High methylmercury uptake by green algae in Lake Titicaca: Potential implications for remediation

Forskningsoutput: TidskriftsbidragArtikel i vetenskaplig tidskrift

Abstract

Anthropogenic pressure in the high altitude lakes such as Titicaca and Uru (Bolivia) may favor the production of methylmercury (MeHg) known to accumulate in trophic chains. Periphyton associated with emerged aquatic plants (totoras) from the lake shores accumulates and demethylates MeHg providing a potential cost-effective water treatment technique. In this laboratory study, we measured the MeHg uptake kinetics of a consortium of green algae isolated from Lake Titicaca totora's periphyton. The most abundant algal consortium, composed of Oedogonium spp., Chlorella spp., Scenedesmus spp., was exposed to rising MeHg concentrations (from 5 to 200 ng·L−1) to assess their maximum potential capacity for MeHg accumulation. Various algal biomass concentrations were tested to choose the optimal one. Results provided a net MeHg uptake rate by this algal consortium of 2.38 amol ng−1·h−1·nM−1 (the total uptake was 2863 ng MeHg·g−1) for an initial concentration of 200 ng MeHg·L−1 with an algal biomass concentration of 0.02 g·L−1. This initial MeHg concentration is 1000 times higher than the one measured in the eutrophic Cohana Bay of Lake Titicaca, which shows the high accumulation potential of these green algae. Our data suggest that periphyton has a high potential for the treatment of Hg contaminated waters in constructing wetlands in the Andean Altiplano.

Detaljer

Författare
  • Roxana Quiroga-Flores
  • Stéphane Guédron
  • Dario Achá
Enheter & grupper
Externa organisationer
  • Higher University of San Andrés
  • University Grenoble Alpes
Forskningsområden

Ämnesklassifikation (UKÄ) – OBLIGATORISK

  • Vattenbehandling

Nyckelord

Originalspråkengelska
Artikelnummer111256
TidskriftEcotoxicology and Environmental Safety
Volym207
StatusPublished - 2021 jan 1
PublikationskategoriForskning
Peer review utfördJa