Laboratoire de Chimie Physique, Université Félix Houphouët Boigny, Abidjan, Côte d'Ivoire.
Centre de Recherches Océanologiques (CRO), Abidjan, Côte d'Ivoire.
Arch Environ Contam Toxicol. 2018 Oct;75(3):449-463. doi: 10.1007/s00244-018-0543-9. Epub 2018 Jul 14.
Despite increasing mining activities, and fertilizer and pesticide use in agriculture, little information is available on the status of metal(loid) contamination in rivers in West Africa. Sixty water samples were collected from three significant rivers (the Bandama, Comoé, and Bia Rivers) in Côte d'Ivoire, the world's top cocoa producer, to examine As, Pb, Cu, Fe, Cd, and Zn concentrations, partitioning, and distribution in suspended particle-size fractions. The results showed higher total metal(loid) concentrations during the dry and flood seasons than during the rainy season. Significant As and Pb concentrations, moderate Cu and Fe concentrations, and low Zn concentrations were observed during the flood season. The metal(loid) concentrations decreased upstream to downstream primarily due to increased deposition through flocculation. Inverse or no obvious spatial trends often were observed, indicative of local contamination from anthropogenic activities. The suspended solid phase and the strength of metal affinity to the particles controlled the metal(loid) concentrations. Furthermore, total metal(loid) concentrations increased significantly with decreasing suspended particle-size fractions. The results underline that As and Pb contents in the Comoé and Bia Rivers threaten the health of at least 3 million people in southeastern Côte d'Ivoire. Filtering river waters before use will significantly reduce human health risks.
尽管采矿活动和农业中化肥及农药的使用不断增加，但有关西非河流中金属（类）污染状况的信息却很少。本研究从科特迪瓦（全球最大的可可生产国）三条重要河流（Bandama 河、Comoé 河和 Bia 河）中采集了 60 个水样，以检测砷、铅、铜、铁、镉和锌的浓度、分配和悬浮颗粒大小分布。结果表明，旱季和雨季的总金属（类）浓度高于雨季。丰水期观察到较高的砷和铅浓度、中等的铜和铁浓度以及较低的锌浓度。金属（类）浓度从上游到下游逐渐降低，主要是由于絮凝作用导致的沉积增加。通常观察到相反或不明显的空间趋势，表明存在人为活动引起的局部污染。悬浮固相和金属对颗粒的亲和力强度控制着金属（类）浓度。此外，总金属（类）浓度随悬浮颗粒大小的减小而显著增加。结果表明，Comoé 河和 Bia 河的砷和铅含量对科特迪瓦东南部至少 300 万人的健康构成威胁。在使用前对河水进行过滤将显著降低人类健康风险。
