Concentrations of major and trace elements in the soils, edible parts of crops and urine of farmers in agroecological communities

ABSTRACT. The relationship between soil and health is important for populations that depend on the local environment to meet their nutritional needs. This study aimed to evaluate the concentrations of major and trace elements in the soils, edible parts of crops and urine of farmers in agroecological communities. We collected samples of soil, edible parts of crops and urine of farmers and family members in 23 crop fields in agroecological communities from northeast Brazil. These samples were analyzed to concentrations of Al, As, Ca, Cr, Cu, Fe, Hg, Mg, Zn, and Pb in urine and discriminant analysis and principal component analysis were used to assess the data. Concentrations of potentially toxic elements in soils and crops of agroecosystems were below regulatory levels. Farmers living in agroecological communities present most of the essential and toxic elements in urine within the reference ranges. In general, results showed that urinary concentration of toxic elements among farmers and their families were below allowable limits, which may be due to the agroecological practices.

摘要：土壤与健康的关联对于依赖本地环境满足营养需求的人群而言至关重要。本研究旨在测定农业生态群落中土壤、作物可食用部位以及农户尿液中的常量与微量元素浓度。我们从巴西东北部农业生态群落的23块农田中，采集了土壤、作物可食用部位以及农户及其家庭成员的尿液样本。对上述样本中的尿液成分（包含铝（Al）、砷（As）、钙（Ca）、铬（Cr）、铜（Cu）、铁（Fe）、汞（Hg）、镁（Mg）、锌（Zn）及铅（Pb）等元素）进行了浓度检测，并采用判别分析（discriminant analysis）与主成分分析（principal component analysis）对数据集开展评估。农业生态系统中土壤与作物内的潜在有毒元素浓度均低于监管限值标准。居住于农业生态群落的农户，其尿液中的多数必需元素与有毒元素浓度均处于参考区间内。总体而言，研究结果表明农户及其家庭成员尿液中的有毒元素浓度均低于允许限值，这一现象或与当地采用的农业生态耕作模式有关。