A preliminary study of mercury exposure and blood pressure in the Brazilian Amazon.
BACKGROUND
Fish is considered protective for coronary heart disease (CHD), but mercury (Hg) intake from fish may counterbalance beneficial effects. Although neurotoxic effects of methylmercury (MeHg) are well established, cardiovascular effects are still debated. The objective of the present study was to evaluate blood pressure in relation to Hg exposure and fish consumption among a non-indigenous fish-eating population in the Brazilian Amazon.


METHODS
The study was conducted among 251 persons from six communities along the Tapajós River, a major tributary of the Amazon. Data was obtained for socio-demographic information, fish consumption, height and weight to determine body mass index (BMI), systolic and diastolic blood pressure, and Hg concentration in hair samples.


RESULTS
Results showed that overall, systolic and diastolic blood pressure, were relatively low (mean: 113.9 mmHg +/- 14.6 and 73.7 mmHg +/- 11.0). Blood pressure was significantly associated with hair total Hg (H-Hg), age, BMI and gender. No association was observed between fish consumption and blood pressure, although there were significant inter-community differences. Logistic regression analyses showed that the Odds Ratio (OR) for elevated systolic blood pressure (> or = 130 mmHg) with H-Hg > or = 10 microg/g was 2.91 [1.26-7.28], taking into account age, BMI, smoking, gender and community.


CONCLUSIONS
The findings of this preliminary study add further support for Hg cardiovascular toxicity.
Fillion
Myriam
M
Centre de recherche interdisciplinaire sur la biologie, la santé, la société et l'environnement (CINBIOSE), Université du Québec à Montréal, Succ. Centre-Ville, Montréal, Québec H3C 3P8, Canada. fillion.myriam@courrier.uqam.ca
Mergler
Donna
D
Sousa Passos
Carlos José
CJ
Larribe
Fabrice
F
Lemire
Mélanie
M
Guimarães
Jean Rémy Davée
JR
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D001794:Blood Pressure; D001938:Brazil / Q000453:epidemiology; D004032:Diet; D004781:Environmental Exposure; D005260:Female; D005399:Fishes; D005506:Food Contamination; D006801:Humans; D006973:Hypertension / Q000453:epidemiology / Q000209:etiology*; D008297:Male; D008628:Mercury / Q000009:adverse effects*; D008875:Middle Aged
D008628:Mercury