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Nationally representative human biomonitoring data on persistent organic pollutants (POPs) including organochlorine pesticides (OCs), polychlorinated biphenyls (PCBs) brominated flame retardants (BFRs) and perfluoroalkyl substances (PFASs) are available through the Canadian Health Measures Survey (CHMS). We have used a systematic approach building on the reference interval concept proposed by the International Federation of Clinical Chemistry and Laboratory Medicine and the International Union of Pure and Applied Chemistry to derive human biomonitoring reference values (RV 95 s) for selected POPs in blood plasma in the general Canadian population. Biomarkers were chosen based on specific selection criteria including their detection in most Canadians (>66% detection rate). Age and sex were evaluated as possible partitioning criteria and separate RV 95 s were derived for the sub-populations in cases where partitioning was deemed necessary. RV 95 s for OCs, PCBs, and BFRs were derived both on a whole weight of blood plasma and on a lipid weight adjusted basis whereas they were derived only on a whole weight basis for PFASs. RV 95 s ranged from 0.018μg/L (PCB 201) to 21μg/L (perfluorooctane sulfonate) and from 3.1μg/kg lipid (PCB 201) to 1400μg/kg lipid (p,p'-DDE). The 22 RV 95 s reported in this paper represent the first set of reference values for POPs in the Canadian general population against which individual and population human biomonitoring data may be compared., (Crown Copyright © 2017. Published by Elsevier GmbH. All rights reserved.)

Human biomonitoring (HBM) is used to indicate and quantify exposure by measuring environmental chemicals, their metabolites or reaction products in biological specimens. The biomonitoring component of the Canadian Health Measures Survey (CHMS) is the most comprehensive initiative providing general population HBM data in Canada. The CHMS is an ongoing cross-sectional direct measures survey implemented in 2-year cycles. It provides nationally-representative data on health, nutritional status, environmental exposures, and related risks and protective characteristics. The survey follows a robust planning, design and sampling protocol as well as a comprehensive quality assurance and quality control regime implemented for all aspect of the survey to ensure the validity of the HBM results. HBM blood and urine data are available for CHMS cycles 1 (2007-2009), 2 (2009-2011) and 3 (2012-2013). Field collection has been completed for cycle 4 (2014-2015), with cycle 5 (2016-2017) in progress and cycle 6 planning (2018-2019) being finalized. Biomonitoring results for 279 chemicals are expected over the six cycles of the CHMS (220 in individual blood, urine or hair samples, and 59 in pooled serum samples). The chemicals include metals and trace elements, polychlorinated biphenyls (PCBs), organochlorines, flame retardants, perfluoroalkyl substances, volatile organic compounds (VOCs) and metabolites, environmental phenols, triclocarban, acrylamide, pesticides (e.g., triazines, carbamates, organophosphates, phenoxy, pyrethroids) and/or their metabolites, chlorophenols, polycyclic aromatic hydrocarbon (PAH) metabolites, phthalates and alternate plasticizer metabolites, and tobacco biomarkers. Approximately one half of the chemicals measured in individual blood and urine samples over the first three cycles were detected in more than 60% of samples. CHMS biomonitoring data have been used to establish baseline HBM concentrations in Canadians; inform public health, regulatory risk assessment and management decisions; and fulfil national and international reporting requirements. Concurrent efforts are underway in Canada to develop statistically- and risk-based concepts and tools to interpret biomonitoring data., (Crown Copyright © 2016. Published by Elsevier GmbH. All rights reserved.)

Background: Perfluorinated compounds (PFCs) are man-made chemicals that are heat stable, non-flammable and able to repel both water and oils. Biomonitoring research shows global distribution in human, animal and aquatic environments of these chemicals. PFCs have been shown to activate the peroxisome proliferator-activated receptors which play a large role in metabolism and the regulation of energy homeostasis. Previous epidemiological research has also suggested a potential role of PFCs on lipid and glucose metabolism., Objectives: The objectives of this study were to examine the association between the levels of perfluorinated compounds perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), and perfluorohexane sulfonate (PFHxS) in plasma and metabolic function and plasma lipid levels., Methods: Using cross-sectional data from the Canadian Health Measures Survey (Cycle 1 2007-2009) we examined the association in adults between plasma levels of PFOA, PFOS and PFHxS (n=2700) on cholesterol outcomes, metabolic syndrome and glucose homeostasis using multivariate linear and logistic regression models., Results: We found some evidence of a significant association between perfluoroalkyl substances, notably PFHxS, with total cholesterol (TC), low-density lipoprotein cholesterol (LDL), total cholesterol/high density lipoprotein cholesterol ratio (TC/HDL) and non-HDL cholesterol as well as an elevated odds of high cholesterol. We found some associations with PFOA and PFOS in our unweighted models but these results did not remain significant after weighting for sampling strategy. We found no association with metabolic syndrome, or glucose homeostasis parameters., Conclusions: This study showed lower levels of PFOA and PFOS and slightly higher levels of PFHxS than other published population studies. Our results did not give significant evidence to support the association with cholesterol outcomes with PFOS and PFOA. However, we did observe several significant associations with the PFHxS and cholesterol outcomes (LDL, TC, NON-HDL, TC/HDL ratio)., (Crown Copyright © 2012. Published by Elsevier Inc. All rights reserved.)

