Heavy metals in the São Mateus Stream Basin, Peixe River Basin, Paraiba do Sul River Basin, Brazil

Abstract Large-scale enterprises with high potential to pollute need to be licensed, properly supervised and monitored during and after their operations to avoid and/or mitigate impacts in their areas of influence. The São Mateus Stream Basin (SMSB), located in rural area of Juiz de Fora (MG), is impacted by several activities, highlighting a deactivated landfill and an industrial park. This study monitored the concentration of heavy metals in the waters of the main tributaries of the SMSB. Strategic points were selected in each sub-basin, before the mouth and meeting of the Bocaina, Salvaterra and São Mateus Streams, measured monthly between January and December 2014 using the Metalyser probe, and applying the Contamination Index (CI). The CI results showed that the enterprises located in this basin, especially the Park Sul and Salvaterra Landfill in the Bocaina and Salvaterra Streams, respectively, are negatively impacting the quality of these waters. Metals such as Hg, Cu, Pb and Zn were the ones that most violated CONAMA Resolution 357/2005, directing management in order to control the sources of these metals, which are cumulative in organisms and damage the whole trophic chain. The inhabitants of this rural area are not served by any water concessionaire and make use of springs and wells below the level of these streams.

摘要：具有高污染潜力的大型企业需取得合法许可，并在运营期间及运营后接受规范监管与监测，以规避或减缓其对周边影响区域的生态环境影响。位于巴西米纳斯吉拉斯州茹伊斯迪福拉（Juiz de Fora）乡村区域的圣马特乌斯流域（São Mateus Stream Basin, SMSB），受多项人类活动干扰，其中以一处已封场填埋场及一处工业园区的影响最为突出。本研究针对SMSB主要支流的水体重金属浓度开展监测，在Bocaina河、Salvaterra河与圣马特乌斯河汇流前的各子流域战略监测点位布设采样点，于2014年1月至12月期间每月采用Metalyser探头进行现场检测，并运用污染指数（Contamination Index, CI）开展污染评估。污染指数分析结果显示，该流域内的相关企业，尤其是分别位于Bocaina河与Salvaterra河沿岸的Park Sul工业园区及Salvaterra填埋场，对上述水体水质造成了显著负面影响。其中汞（Hg）、铜（Cu）、铅（Pb）及锌（Zn）等重金属的浓度最为显著地超出了巴西国家环境委员会（CONAMA）第357/2005号决议的限值标准，该研究结果可为管控此类重金属污染源提供管理指引——此类重金属可在生物体内累积，并破坏整个水生营养级链。该乡村区域未接入任何供水特许经营服务商的管网，居民仅依靠分布于这些溪流沿岸的泉眼与水井取用地下水。