. Twenty-seven urban topsoil samples (kitchen garden and lawn) were collected and analyzed for Cd, Pb and Zn using the unified Bioaccessibility Research Group of Europe (BARGE) method (UBM) test to estimate the human bioaccessibility of these elements. The quantities of Cd, Pb and Zn extracted from soils indicated, on average, 68, 62 and 47% bioaccessibility, respectively, in the gastric phase and 31, 32 and 23% bioaccessibility, respectively, in the gastro-intestinal phase. Significant positive correlations were observed between concentrations extracted with UBM and total MTE contents. Stepwise multiple regression analysis showed that human bioaccessibility was also affected by some physico-chemical soil parameters (i.e. total nitrogen, carbonates, clay contents and pH). The unified test presents some valuable data for risk assessment. Indeed, the incorporation of oral bioaccessible concentrations into risk estimations could give more realistic information for health risk assessment.

The relationship between soil geochemistry and the bioaccessibility of trace elements in playground soil

“…Compared to similar studies of urban soils which report soil properties, the samples from Madrid playgrounds are OM-and Fe-deficient and have a significantly higher pH (e.g. Juhasz et al 2007;Ljung et al 2007;Poggio et al 2009;Rasmussen et al 2008;Roussel et al 2010;Yang et al 2002).…”

“…Broadway et al (2010) 14. Roussel et al (2010) that raising the pH in the intestinal phase should cause: (a) partial precipitation and enhanced adsorption on mineral colloids and higher absorption in organic matter of cations (i.e. reduced bioaccessibility); and (b) desorption of As, the only trace element that should be present as an anion in the acidic gastric environment, from mineral surfaces and polar groups in organic matter as their density of positive charge decreases (i.e.…”

“…There are many in vitro studies of the bioaccessibility of trace elements in urban soils (Ljung et al 2007;Madrid et al 2008;Poggio et al 2009;Rasmussen et al 2008;Roussel et al 2010). However, the results are variable and sometimes contradictory, and hence, there is little agreement.…”

Total Excess Lifetime Cancer Risk Estimation from Enhanced Heavy Metals Concentrations Resulting from Tailings in Katsina Steel Rolling Mill, Nigeria

“…Arsenic and its compounds are used in herbicides, pesticides and insecticides which may form part of the exposure sources to humans in addition to air, water, cigarette smoking and contaminated food [19,20]. Lead contamination may result from industrial sources such as manufacturing activities and lead smelting [21]. Lead and some other heavy metals remains a major hazard for human health because of their inherent nature of accumulation and non-bio-degradability especially when they accumulate in the body tissues faster than the body's detoxification pathway can dispose of them [22,23].…”

Measuring the solid-phase fractionation of lead in urban and rural soils using a combination of geochemical survey data and chemical extractions

“…The method generates samples for analysis at the end of the gastric phase extraction, known as 'stomach' and intestinal phase extraction, known as 'stomach and intestine'. Full details of the UBM application to different test soils have been previously described (Broadway et al 2010;Pelfrene et al 2011;Roussel et al 2010;). As a part of its development, which included tightening the pH requirements of the stomach phase pH from 1.2-1.5 to 1.2 and a change in the separation step from centrifugation at 3000g for 5 min to 4500g for 15 min, the UBM has also been validated against a juvenile swine model for As, Cd and Pb (Caboche 2009;Denys et al 2012).…”