Biomonitoring is used increasingly as an indicator and quantitative measure of exposure; however, there is a large gap in interpreting and communicating biomonitoring results to study participants. Two separate, national biomonitoring initiatives are under way in Canada; the household recruitment-based Canadian Health Measures Survey (CHMS) and the clinic recruitment-based Maternal-Infant Research on Environmental Chemicals (MIREC) Study. The CHMS provides participants with the option to receive all their results, but this option is not provided to MIREC participants. The approach to reporting results to participants depends on the availability of reference ranges and guidelines for which tissue concentrations may be interpreted as being elevated or associated with increased health risks, how participants are recruited, unique vulnerabilities of the population, legislation governing access to personal information, and decisions of research ethics committees. It is the researchers' responsibility to present the best case for their approach and, once the decision has been made, to inform participants about access to their results through the consent process.

Background: Early diagnosis during newborn screening or infancy has enabled the observation of the natural history of hemoglobin H disease, a subtype of α-thalassemia., Methods: We analyzed longitudinal clinical data for patients with hemoglobin H disease arising from the deletion of three of four α-globin genes (HbH) and from hemoglobin H Constant Spring (HCS), caused by the deletion of two α-globin genes and the Constant Spring mutation., Results: We identified 86 patients with hemoglobin H disease (48 through newborn screening). Of these patients, 60 (70%) had HbH, 23 (27%) had HCS, and 3 (3%) had other, nondeletional forms of hemoglobin H disease. The parental ethnic background was Asian in 81% of patients, Hispanic in 5%, and African American in 3%, whereas mixed ancestry was observed in 10% of patients. Among the patients with deletional hemoglobin H disease, 15% had one or both parents with African-American ancestry. Growth was normal in patients with HbH during the first decade, but growth deficits began during infancy in those with HCS. Anemia was more severe in patients with HCS at all ages (P<0.001). Acute worsening of anemia with infections requiring urgent blood transfusion was observed in patients with HCS but not in those with HbH. The probability of receiving at least one transfusion by the age of 20 years was 3% for patients with HbH and 80% for those with HCS (P<0.001). Among patients with HCS, transfusions occurred in 13% of infants and 50% of children under the age of 6 years; splenectomy was associated with a significant improvement in hemoglobin levels (P=0.01) and a reduction in the number of transfusions., Conclusions: HCS should be recognized as a distinct thalassemia syndrome with a high risk of life-threatening anemia during febrile illnesses. HbH was not associated with an increased rate of severe anemia with infections and was managed without blood transfusions. Many patients with these disorders had mixed ethnic backgrounds, which highlights the need for extended newborn screening in populations that are traditionally considered to be at low risk for hemoglobin H disease.

To monitor the exposure of Canadian populations, Health Canada has carried out six major surveys of breast milk contaminants, beginning in 1967. In these national surveys, breast milk was collected from nursing mothers at various times in their nursing period, and the concentrations of chlorinated hydrocarbons were measured. There was a downward trend from 1967 to 1992, in the concentrations of organochlorine (OC) pesticides and polychorinated biphenyl hydrocarbons (PCBs). This regression was observed for samples across Canada, except for a sharp isolated increase in 1982 for the Quebec Province. As the disappearance curves of the chemicals surveyed follow the same pattern for both Ontario and Canada, a similar decline could be expected of OC concentrations in human breast milk in the Great Lakes Basin.

This study was designed to investigate the relationship between loneliness and self-esteem for adolescents (n = 57; age range 16 to 18 years). As hypothesized, scores on the UCLA Scale for Loneliness correlated negatively with adolescents' scores on Coopersmith's self-esteem measure. And, scores on two affective dimensions of loneliness (Isolation and Dejection) correlated negatively with scores on self-esteem.