2015-Sustainable Industrial Processing Summit
SIPS 2015 Volume 4: Meech Intl. Symp. / Mining Operations
| Editors: | Kongoli F, Veiga MM, Anderson C |
| Publisher: | Flogen Star OUTREACH |
| Publication Year: | 2015 |
| Pages: | 275 pages |
| ISBN: | 978-1-987820-27-0 |
| ISSN: | 2291-1227 (Metals and Materials Processing in a Clean Environment Series) |
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Heavy Metal Contamination of Agricultural Products and Human Exposure Via Food Intake in the Artisanal Gold Mining Province of Portovelo & Zaruma, El Oro State, South Ecuador
Bernardo Ranieri1; Kirsten Dales2; Marcello Veiga1;1UBC-MINING, Vancouver, Canada; 2INDEPENDENT ELEMENT, Vancouver, Canada;
Type of Paper: Regular
Id Paper: 503
Topic: 4
Abstract:
Artisanal and small-scale gold mining (ASGM) utilizes several toxic chemicals in the process and contributes to emissions and releases of heavy metals to the environment. ASGM has been the primary economic activity in the Portovelo & Zaruma mining district, El Oro state, south Ecuador for more than two decades. Large quantities of gold ore have been processed using rudimentary techniques and toxic chemicals, resulting in alarming levels of heavy metals in multiple environmental compartments of urban and rural areas (i.e. soil, water and air). Food is usually the primary source of human exposure to heavy metals. Chronic intake above safe levels can cause several health hazards in humans. Anthropogenic contamination of vegetables may arise by industrial emissions, irrigation, pesticides, harvesting and post-harvest practices. Accumulation occurs by assimilation of gases and suspended particles by leaves and root absorption in heavily polluted soils or sediments. Therefore, the origin of crops and the ecological, social and economic contexts that determine people's access to food and consumption behavior may influence exposure through the diet. Differential food sources may create unequal vulnerabilities to intake of toxic contaminants. In this project, we evaluate the potential health risks by heavy metal intake via food in four communities of the Portovelo & Zaruma mining district. We tested the hypothesis that heavy metal exposure differs between food sources from contrasting ecosystem integrity levels. We characterize food sources (i.e. types of local markets and production systems) and assess potential contamination pathways in the studied landscapes using spatial modeling tools. We compare predictive spatial patterns with heavy metal concentrations in food and soil samples. We discuss the links between ecosystem structure, buffering capacity and resilience to contamination aiming at informing policies for mitigation and remediation actions to reduce human health risks in these ASGM communities.