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Miyata R.,University of British Columbia | Bai N.,University of British Columbia | Vincent R.,Healthy Environmental | Sin D.D.,University of British Columbia | Van Eeden S.F.,University of British Columbia
Chest | Year: 2013

Background: The 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) suppress ambient particulate matter , 10 m m (PM 10 )-induced infl ammatory response in vitro. The aim of this study was to determine the effect of statins on PM 10 -induced lung infl ammation in vivo. Methods: New Zealand white rabbits were exposed to either PM 10 (1.0 mg/kg) or saline by direct intratracheal instillation three times a week for 4 weeks - lovastatin 5.0 mg/kg/d. BAL fluid was assessed for cell counts and proinfl ammatory cytokine levels. Lung infl ammation was quantifi ed using immunohistochemical techniques and morphometric methods. Ex vivo phagocytosis assay of alveolar macrophages using PM 10 particles was performed. Distribution of PM 10 particles in lung tissues and draining lymph nodes was quantifi ed morphometrically to evaluate the clearance of PM 10 particles. Results: PM 10 exposure increased the production of IL-6 and IL-8, promoted the recruitment of macrophages and polymorphonuclear leukocytes into the lung, and activated these recruited leukocytes. Lovastatin signifi cantly suppressed all these effects. Lovastatin increased the phagocytic activity of macrophages and promoted the migration of PM 10 -laden macrophages to the regional lymph nodes. Conclusions: Lovastatin attenuates the PM 10 -induced recruitment and activation of alveolar macrophages and polymorphonuclear leukocytes, reduces local proinfl ammatory cytokine production, and promotes the clearance of PM 10 particles from lung tissues to regional lymph nodes. These novel pleiotropic properties of statins are most likely to contribute to the downregulation of PM 10 -induced lung infl ammation. CHEST 2013; 143(2):452-460 © 2013 American College of Chest Physicians.

Curren M.S.,Chemicals Surveillance Bureau | Davis K.,Healthy Environmental
International Journal of Circumpolar Health | Year: 2014

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. © 2014 Meredith S. Curren et al.

Kaland N.,Lillehammer University College | Mortensen E.L.,Healthy Environmental | Smith L.,A+ Network | Smith L.,University of Oslo
Research in Autism Spectrum Disorders | Year: 2011

In the present study children and adolescents with Asperger syndrome (N = 13) and a matched control group of typically developing children and adolescents were presented with 26 vignettes of daily life situations, including irony, metaphors, contrary emotions, jealousy, social blunders, and understanding intentions. The participants in the AS group showed significant impairments in social communication. They needed significantly longer response times to solve the tasks and required significantly more prompt questions than the control persons. When analyzing the AS participants' performances before any prompt questions had been given, their task performances were significantly poorer than after the prompts had been given indicating that without any prompt questions their task performance would have fallen markedly. © 2011 Elsevier Ltd. All rights reserved.

Boothe V.L.,Scientific-Atlanta | Boehmer T.K.,National Center for Environmental Health | Wendel A.M.,Healthy Environmental | Yip F.Y.,National Center for Environmental Health
American Journal of Preventive Medicine | Year: 2014

Context Exposure to elevated concentrations of traffic-related air pollutants in the near-road environment is associated with numerous adverse human health effects, including childhood cancer, which has been increasing since 1975. Results of individual epidemiologic studies have been inconsistent. Therefore, a meta-analysis was performed to examine the association between residential traffic exposure and childhood cancer. Evidence acquisition Studies published between January 1980 and July 2011 were retrieved from a systematic search of 18 bibliographic databases. Nine studies meeting the inclusion criteria were identified. Weighted summary ORs were calculated using a random effects model for outcomes with four or more studies. Subgroup and sensitivity analyses were performed. Evidence synthesis Childhood leukemia was positively associated (summary OR=1.53, 95% CI=1.12, 2.10) with residential traffic exposure among seven studies using a postnatal exposure window (e.g., childhood period or diagnosis address) and there was no association (summary OR=0.92, 95% CI=0.78, 1.09) among four studies using a prenatal exposure window (e.g., pregnancy period or birth address). There were too few studies to analyze other childhood cancer outcomes. Conclusions Current evidence suggests that childhood leukemia is associated with residential traffic exposure during the postnatal period, but not during the prenatal period. Additional well-designed epidemiologic studies that use complete residential history to estimate traffic exposure, examine leukemia subtypes, and control for potential confounding factors are needed to confirm these findings. As many people reside near busy roads, especially in urban areas, precautionary public health messages and interventions designed to reduce population exposure to traffic might be warranted. © 2014 American Journal of Preventive Medicine.

Saravanabhavan G.,Chemicals Surveillance Bureau | Guay M.,Healthy Environmental | Langlois T.,Institute National Of Sante Publique Du Quebec | Giroux S.,Statistics Canada | And 2 more authors.
International Journal of Hygiene and Environmental Health | Year: 2013

Human exposure to phthalates occurs through multiple sources and pathways. In the Canadian Health Measures Survey 2007-2009, 11 phthalate metabolites, namely, MMP, MEP, MnBP, MBzP, MCHP, MCPP, MEHP, MEOHP, MEHHP, MnOP, and MiNP were measured in urine samples of 6-49 year old survey respondents (n=3236). The phthalate metabolites biomonitoring data from this nationally-representative Canadian survey are presented here. The metabolites MEP, MnBP, MBzP, MCPP, MEHP, MEOHP and MEHHP were detected in >90% of Canadians while MMP, MCHP, MnOP and MiNP were detected in <20% of the Canadian population. Step-wise regression analyses were carried out to identify important predictors of volumetric concentrations (μg/L) of the metabolites in the general population. Individual multiple regression models with covariates age, sex, creatinine, fasting status, and the interaction terms age. ×. creatinine, age. ×. sex and fasting status. ×. creatinine were constructed for MEP, MnBP, MBzP, MCPP, MEHP, MEOHP and MEHHP. The least square geometric mean (LSGM) estimates for volumetric concentration (μg/L) of the metabolites derived from respective regression models were used to assess the patterns in the metabolite concentrations among population sub-groups. The results indicate that children had significantly higher urinary concentrations of MnBP, MBzP, MEHP, MEHHP, MEOHP and MCPP than adolescents and adults. Moreover, MEP, MBzP, MnBP and MEOHP concentrations in females were significantly higher than in males. We observed that fasting status significantly affects the concentrations of MEHP, MEHHP, MEOHP, and MCPP metabolites analyzed in this study. Moreover, our results indicate that the sampling time could affect the DEHP metabolite concentrations in the general Canadian population. © 2013.

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