ABSTRACT
Mercury is one of the most dangerous contaminants on the planet. In recent years, evidence of mercury contamination in the Amazon has significantly increased, notably due to gold-mining activities. Although mercury contamination in fish has consistently been documented, little is known about the risk associated with fish consumption by populations in urban areas of the Amazon. We sampled 1010 fish sold in public markets in six state capitals and 11 additional cities. Mercury levels were determined for each specimen, and the evaluation of the health risks associated with consuming mercury-contaminated fish was conducted according to the methodology proposed by the World Health Organization (WHO). Our study reveals that more than one-fifth (21.3%) of the fish sold in urban centers had mercury levels above the safe limits (≥0.5 µg/g) established by the Brazilian Health Surveillance Agency (ANVISA). The prevalence of Hg contamination ≥0.5 µg/g was approximately 14 times higher in carnivorous than in noncarnivorous fish. The analysis of the risk attributable to fish consumption reveals that daily mercury intake exceeded the reference dose recommended by the U.S. EPA in all population groups analyzed, reaching up to 7 and 31 times in women of childbearing age and children from 2 to 4 years old, respectively. However, these risks are diverse depending on the type of fish consumed and must be considered to formulate appropriate nutritional guidelines for safe fish consumption by the local community.
ABSTRACT
Artisanal small-scale gold mining (ASGM) is the main source of anthropogenic mercury emissions and contamination in Latin America. In the Brazilian northern Amazon, ASGM has contaminated the environment and people over the past century. The main contamination route is through fish consumption, which endangers the food security and livelihoods of traditional communities. Our study aims to assess the potential toxicological health risks caused by the consumption of Hg-contaminated fish across five regions in Amapá State. We sampled 428 fish from 18 sites across inland and coastal aquatic systems. We measured the total mercury content in fish samples, and the results were applied to a mercury exposure risk assessment targeting three distinct groups (adults, women of childbearing age, and children). Mercury contamination was found to exceed the World Health Organization's safe limit in 28.7% of all fish samples, with higher prevalence in inland zones. Moreover, the local preference for carnivorous fish species presents a serious health risk, particularly for communities near inland rivers in the region. This is the first study to provide clear recommendations for reducing the mercury exposure through fish consumption in Amapá State. It builds scientific evidence that helps decision-makers to implement effective policies for protecting the health of riverine communities.
