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OBJECTIVES: We present total mercury (THg) in blood of Canadians 6-79 years of age from the first to-date nationally- representative survey, the Canadian Health Measures Survey (CHMS). This analysis is particularly relevant in the context of recent changes to Health Canada's blood Hg guidance values. METHODS: We used data from cycle 1 (2007-2009) of the CHMS, in particular focussing on 5,319 respondents aged 6-79 years for whom blood THg data were available. We calculated descriptive statistics of blood Hg levels and analyzed the associations between blood THg levels and relevant variables. We also compared blood THg levels to existing Health Canada blood Hg guidance values. RESULTS: The geometric mean blood THg level of the Canadian population was 0.69 [micro]g/L (95% CI 0.56-0.86 [micro]g/L). The majority (97.8%) of Canadian women aged 16-49 years, including pregnant women, had blood Hg values below the provisional HC blood guidance value of 8 [micro]g/L. Mean blood THg levels were significantly higher in the 'other or mixed' (1.14 [micro]g/L, p = 0.0003) and Asian (1.41 [micro]g/L, p = 0.0476) groups compared to those who self-identified as solely Caucasian (0.62 [micro]g/L). There was however no significant difference between participants self-identified as Aboriginal Canadians versus Caucasians (0.56 [micro]g/L vs 0.62 [micro]g/L, p = 0.2902). Fish and shellfish consumption significantly influenced blood Hg levels, as did alcohol consumption and the presence of dental amalgams. CONCLUSION: This paper presents the first description of blood THg levels in the general Canadian population. These findings will serve as a national baseline for monitoring future changes should they arise. KEY WORDS: Mercury; methylmercury; blood; biomonitoring; Canada; Canadian Health Measures Survey OBJECTIFS: Nous presentons les concentrations en mercure total (HgT) dans le sang des Canadiens de 6 a 79 ans tirees de la premiere enquete representative nationale a ce jour: l'Enquete canadienne sur les mesures de la sante (ECMS). Notre analyse est particulierement pertinente dans le contexte des modifications recentes aux valeurs de reference de Sante Canada pour le Hg sanguin. METHODE: Nos donnees proviennent du cycle 1 (2007-2009) de l'ECMS, plus precisement des 5 319 repondants de 6 a 79 ans pour lesquels il existe des donnees sur le mercure total dans le sang. Nous avons fait des calculs de statistique descriptive pour les concentrations en Hg sanguin et analyse les associations entre les concentrations en HgT dans le sang et les variables pertinentes. Nous avons aussi compare les concentrations en HgT dans le sang aux valeurs de reference existantes de Sante Canada pour le Hg sanguin. RESULTATS: La moyenne geometrique des concentrations en HgT dans le sang de la population canadienne est de 0,69 [micron]g/L (IC de 95%: 0,56-0,86 [micron]g/L). La majorite (97,8%) des Canadiennes de 16 a 49 ans, y compris les femmes enceintes, ont des valeurs de Hg sanguin inferieures a la valeur de reference provisoire de Sante Canada (8 [micron]g/L). Les concentrations moyennes en HgT dans le sang sont sensiblement plus elevees dans les populations <> (1,14 [micron]g/L, p = 0,0003) et asiatiques (1,41 [micron]g/L, p = 0,0476) que dans la population s'identifiant comme blanche (0,62 [micron]g/L). Il n'y a toutefois aucun ecart significatif entre les participants s'identifiant comme des Canadiens autochtones ou blancs (0,56 [micron]g/L contre 0,62 [micron]g/L, p = 0,2902). La consommation de poissons, crustaces et coquillages influence de facon significative les concentrations en Hg sanguin, tout comme la consommation d'alcool et la presence d'amalgames dentaires. CONCLUSION: Cet article presente la premiere description des concentrations en HgT dans le sang de la population canadienne dans son ensemble. Nos constatations serviront de base de reference nationale pour la surveillance des changements eventuels. MOTS CLES: mercure; methylmercure; sang; biosurveillance; Canada; Enquete canadienne sur les mesures de la sante, Mercury (Hg) is a heavy metal and a constituent of the rocks within the Earth's crust. It is released from the crust through natural events and industrial processes. (1) Following [...]

BACKGROUND: Manganese neurotoxicity is well documented in individuals occupationally exposed to airborne particulates, but few data are available on risks from drinking-water exposure. OBJECTIVE: We examined associations of exposure from concentrations of manganese in water and hair with memory, attention, motor function, and parent- and teacher-reported hyperactive behaviors. METHODS: We recruited 375 children and measured manganese in home tap water (MnW) and hair (MnH). We estimated manganese intake from water ingestion. Using structural equation modeling, we estimated associations between neurobehavioral functions and MnH, MnW, and manganese intake from water. We evaluated exposure--response relationships using generalized additive models. RESULTS: After adjusting for potential confounders, a 1-SD increase in [log.sub.10] MnH was associated with a significant difference of -24% (95% CI: -36, -12%) SD in memory and -25% (95% CI: -41, -9%) SD in attention. The relations between [log.sub.10] MnH and poorer memory and attention were linear. A 1-SD increase in [log.sub.10] MnW was associated with a significant difference of -14% (95% CI: -24, -4%) SD in memory, and this relation was nonlinear, with a steeper decline in performance at MnW > 100 µg/L. A 1-SD increase in [log.sub.10] manganese intake from water was associated with a significant difference of -11% (95% CI: -21, -0.4%) SD in motor function. The relation between [log.sub.10] manganese intake and poorer motor function was linear. There was no significant association between manganese exposure and hyperactivity. CONCLUSION: Exposure to manganese in water was associated with poorer neurobehavioral performances in children, even at low levels commonly encountered in North America. Environ Health Perspect 122:1343-1350; http://dx.doi.org/10.1289/ehp.1307918, Introduction Manganese is widespread in the environment [Agency for Toxic Substances and Disease Registry (ATSDR) 2012]. It is an essential element, required for the function of many enzymes and involved [...]