Mercury Contamination within Protected Areas in the Brazilian Northern Amazon-Amapa State

Abstract

Mercury contamination is a long-standing environmental and social problem, notably in the Amazon. The widespread use of mercury in artisanal and small-scale gold mining has driven contamination of the environment and the people, threatening biodiversity, human health and livelihoods of traditional populations. Along the border area between Brazil and French Guiana, illegal gold mining is considered a critical threat to biodiversity, a social and economic problem and a political and diplomatic issue. On the Brazilian side in Amapá state, stands the world´s largest tropical forest National Park-Tumucumaque National Park (TNP). Despite its critical importance for the maintenance of ecosystem services, little is known about anthropic impacts in the area, including mercury contamination. The present study aims to assess the current levels of mercury contamination of carnivorous fish species in the TNP region as the starting point for the assessment of its impact over the integrity of protected areas and local communities. Fish samples were collected at 33 sampling sites within TNP and its surroundings. Samples of 187 most consumed local fish belonging to eight carnivore species were analyzed. Mercury was detected in 81% of the collected fish, the majority of them with individual levels above the WHO health safety limit (0.5 µg.g −1 ). Furthermore, samples from all rivers assessed presented some level of contamination. The contamination of important locally consumed fish is widespread in the study area. Important river basins in the Northern Amazon area are affected and even protected areas might be impacted by mercury. Our results suggest mercury as a significant threat to biodiversity and human health in the region. Additional studies should be conducted towards identifying the extent of the problem in the region and mitigation strategies addressing the effects of contamination must be incorporated in decision makers' priority agenda.

Mercury Exposure through Fish Consumption in Traditional Communities in the Brazilian Northern Amazon

“…The method includes four steps: (i) hazard identification, (ii) dose-response assessment, (iii) exposure assessment, and (iv) risk characterization. Most risk assessment studies use secondary data; however, our Hg exposure assessment used information on the most consumed fish species in the region [5] as well as informal interviews with local fishermen and individuals from indigenous and riverine communities.…”

“…Sampling sites were set up at potential ASGM sites (active and inactive). These sites were identified based on gold mining deforestation maps [3], literature reviews [5,17], the presence of local communities, the influence of coastal tides or inland waters, sampling logistics, the distance to protected areas, and interviews with managers of protected areas and locals with knowledge of the regional gold mining history. Sampling sites 1, 2, and 3 are directly influenced by coastal tides and are therefore considered coastal zones, while sites 4 and 5 are located in inland waters and are therefore referred to as inland zones.…”

“…ASGM is a major cause of deforestation and habitat degradation in the Brazilian northern Amazon [1][2][3], particularly on the borders between Guyana, French Guiana, Suriname, and Venezuela, and the Brazilian states of Roraima, Amapá, and Pará (also known as the Guiana Shield Ecoregion) [4]. The ecoregion covers 250 million hectares and contains one of the largest complexes of uninterrupted primary tropical forests on Earth [5]; the region therefore plays a critical role in mitigating global climate change and preserving biodiversity and freshwater ecosystems.…”

“…In this study, we aimed to develop a better understanding of the risks associated with fish consumption in various regions of the northern Amazon. Although a few studies have shown mercury contamination in fish in the region [5], this is the first to conduct an investigation on human Hg exposure in the study region. We assessed the potential toxicological health risks from mercury exposure through fish consumption for different age groups across five regions in Amapá State.…”

Community involvement works where enforcement fails: conservation success through community-based management of Amazon river turtle nests

“…Yet it is not possible to be certain whether this absence comes from historic overexploitation or biogeographic limits to the species distribution. Although surrounded by sustainable-use protected areas the continued survival of the traditional riverine communities is further complicated by mercury contamination of fish stocks ( Venturieri et al, 2017 ) and hydroelectric expansion ( Norris, Michalski & Gibbs, 2018 ) that degrade the natural resources upon which they depend.…”