Total Mercury Content in the Tissues of Freshwater Chelonium (Podocnemis expansa) and a Human Health Risk Assessment for the Amazon Population in Brazil

Fábio Júnior Targino; Joanna Damazio de Nunes Ribeiro; Julia Siqueira Simões; Carla Silva Carneiro; Stella Maris Lazzarini; Aline Ramos Souza; Micheli da Silva Ferreira; Sergio Borges Mano; Eliane Teixeira Mársico

doi:10.3390/ijerph20156489

Total Mercury Content in the Tissues of Freshwater Chelonium (Podocnemis expansa) and a Human Health Risk Assessment for the Amazon Population in Brazil

Int J Environ Res Public Health. 2023 Aug 1;20(15):6489. doi: 10.3390/ijerph20156489.

Authors

Fábio Júnior Targino¹, Joanna Damazio de Nunes Ribeiro¹, Julia Siqueira Simões¹, Carla Silva Carneiro², Stella Maris Lazzarini³, Aline Ramos Souza^{3

4}, Micheli da Silva Ferreira¹, Sergio Borges Mano¹, Eliane Teixeira Mársico¹

Affiliations

¹ Faculty of Veterinary, Universidade Federal Fluminense (UFF), Niterói 24230-321, Brazil.
² Faculty of Pharmacy, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro 21941-580, Brazil.
³ Centro de Pesquisa e Preservação de Mamíferos Aquáticos (CPPMA), Eletronorte, Presidente Figueiredo 69736-000, Brazil.
⁴ Institute of Biological Sciences, Universidade Federal do Amazonas (UFAM), Manaus 69077-000, Brazil.

Abstract

Researchers recognize the silent, negative and deleterious effects caused by mercury pollution in gold mining areas. Freshwater turtles are culturally part of the diet of riverside populations in the Amazon region and this area presents mercury (Hg) pollution issues mainly due to gold mining activities. Thus, this research aimed to evaluate the total mercury (THg) content in the different organs of Amazonian giant river turtle (Podocnemis expansa) and carry out a human health risk assessment associated with the consumption of these animals. This study was conducted in the Vila Balbina, municipality of Presidente Figueiredo, state of Amazonas, Brazil. Skin (n = 28), muscle (n = 19) and brain (n = 2) samples were analyzed by Atomic Absorption Spectrometry (TDA-AAS) and a DMA-80™ mercury analyzer was used for the total mercury determinations. The average values found for THg in the skin, muscle and brain samples were, respectively, 0.1045 mg·kg^-1, 0.1092 mg·kg^-1 and 0.0601 mg·kg^-1. Thus, THg was observed even though the P. expansa were kept in captivity, possibly due to previous contamination by air, water and food. The Hazard Quotient (HQ) was calculated considering a 9.07 g·day^-1 intake dose of P. expansa and the consumption of turtles once a week showed an HQ = 2.45, which may cause long-term injuries to human health. Although the muscle concentrations were below the maximum limit established by the World Health Organization (WHO) and Brazilian regulatory agencies, it is important to evaluate consumption factors such as amount ingested, frequency and animal gender, which may cause a potential risk to regular consumers due to mercury bioaccumulation. The WHO may consider various aspects in order to warn the Amazon population about the severity and silent hazard of this metal, especially due to the importance of this matrix in the region. This region urgently needs government actions to inhibit clandestine mining and to prevent future serious, chronic health problems of the entire population.

Keywords: biomonitoring; environmental pollution; food safety; freshwater toxicology; public health; trace elements.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Brazil
Environmental Monitoring / methods
Fishes
Fresh Water
Gold
Humans
Mercury* / analysis
Risk Assessment
Turtles*
Water Pollutants, Chemical* / analysis

Substances

Mercury
Gold
Water Pollutants, Chemical

Grants and funding

This research was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior—Brazil (CAPES) (financing code 001), Brazil and by the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPQ), Brazil (Grant number 311974/2019–8).