Persistent organic pollutants (POPs) and metals in primiparous women: a comparison from Canada and Mexico.

Under the North American Commission for Environmental Cooperation (CEC) and its Sound Management of Chemicals (SMOC) program, a tri-national human contaminant monitoring initiative was completed to provide baseline exposure information for several environmental contaminants in Canada, Mexico and the United States (U.S). Blood samples were collected from primiparous women in Canada and Mexico, and were analysed for a suite of environmental contaminants including polychlorinated biphenyls (PCBs), dichlorodiphenyldichloroethylene(p,p'-DDE),beta-hexachlorocyclohexane (β-HCH), mercury and lead.

Sampling criteria for identifying human biomonitoring chemical differences in the Canadian Arctic.

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.

Comparing plasma concentrations of persistent organic pollutants and metals in primiparous women from northern and southern Canada.

The exposure of Aboriginal peoples in the Canadian Arctic to persistent organic pollutants (POPs) and metals through the consumption of traditional food items is well recognized; however, less information is available for Canadian immigrants. The direct comparison of blood chemical concentrations for expectant primiparous women sampled in the Inuvik and Baffin regions of the Canadian Arctic, as well as Canadian- and foreign-born women from five southern Canadian centers (Halifax, Vancouver, Hamilton, Ottawa, and Calgary), provides relative exposure information for samples of northern and southern mothers in Canada. Based on our analyses, Canadian mothers are exposed to a similar suite of contaminants; however, Inuit first birth mothers residing in the Canadian Arctic had higher age-adjusted geometric mean concentrations for several legacy POPs regulated under the Stockholm Convention, along with lead and total mercury.

Brominated flame retardant concentrations in sera from the Canadian Health Measures Survey (CHMS) from 2007 to 2009.

Pooling of surplus serum from individual samples, collected between 2007 and 2009 during Cycle 1 of the Canadian Health Measures Survey (CHMS), was performed to develop a national baseline estimate of brominated flame retardants in Canadians. Serum samples were categorized by sex and distributed by five age groups ranging from 6 to 79years. Nearly 5000 (4583) serum samples were used to form 59 composite pools.

Circulating metals and persistent organic pollutant concentrations in Canadian and non-Canadian born primiparous women from five Canadian centres: results of a pilot biomonitoring study.

The developing foetus is thought to be at increased risk from exposure to environmental contaminants; however, developmental exposure data is notably lacking for many contaminants. Moreover, potential regional differences or effect of place of birth on residue levels measured in pregnant women is also unknown. Therefore, as part of a multinational biomonitoring study, 125 primiparous pregnant Canadian women were recruited from five Canadian centres (Vancouver, Calgary, Hamilton, Ottawa, and Halifax).

PCDD/F and PCB concentrations in sera from the Canadian Health Measures Survey (CHMS) from 2007 to 2009.

In order to establish a national baseline estimate of the concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and polychlorinated biphenyls (PCBs) in Canadians, pooling of individual human sera was performed to ensure that a high frequency of detectable concentrations of analytes would be achieved. Nearly 5000 (4583) sera samples from Cycle 1 of the Canadian Health Measures Survey (CHMS) collected between 2007 and 2009 were used to form 59 composite pools of approximately 25 mL each. Pools were categorized by sex and age with participants ranging from 6 to 79 years.

Persistent organic pollutant concentrations in first birth mothers across Mexico.

This project was initiated by the North America Commission for Environmental Cooperation (CEC). Its main purpose was to obtain an initial profile on pregnant woman's exposure to persistent organic pollutants (POPs) in North America (Canada, the United States and Mexico). Persistent organic pollutants are transferred to the fetus via the placenta during the pregnancy or to the infant via maternal milk; therefore, the pregnant woman's body burden is important because of the higher exposures and potential health effects in the fetus and infant.

Lead and bisphenol A concentrations in the Canadian population.

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.

Environmental contaminants and human health in the Canadian Arctic.

The third Canadian Arctic Human Health Assessment conducted under the Canadian Northern Contaminants Program (NCP), in association with the circumpolar Arctic Monitoring and Assessment Programme (AMAP), addresses concerns about possible adverse health effects in individuals exposed to environmental contaminants through a diet containing country foods. The objectives here are to: 1) provide data on changes in human contaminant concentrations and exposure among Canadian Arctic peoples; 2) identify new contaminants of concern; 3) discuss possible health effects; 4) outline risk communication about contaminants in country food; and 5) identify knowledge gaps for future contaminant research and monitoring. The nutritional and cultural benefits of country foods are substantial; however, some dietary studies suggest declines in the amount of country foods being consumed.

