Laguna de Bay is the largest multipurpose lake in the Philippines. Of the primary uses, fish cultivation and potable water production depend mainly on its water quality. Over the years, this tropical lake has been inundated with pollution from agricultural, industrial and domestic wastewaters. While new contaminants have emerged, traditional contaminants including heavy metals continue to threaten the lake’s resources. In this study, the levels and distribution of heavy metals in Laguna de Bay were investigated. Surface water samples from nine sampling sites were analyzed for As, Pb, Cd, Cr, Cu, Co, Ni, and Mn by ICP-MS and Hg by cold-vapor AAS. These heavy metals are variably dispersed across the lake and the mean concentrations were from below detection limits to 110.7 µg/L. Except for As and Mn, the levels are within the national standards for surface waters. In the south side of the lake near hot springs, As was found in relatively high concentrations up to 116.2 µg/L. The findings of this study on the present-day levels of heavy metals in Laguna de Bay are useful in assessing and sustaining the pollution prevention strategies in this valuable aquatic system that provides natural resources and ecosystem services.

拉古纳湾是菲律宾最大的多功能湖泊。在主要用途中，鱼类养殖和饮用水生产主要取决于其水质。多年来，这个热带湖泊被农业、工业和生活废水的污染所淹没。虽然新的污染物已经出现，但包括重金属在内的传统污染物继续威胁着湖泊的资源。在这项研究中，调查了 Laguna de Bay 中重金属的水平和分布。使用 ICP-MS 分析了来自九个采样点的地表水样品中的 As、Pb、Cd、Cr、Cu、Co、Ni 和 Mn，并通过冷蒸气 AAS 分析了 Hg。这些重金属在整个湖泊中的分布各不相同，平均浓度从低于检测限到 110.7 µg/L。除了 As 和 Mn，均在国家地表水标准范围内。在靠近温泉的湖的南侧，发现了相对较高的砷浓度，高达 116.2 µg/L。这项关于 Laguna de Bay 重金属当前水平的研究结果有助于评估和维持这个提供自然资源和生态系统服务的宝贵水生系统的污染预防策略。