Abstract
Heavy metals can come from both natural and anthropogenic sources. These substances are non-biodegradable and bioaccumulative. With this, their presence in the environment poses both non-carcinogenic and carcinogenic health risks to surrounding communities, as these substances can enter the body through the oral or dermal routes of exposure. This study determined whether the hazard quotients calculated from actual lead and cadmium concentrations exceed those calculated from DENR standards. Following this, a policy brief was drafted based on the findings of the study. This study was conducted through a systematic review and meta-analysis of published studies from various research databases. The conducted meta-analysis indicates overall effect sizes of 9.29 for cadmium and 3.20 for lead, suggesting an excess of allowable heavy metal concentrations in the identified bodies of water in the Philippines. It was also determined through human health risk assessment calculations that the majority of hazard quotients and incremental lifetime cancer risk values have exceeded accepted standards, indicating possible harm to surrounding communities. Finally, the formulated policy brief focuses on community participation and engagement, improvements to waste treatment facilities, the implementation of advanced monitoring systems, and the formulation of improved programs to enhance the management of heavy metals in the environment.