Human health implications of environmental contaminants in Arctic Canada: A review.

The objectives of this paper are to: assess the impact of exposure to current levels of environmental contaminants in the Canadian Arctic on human health; identify the data and knowledge gaps that need to be filled by future human health research and monitoring; examine how these issues have changed since our first assessment [Van Oostdam, J., Gilman, A., Dewailly, E.

Contaminants in Canadian arctic biota and implications for human health: conclusions and knowledge gaps.

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.

Maternal and umbilical cord blood levels of mercury, lead, cadmium, and essential trace elements in Arctic Canada.

Maternal and umbilical cord blood levels of mercury (Hg), lead (Pb), cadmium (Cd), and the trace elements copper (Cu), zinc (Zn), and selenium (Se) are reported for Inuit, Dene/Métis, Caucasian, and Other nonaboriginal participants from Arctic Canada. This is the first human tissue monitoring program covering the entire Northwest Territories and Nunavut for multiple contaminants and establishes a baseline upon which future comparisons can be made. Results for chlorinated organic pesticides and PCBs for these participants have been reported elsewhere.

Circumpolar maternal blood contaminant survey, 1994-1997 organochlorine compounds.

During the past 20 years a number of studies have found neurological and immunological effects in the developing fetus and infants exposed to background or only slightly elevated levels of persistent organic pollutants (POPs) such as polychlorinated biphenyls (PCBs). To address concerns arising from possible increased human exposure in the Arctic and possible effects of POPs, all circumpolar countries agreed in 1994 to monitoring of specific human tissues for contaminants in the Arctic under the Arctic Monitoring and Assessment Program (AMAP). Mothers in eight circumpolar countries contributed blood samples that were analysed at a single laboratory for 14 PCB congeners (IUPAC No.

Organochlorine levels in maternal and umbilical cord blood plasma in Arctic Canada.

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, Métis, 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.

Human health implications of environmental contaminants in Arctic Canada: a review.

This paper assesses the impact on human health of exposure to current levels of environmental contaminants in the Canadian Arctic, and identifies the data gaps that need to be filled by future human health research and monitoring. The concept of health in indigenous groups of the Arctic includes social, cultural, and spiritual dimensions. The harvesting, sharing and consumption of traditional foods are an integral component to good health among Aboriginal people influencing both physical health and social well-being.

Concentrations of organochlorine pesticides in the adipose tissue of British Columbia residents.

Adipose tissue from a sample of 41 British Columbians was analyzed for a number of organochlorine pesticides. Pesticide concentrations were very low. Persistent fat-soluble compounds like DDT were found at the highest concentrations, whereas compounds that either quickly metabolize to other forms or are readily excreted were found at low levels or not detected.

Canadian perspectives on aluminum.

The multi-media approach to aluminum exposure will allow a more informed decision on the inclusion or exclusion of various exposure media in future epidemiological studies.Knowledge of the types of Al (speciation) and their respective bioavailability will enable interpretation of the importance of specific media.

Effect of urethan anesthesia on cigarette smoke-induced airway injury in guinea pigs.

The effect of urethan anesthesia on cigarette smoke-induced airway responsiveness and permeability was studied in the guinea pig. Airway responsiveness was determined by measuring changes to airway resistance to graded doses of aerosolized histamine, and mucosal permeability was determined by measuring the appearance of fluorescein isothiocyanate-dextran (FITC-D) in the blood and examining its distribution in lung tissue after it had been delivered to the lung in an aerosol. The results confirm previous studies that smoke exposure increased airway responsiveness and mucosal permeability.

A rabbit model of hypersensitivity to plicatic acid, the agent responsible for red cedar asthma.

We describe a rabbit model for the study of the immunogenicity and allergenicity of plicatic acid (PA), the small molecular weight compound in western red cedar responsible for occupational asthma in exposed workers. Specific anti-PA IgE as well as IgG antibodies could be raised, depending on the method of immunization. The sensitized rabbits reacted to antigenic challenge with PA-protein conjugates intravenously, with increases in respiratory frequency and pulmonary resistance.

Effect of breathing dry air on structure and function of airways.

We compared the effect of breathing dry air (0.70 mg H2O/l) with that of breathing room air (8.62 mg H2O/l) in guinea pigs anesthetized with urethane.