by Tracey Bushnik, Douglas Haines, Patrick Levallois, Johanne Levesque, Jay Van Oostdam and Claude Viau
Lead is a known toxicant that occurs naturally in the environment. Bisphenol A (BPA) is an industrial chemical used primarily in polycarbonate plastic and epoxy resins. It has been 30 years since lead exposure was measured at a national level, and it is the first time for a national assessment of BPA exposure.
Data are from the 2007-2009 Canadian Health Measure Survey. Lead in whole blood (PbB) and urinary BPA were measured in 5,319 and 5,476 respondents aged 6 to 79, respectively. Geometric means (GMs) are presented by age group and sex for PbB (µg/dL), volume-based BPA (µg/L), and creatinine-standardized BPA (µg/g creatinine). Adjusted least squares geometric means (LSGMs) for PbB and BPA are presented by selected covariates.
PbB was detected in 100% of the population, with a GM concentration of 1.34 μg/dL. Adults aged 60 to 79 and males had significantly higher GM PbB concentrations. Lower household income, being born outside Canada, living in a dwelling at least 50 years old, current or former smoking, and drinking alcohol at least once a week were associated with higher PbB concentrations. Urinary BPA was detected in 91% of the population, with a GM concentration of 1.16 μg/L (1.40 μg/g creatinine). Children aged 6 to 11 had significantly higher GM creatinine-standardized BPA concentrations than did other age groups.
Although PbB concentrations have declined dramatically since the 1970s, socio-demographic characteristics, the age of dwellings, and certain lifestyle behaviours are associated with higher levels. Given the short half-life of orally ingested BPA and the high frequency of detection, the CHMS data suggest continual widespread exposure in the Canadian population.
biomonitoring, blood lead, detection, environmental exposure
Every day, people are exposed to natural and manmade chemicals―in the air, food and water, and consumer products. These chemicals can enter the body through ingestion, inhalation, and/or dermal contact. They may be essential nutrients or toxic compounds. Human biomonitoring is an effective way to provide baseline information about levels of exposure to environmental chemicals, and can help determine usual exposure and changes over time. It involves the direct measurement of chemicals or their metabolites in blood, urine, other bodily fluids or tissues. From March 2007 through February 2009, the Canadian Health Measures Survey (CHMS) collected biomonitoring data from a nationally representative sample of the population.[Full text]
Tracey Bushnik (1-613-951-2301; Tracey.Bushnik@statcan.gc.ca) is with the Health Analysis Division and Johanne Levesque is with the Physical Health Measures Division at Statistics Canada, Ottawa, Ontario K1A 0T6. Douglas Haines and Jay Van Oostdam are with Health Canada. Patrick Levallois is with l’Institut national de santé publique du Québec. Claude Viau is with the University of Montreal.