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Background: Studies have reported increasing incidence rates of paediatric diabetes, especially among those aged 0-5 years. Epidemiological evidence linking ambient air pollution to paediatric diabetes remains mixed., Objective: This study investigated the association between maternal and early-life exposures to common air pollutants (NO 2 , PM 2.5 , O 3 , and oxidant capacity [Ox; the redox-weighted average of O 3 and NO 2 ]) and the incidence of paediatric diabetes in children up to 6 years of age., Methods: All registered singleton births in Ontario, Ca nada occurring between April 1st , 2006 and March 31st , 2012 were included through linkage from health administrative data. Monthly exposures to NO 2 , PM 2.5 , O 3 , and O x were estimated across trimesters, the entire pregnancy period and during childhood. Random effects Cox proportional hazards models were used to assess the relationships with paediatric diabetes incidence while controlling for important covariates. We also modelled the shape of concentration-response (CR) relationships., Results: There were 1094 children out of a cohort of 754,698 diagnosed with diabetes before the age of six. O 3 exposures during the first trimester of pregnancy were associated with paediatric diabetes incidence (hazard ratio (HR) per interquartile (IQR) increase = 2.00, 95% CI: 1.04-3.86). The CR relationship between O 3 during the first trimester and paediatric diabetes incidence appeared to have a risk threshold, in which there was little-to-no risk below 25 ppb of O 3 , while above this level risk increased sigmoidally. No other associations were observed., Conclusion: O 3 exposures during a critical period of development were associated with an increased risk of paediatric diabetes incidence., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Crown Copyright © 2020. Published by Elsevier Inc. All rights reserved.) more...

Background: Cardiovascular malformations account for nearly one-third of all congenital anomalies, making these the most common type of birth defects. Little is known regarding the influence of ambient ultrafine particles (<0.1 μm) (UFPs) on their occurrence., Objective: This population-based study examined the association between prenatal exposure to UFPs and congenital heart defects (CHDs)., Methods: A total of 158,743 singleton live births occurring in the City of Toronto, Canada between April 1st 2006 and March 31st 2012 were identified from a birth registry. Associations between exposure to ambient UFPs between the 2nd and 8th week post conception when the foetal heart begins to form and CHDs identified at birth were estimated using random-effects logistic regression models, adjusting for personal- and neighbourhood-level covariates. We also investigated multi-pollutant models accounting for co-exposures to PM 2.5, NO 2 and O 3 ., Results: A total of 1468 CHDs were identified. In fully adjusted models, UFP exposures during weeks 2 to 8 of pregnancy were not associated with overall CHDs (Odds Ratio (OR) per interquartile (IQR) increase = 1.02, 95% CI: 0.96-1.08). When investigating subtypes of CHDs, UFP exposures were associated with ventricular septal defects (Odds Ratio (OR) per interquartile (IQR) increase = 1.13, 95% CI: 1.03-1.33), but not with atrial septal defect (Odds Ratio (OR) per interquartile (IQR) increase = 0.89, 95% CI: 0.74-1.06)., Conclusion: This is the first study to evaluate the association between prenatal exposure to UFPs and the risk of CHDs. UFP exposures during a critical period of embryogenesis were associated with an increased risk of ventricular septal defect., (Crown Copyright © 2019. Published by Elsevier Ltd. All rights reserved.) more...

Background: National health surveys are sometimes used to provide estimates on risk factors for policy and program development at the regional/local level. However, as regional/local needs may differ from national ones, an important question is how to also enhance capacity for risk factor surveillance regionally/locally., Methods: A Think Tank Forum was convened in Canada to discuss the needs, characteristics, coordination, tools and next steps to build capacity for regional/local risk factor surveillance. A series of follow up activities to review the relevant issues pertaining to needs, characteristics and capacity of risk factor surveillance were conducted., Results: Results confirmed the need for a regional/local risk factor surveillance system that is flexible, timely, of good quality, having a communication plan, and responsive to local needs. It is important to conduct an environmental scan and a gap analysis, to develop a common vision, to build central and local coordination and leadership, to build on existing tools and resources, and to use innovation., Conclusions: Findings of the Think Tank Forum are important for building surveillance capacity at the local/county level, both in Canada and globally. This paper provides a follow-up review of the findings based on progress over the last 4 years. more...

Background: An outbreak of Escherichia coli O157:H7 infection was identified in the spring of 1998, with a 7-fold increase in the number of laboratory-confirmed E. coli O157:H7 cases in southern Ontario. This prompted an intensive investigation by local, provincial and federal public health officials., Methods: Case interviews of 25 people from southern Ontario were conducted using a broad food history and environmental exposure survey. Laboratory investigations involved both case and food sampling. Specimens of foods sold locally and reportedly consumed by those affected were tested. Common suppliers of suspected foods were identified by cross-referencing suppliers' lists with stores frequented by those who fell ill. A case-control study involving 25 cases and 49 age-matched controls was conducted. This was followed by a comprehensive environmental investigation of the meat processing plant identified as the source of the E. coli., Results: Thirty-nine outbreak-related cases occurred between April 3 and June 2, 1998. Of the 36 case specimens tested all were positive for E. coli O157:H7. The case-control study identified Genoa salami as the most probable (odds ratio 8 [confidence interval 2-35]) source of the outbreak. Samples of Genoa salami produced by the most commonly identified supplier later tested positive for E. coli O157:H7, and the pathogen matched the same pulsed-field gel electrophoresis pattern and phage type of the case specimens., Interpretation: Our investigation, which led to a national recall of the brand of dry fermented Genoa salami identified as the source of the outbreak, supports an adherence to stringent manufacturing requirements for fermented meat products. A review of the Canadian standards for fermented meat processing and the effectiveness of their implementation is warranted. more...