Dataset Information

Evidence of Mercury Methylation and Demethylation by the Estuarine Microbial Communities Obtained in Stable Hg Isotope Studies.

ABSTRACT: Microbial activity is a critical factor controlling methylmercury formation in aquatic environments. Microbial communities were isolated from sediments of two highly mercury-polluted areas of the Tagus Estuary (Barreiro and Cala do Norte) and differentiated according to their dependence on oxygen into three groups: aerobic, anaerobic, and sulphate-reducing microbial communities. Their potential to methylate mercury and demethylate methylmercury was evaluated through incubation with isotope-enriched Hg species (¹⁹⁹HgCl and CH?²⁰¹HgCl). The results showed that the isolated microbial communities are actively involved in methylation and demethylation processes. The production of CH?¹⁹⁹Hg was positively correlated with sulphate-reducing microbial communities, methylating up to 0.07% of the added ¹⁹⁹Hg within 48 h of incubation. A high rate of CH?²⁰¹Hg degradation was observed and >20% of CH?²⁰¹Hg was transformed. Mercury removal of inorganic forms was also observed. The results prove the simultaneous occurrence of microbial methylation and demethylation processes and indicate that microorganisms are mainly responsible for methylmercury formation and accumulation in the polluted Tagus Estuary.

SUBMITTER: Figueiredo N

PROVIDER: S-EPMC6210349 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature

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Evidence of Mercury Methylation and Demethylation by the Estuarine Microbial Communities Obtained in Stable Hg Isotope Studies.

Figueiredo Neusa N Serralheiro Maria Luísa ML Canário João J Duarte Aida A Hintelmann Holger H Carvalho Cristina C

International journal of environmental research and public health 20180929 10

Microbial activity is a critical factor controlling methylmercury formation in aquatic environments. Microbial communities were isolated from sediments of two highly mercury-polluted areas of the Tagus Estuary (Barreiro and Cala do Norte) and differentiated according to their dependence on oxygen into three groups: aerobic, anaerobic, and sulphate-reducing microbial communities. Their potential to methylate mercury and demethylate methylmercury was evaluated through incubation with isotope-enric ...[more]

PMID: 30274240

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Dataset Information

Evidence of Mercury Methylation and Demethylation by the Estuarine Microbial Communities Obtained in Stable Hg Isotope Studies.

Publications

Evidence of Mercury Methylation and Demethylation by the Estuarine Microbial Communities Obtained in Stable Hg Isotope Studies.

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