Estimating fish consumption rates for Ontario Amerindians

Area of Science:

• Environmental Health
• Toxicology
• Indigenous Health

Background:

• Human exposure to environmental contaminants often occurs through diet, particularly via consumption of fish which can bioaccumulate persistent chemicals.
• Assessing human exposure requires accurate data on dietary intake, especially for populations with high fish consumption rates.
• Freshwater fish are a significant dietary component for many communities, necessitating evaluation of contaminant exposure through this pathway.

Purpose of the Study:

• To estimate fish consumption rates among Ontario Amerindians.
• To identify factors influencing fish consumption patterns in this population.
• To provide data for improved risk assessment of contaminant exposure.

Main Methods:

• Utilized hair mercury concentrations from 4,327 Ontario Amerindians across 58 reserves.
• Combined hair mercury data with mercury concentrations in three commonly consumed fish species from surrounding lakes.
• Employed statistical analysis to estimate fish consumption rates and identify influencing factors.

Main Results:

• Estimated geometric mean fish consumption rates: 19 g/day for males and 14 g/day for females.
• Fish consumption increased with latitude (indicating community isolation) and age.
• Seasonal variations observed, with highest consumption in summer and lowest in winter.

Conclusions:

• Fish consumption rates vary significantly among Ontario Amerindians based on sex, age, geographic location, and season.
• These findings offer a more statistically representative basis for regulatory agencies to set fish consumption rate assumptions for risk assessments.
• Incorporating demographic and geographic factors is crucial for accurate contaminant exposure assessments.