, Volume 8, Issue 2, pp 210–222 | Cite as

Neurotoxic Sequelae of Mercury Exposure: An Intervention and Follow-up Study in the Brazilian Amazon

  • Myriam Fillion
  • Aline Philibert
  • Frédéric Mertens
  • Mélanie Lemire
  • Carlos José Sousa Passos
  • Benoit Frenette
  • Jean Rémy Davée Guimarães
  • Donna MerglerEmail author
Original Contribution


Since 1995, the Caruso Project used an Ecosystem Approach to Human Health to examine mercury (Hg) exposure in fish-eating communities in the Brazilian Amazon and develop interventions to maximise nutrition from traditional diet and minimise toxic risk. In 1995, 2000 and 2006, this study followed fish consumption, Hg levels, and visual and motor functions in 31 villagers. Questionnaires gathered information on socio-demographics and diet. Hair Hg (H-Hg) levels were measured. Visual acuity, colour vision, manual dexterity and grip strength were assessed. Data was analysed using general linear models of repeated measures. Total fish consumption, similar in 1995 and 2000, decreased in 2006. Carnivorous fish consumption initially decreased and then remained stable, whereas non-carnivorous fish consumption first increased and then decreased. H-Hg declined from 17.6 to 7.8 μg/g. Visual functions showed a significant decrease over time, with those with H-Hg ≥ 20 μg/g in 1995 showing greater loss. Motor functions showed initial improvement and then returned to the 1995 performance level. Decrease in Hg exposure is attributed to the intervention and socio-economic changes in the village. While there may be a certain reversibility of motor deficits, visual capacities may decrease progressively with respect to exposure prior to the intervention.


mercury fish consumption health Amazon intervention ecosystem approach 



We thank all the villagers that participated to this study, as well as the Brazilian field assistants. We are particularly grateful to the precious administrative work of Marie-Ève Thibault. We also thank the International Development Research Center (IDRC) and the Canadian Institutes of Health Research (CIHR) for their funding, and Health Canada for giving access to their laboratory facilities.


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Copyright information

© International Association for Ecology and Health 2011

Authors and Affiliations

  • Myriam Fillion
    • 1
  • Aline Philibert
    • 1
  • Frédéric Mertens
    • 2
  • Mélanie Lemire
    • 1
  • Carlos José Sousa Passos
    • 3
  • Benoit Frenette
    • 4
  • Jean Rémy Davée Guimarães
    • 5
  • Donna Mergler
    • 1
    Email author
  1. 1.Centre de recherche interdisciplinaire sur la biologie, la santé, la société et l’environnement (CINBIOSE)Université du Québec à MontréalMontrealCanada
  2. 2.Centro de Desenvolvimento Sustentável (CDS)Universidade de BrasíliaBrasíliaBrazil
  3. 3.Faculdade UnB PlanaltinaUniversidade de BrasíliaPlanaltinaBrazil
  4. 4.École d’optométrieUniversité de MontréalMontrealCanada
  5. 5.Laboratório de Traçadores, Instituto de BiofísicaUniversidade Federal do Rio de JaneiroRio de JaneiroBrazil

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