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Background 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 and methods 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. Results 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. Interpretation 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. [ABSTRACT FROM AUTHOR]

Human biomonitoring studies in the Canadian Arctic have measured a wide range of metals and persistent organic pollutants in Aboriginal and non-Aboriginal mothers during two time periods in the Northwest Territories and Nunavut. This analysis provides preliminary estimates on sample sizes and sampling frequencies required to measure significant changes in maternal blood concentrations for PCB 153 and total mercury. For example, sample sizes of 35-40 mothers permit the detection of a 40% decrease in these chemical concentrations between two groups (e.g. communities or regions). Improvements in method sensitivity can be achieved by on-going sampling over multiple time periods (e.g. 4 or 5) in these regions, or increasing sample sizes. [ABSTRACT FROM AUTHOR]

A baseline for exposure to organochlorine and metal contaminants has been established for mothers and newborns in the Northwest Territories and Nunavut areas of Arctic Canada. Maternal and umbilical cord blood plasma organochlorine levels are described for Inuit, Dene, Me´tis, Caucasian and Other non-Aboriginal participants. Overall, 523 women volunteered to participate by giving their written informed consent between May 1994 and June 1999, resulting in the collection of 386 maternal blood samples, 407 cord blood samples and 351 maternal/cord pairs. Nearly half of all the participants regularly smoked cigarettes, including 77% of the Inuit participants. Maternal and cord results are presented for PCBs (as Aroclor 1260 and 14 congeners) and organochlorine pesticides, including p,p′-DDT, p,p′-DDE, beta-hexachlorocyclohexane (β-HCH), hexachlorobenzene (HCB), cis and trans nonachlor, heptachlor epoxide, oxychlordane, mirex, dieldrin and toxaphene. Maternal PCB levels (as Aroclor 1260) averaged 4.42 (±9.03) μg/l in Inuit, which was 3.3 times higher than those found in Dene/Me´tis, and 3.4 times higher than levels in Caucasians. Mean DDE levels were 2.8 times higher in the Other non-Aboriginal group (Chinese, Filipino, East Indian and multiple ethnicity) than in the Inuit group, at 3.99 μg/l and 1.42 μg/l, respectively. Cord blood PCB levels (as Aroclor 1260) averaged 1.16 (±2.42) μg/l for Inuit participants, which was 3.3–4 fold higher than the other ethnic groups. PCBs, p,p′-DDE and hexachlorobenzene were detected in all maternal samples, and p,p′-DDE was detected in all cord samples. Regression coefficients for maternal/cord pairs are presented for selected organochlorines. Other results from this study, including maternal and cord metals data, will be presented elsewhere. [Copyright &y& Elsevier]

This paper summarizes the major findings of the special issue entitled "Contaminants in Canadian Arctic Biota and Implications for Human Health." The individual papers and reviews in this special issue present a large amount of new information on contaminants in biota primarily from the Canadian arctic as well as from Alaska, Greenland and the European Arctic. Temporal and spatial trends are examined and potential biological effects on wildlife are assessed. The special issue also presents new and updated data on human exposure to and possible health effects of current levels of environmental contaminants in the Canadian Arctic. As part of the assessment of the human health implications, the unique structures and processes that have developed in the Canadian Arctic under the Northern Contaminants Program (NCP) of Indian and Northern Affairs Canada to build partnerships and manage and communicate the benefits and risks associated with contaminant exposure are discussed. Application of this information in international forums to reduce anthropogenic emissions of contaminants to the environment is also discussed.