Safe concentration of mercury (Hg) exposure in fish consumed by the residents of Bulawa Subdistrict, Bone Bolango District, Gorontalo Province, Indonesia

Mercury is one of the persistent chemicals and is bioaccumulative in the ecosystem. It negatively affects human health and environment. Indonesia has been identified in the use of mercury in industrial sector, especially small industries. High level of mercury needs to be reduced and eliminated. The present study aims to determine the safe concentration of mercury that has negative impact on health of the community of Bulawa Sub-district, Bone Bolango District, Gorontalo. The approach taken in this study was cross sectional with observational research. In the present study, the population was all residents of Bulawa Subdistrict, Bone Bolango District, Gorontalo who were exposed to mercury from fish. The sample in this study was 100 residents who consumed fish caught in Bulawa waters. Sampling was carried out by purposive sampling. Data analysis performed in manual quantitative data analysis to determine the safe (C safe) concentration of mercury for workers. Experimental data includes white rats (W animals), body surface area of white mice (BSA animals), body weight (W), workers’ height (h), workers’ respiratory rate (BR), workers’ body surface area (BSA), working time (t), mercury concentration (C), NOAEL, animal km, human km, and safe limits for toxin doses (RfD). The results showed that the measurement of mercury concentration in Bulawa District, Bone Bolango District, Gorontalo was 0.128 mg/m³ (0.0156 ppm). This value can be used as a reference limit for safe concentration of mercury in the residents who consume fish originating from the waters of traditional mining areas in Indonesia. Control efforts can be created by reducing mercury concentrations in fish, or reducing the rate of fish consumption and limiting the duration of exposure.