Long-Term Environmental Methylmercury Exposure Is Associated with Peripheral Neuropathy and Cognitive Impairment among an Amazon Indigenous Population
Widespread contamination of the Amazon basin with mercury has been reported to occur since at least the mid-80s due to heavy gold mining activity. Although initial studies have indicated that this may lead to deleterious neurological consequences to the indigenous populations living in the region, f...
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MDPI AG
2024-03-01
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| Series: | Toxics |
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| Online Access: | https://www.mdpi.com/2305-6304/12/3/212 |
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| author | Bruno H. Rebouças Gabriel T. Kubota Rogério A. A. Oliveira Bruna D. Pinto Roberta M. Cardoso Ana C. S. Vasconcellos Paulo C. Basta |
| author_facet | Bruno H. Rebouças Gabriel T. Kubota Rogério A. A. Oliveira Bruna D. Pinto Roberta M. Cardoso Ana C. S. Vasconcellos Paulo C. Basta |
| author_sort | Bruno H. Rebouças |
| collection | DOAJ |
| description | Widespread contamination of the Amazon basin with mercury has been reported to occur since at least the mid-80s due to heavy gold mining activity. Although initial studies have indicated that this may lead to deleterious neurological consequences to the indigenous populations living in the region, further research is needed to better characterize the neurological burden of such long-term exposure. With this aim, a cross-sectional exploratory study has been conducted with the Yanomami indigenous population residing in a northern Amazon region. All participants underwent a structured interview; detailed neurological examination, including assessment for cognitive, motor, coordination, and sensory functions; and laboratorial testing for serum hemoglobin, blood glucose, and methylmercury levels in hair samples. This study enrolled 154 individuals of 30.9 ± 16.8 years of age, of which 56.1% were female. Mean methylmercury levels in hair were 3.9 ± 1.7 µg/g. Methylmercury levels in hair > 6.0 µg/g were found in 10.3%. Among participants with hair methylmercury levels ≥ 6.0 μg/g, the prevalences of peripheral neuropathy and reduced cognitive performance were, respectively, 78.8% (95%CI 15–177%, <i>p</i> = 0.010) and 95.9% (95%CI 16–230.8%, <i>p</i> = 0.012) higher than those of individuals with lower levels. These results suggest that chronic mercury exposure may lead to significant and potentially irreversible neurotoxicity to Yanomami population living in the northern Amazon basin. |
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| language | English |
| last_indexed | 2024-04-24T17:47:11Z |
| publishDate | 2024-03-01 |
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| series | Toxics |
| spelling | doaj.art-591473622c1f4bbc9a891e1e3217e8a62024-03-27T14:06:15ZengMDPI AGToxics2305-63042024-03-0112321210.3390/toxics12030212Long-Term Environmental Methylmercury Exposure Is Associated with Peripheral Neuropathy and Cognitive Impairment among an Amazon Indigenous PopulationBruno H. Rebouças0Gabriel T. Kubota1Rogério A. A. Oliveira2Bruna D. Pinto3Roberta M. Cardoso4Ana C. S. Vasconcellos5Paulo C. Basta6Department of Neurology, Hospital das Clínicas, Faculty of Medicine, University of São Paulo (USP), Sao Paulo 05403-000, BrazilDepartment of Neurology, Hospital das Clínicas, Faculty of Medicine, University of São Paulo (USP), Sao Paulo 05403-000, BrazilDepartment of Neurology, Hospital das Clínicas, Faculty of Medicine, University of São Paulo (USP), Sao Paulo 05403-000, BrazilDepartment of Neurology, Hospital das Clínicas, Faculty of Medicine, University of São Paulo (USP), Sao Paulo 05403-000, BrazilDepartment of Neurology, Hospital das Clínicas, Faculty of Medicine, University of São Paulo (USP), Sao Paulo 05403-000, BrazilLaboratory of Professional Education in Health Surveillance, Polytechnic School of Health Joaquim Venacio (EPSJV), Oswald Cruz Foundation (Fiocruz), Rio de Janeiro 21040-900, BrazilProgram of Post-Graduation in Public Health and Environment, National School of Public Health (ENSP), Oswald Cruz Foundation (Fiocruz), Rio de Janeiro 21040-900, BrazilWidespread contamination of the Amazon basin with mercury has been reported to occur since at least the mid-80s due to heavy gold mining activity. Although initial studies have indicated that this may lead to deleterious neurological consequences to the indigenous populations living in the region, further research is needed to better characterize the neurological burden of such long-term exposure. With this aim, a cross-sectional exploratory study has been conducted with the Yanomami indigenous population residing in a northern Amazon region. All participants underwent a structured interview; detailed neurological examination, including assessment for cognitive, motor, coordination, and sensory functions; and laboratorial testing for serum hemoglobin, blood glucose, and methylmercury levels in hair samples. This study enrolled 154 individuals of 30.9 ± 16.8 years of age, of which 56.1% were female. Mean methylmercury levels in hair were 3.9 ± 1.7 µg/g. Methylmercury levels in hair > 6.0 µg/g were found in 10.3%. Among participants with hair methylmercury levels ≥ 6.0 μg/g, the prevalences of peripheral neuropathy and reduced cognitive performance were, respectively, 78.8% (95%CI 15–177%, <i>p</i> = 0.010) and 95.9% (95%CI 16–230.8%, <i>p</i> = 0.012) higher than those of individuals with lower levels. These results suggest that chronic mercury exposure may lead to significant and potentially irreversible neurotoxicity to Yanomami population living in the northern Amazon basin.https://www.mdpi.com/2305-6304/12/3/212mercury poisoningneurotoxicity syndromesindigenous peoplescognitive dysfunctionmethylmercury compoundspolyneuropathy |
| spellingShingle | Bruno H. Rebouças Gabriel T. Kubota Rogério A. A. Oliveira Bruna D. Pinto Roberta M. Cardoso Ana C. S. Vasconcellos Paulo C. Basta Long-Term Environmental Methylmercury Exposure Is Associated with Peripheral Neuropathy and Cognitive Impairment among an Amazon Indigenous Population Toxics mercury poisoning neurotoxicity syndromes indigenous peoples cognitive dysfunction methylmercury compounds polyneuropathy |
| title | Long-Term Environmental Methylmercury Exposure Is Associated with Peripheral Neuropathy and Cognitive Impairment among an Amazon Indigenous Population |
| title_full | Long-Term Environmental Methylmercury Exposure Is Associated with Peripheral Neuropathy and Cognitive Impairment among an Amazon Indigenous Population |
| title_fullStr | Long-Term Environmental Methylmercury Exposure Is Associated with Peripheral Neuropathy and Cognitive Impairment among an Amazon Indigenous Population |
| title_full_unstemmed | Long-Term Environmental Methylmercury Exposure Is Associated with Peripheral Neuropathy and Cognitive Impairment among an Amazon Indigenous Population |
| title_short | Long-Term Environmental Methylmercury Exposure Is Associated with Peripheral Neuropathy and Cognitive Impairment among an Amazon Indigenous Population |
| title_sort | long term environmental methylmercury exposure is associated with peripheral neuropathy and cognitive impairment among an amazon indigenous population |
| topic | mercury poisoning neurotoxicity syndromes indigenous peoples cognitive dysfunction methylmercury compounds polyneuropathy |
| url | https://www.mdpi.com/2305-6304/12/3/212 |
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