Exposure to Environmental Chemicals in Canada: Recent data from the Canadian Health Measures Survey

摘要

Canada monitors exposure to environmental chemicals as part of the Canadian Health Measures Survey (CHMS), a national direct measures health survey led by Statistics Canada, in partnership with Health Canada and the Public Health Agency of Canada. This national biomonitoring program provides levels of a range of environmental chemicals measured in blood, urine, or hair. This nationally-representative data provide a base to compare with sub-populations and with other countries. It is also the only baseline data for tracking trends in environmental chemical levels over time, and to explore relationships between exposure to environmental chemicals and other health measures (e.g., blood pressure, nutrition). The CHMS is a cross sectional survey carried out in ongoing two-year cycles. Every cycle, blood and urine are collected from around 5,000 participants aged 3-79 years at 16 sites across the country. Along with biomonitoring data, the CHMS also collects information on the general health and lifestyles of Canadians to provide information on chronic and infectious disease, physical fitness, nutrition, and other factors that influence health. Five cycles of data collection have been completed over the past decade, measuring over 250 chemicals (metals, persistent organic pollutants, environmental phenols, acrylamide, pesticides, phthalates) in over 30,000 Canadians at 81 sites across the country. For many chemicals, this data provides the first national level baseline of exposure. For others, repeated measures can help track exposure trends over time. Tools have also been developed to interpret and communicate biomonitoring data in a public health context. Biomonitoring equivalents (BEs) are risk-based tools used to derive hazard quotients to identify priority chemicals for further follow up. Arsenic is a case study that demonstrates how biomonitoring data helped prioritize chemicals for further analysis. Human biomonitoring data are used to quantify human exposure and to provide information for setting priorities to protect public health.