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Pyrethroids are a class of plant-derived insecticides and their man-made analogues that are increasingly applied in Canada as first choice for pest control in many agricultural and residential settings. Their popularity is partly due to their alleged safety compared to the older organochlorine and organophosphate insecticides. Application of pyrethroids is expanding because of recent increases in the level of pest infestations--such as bed bugs and the decreased susceptibility of target species to many pest control products. Pyrethroid residues have been documented in homes, child care centres and food. While pyrethroids are considered of low health risk for humans, their increased use is of concern. Our current understanding of the adverse effects of pyrethroids derives mainly from studies of short-term effects in laboratory animals, case reports of self-and accidental poisonings, and high-dose occupational exposures, for which the levels and formulations of pyrethroid products differ from those relevant for long-term exposure in the general population. The available data suggest that the reproductive and nervous systems, endocrine signalling pathways, and early childhood development may be targets for adverse effects in the case of repeated exposure to pyrethroid formulations. Given uncertainty about the existence of long-term health effects of exposure to pyrethroids, particularly under realistic scenarios, we should be cautious when promoting pyrethroid products as safe methods for pest control. Key words: Pyrethrins; environmental exposure; endocrine disrupting chemicals; toxicology; risk assessment Les pyrethrinoides, une categorie d'insecticides derives des plantes et leurs analogues synthetiques, sont de plus en plus utilises au Canada comme premier choix dans la lutte antiparasitaire dans bien des contextes agricoles et residentiels. Leur popularite est due en partie a leur innocuite presumee comparativement aux insecticides organochlores et organophosphores plus anciens. La demande de pyrethrinoides augmente en raison des hausses recentes du niveau d'infestations par des insectes nuisibles (comme les punaises de lit) et de la vulnerabilite reduite des especes cibles a de nombreux produits de lutte antiparasitaire. Des residus de pyrethrinoides ont ete detectes dans des logements, des centres de la petite enfance et des aliments. Bien que l'on considere que les pyrethrinoides presentent peu de risques pour la sante humaine, leur utilisation croissante est un probleme. Nos connaissances actuelles des effets indesirables des pyrethrinoides decoulent principalement d'etudes de leurs effets a court terme sur des animaux de laboratoire, d'etudes de cas d'empoisonnement volontaire et accidentel, et de cas d'exposition professionnelle a des doses elevees; or, dans ces situations, les niveaux et les formulations des produits aux pyrethrinoides different de ceux qui s'appliqueraient a l'etude de leurs risques a long terme dans la population generale. Selon les donnees disponibles, l'appareil genital, le systeme nerveux, les voies de signalisation endocrinienne et le developpement du jeune enfant pourraient etre la cible d'effets indesirables en cas d'exposition repetee a des formulations a base de pyrethrinoides. Etant donne l'incertitude entourant l'existence d'effets a long terme sur la sante a la suite d'une exposition aux pyrethrinoides, surtout dans des scenarios realistes, la prudence est de mise lorsqu'on presente les produits aux pyrethrinoides comme des outils de lutte antiparasitaire sans danger. Mots cles : pyrethrine; exposition environnementale; perturbateurs endocriniens; toxicologie; evaluation du risque, Pyrethroid insecticides and naturally occurring pyrethrins are commonly used for insect control in households and in agriculture. (1) Reasons for this are increasing restrictions in the use of organophosphate and [...]

Objective: To share four Canadian cities' experiences with bed bug infestations and to explore public health roles in managing them. Methods: We summarize presentations from a workshop at the 2010 Canadian Public Health Association Conference which examined the re-emergence of bed bugs in Canada and compared management approaches of municipal and public health authorities in four large Canadian cities. We include updates on their activities since the workshop. Results: Cities across Canada have observed an increase in complaints of bed bug infestations over recent years. Toronto Public Health considers bed bugs to be a threat to health and has been heavily involved in the front-line response to bed bug complaints. In Winnipeg, Montreal and Vancouver, city inspectors are responsible for investigating complaints, and public health plays a supporting or secondary role. We identified factors that may contribute to successful management of bed bugs: sufficient funding, partnerships among many stakeholders, training and education, and surveillance and evaluation. Conclusion: Various public health agencies in Canadian cities have played key roles in the fight against bed bugs through new initiatives, education, and encouragement and support for others. By working with the public, owners, tenants, the health sector and other stakeholders, public health practitioners can begin to curb the resurgence of bed bugs and the social strains associated with them. Key words: Bed bug; Cimex lectularuis; environmental health; public health Objectifs: Relater l'experience de quatre villes canadiennes aux prises avec des infestations de punaises de lit et analyser le role joue par la sante publique pour maitriser ces infestations. Methode: Nous resumons les presentations d'un atelier donne a la Conference 2010 de l'Association canadienne de sante publique, oU l'on a examine la reemergence des punaises de lit au Canada et compare les approches de prise en charge des autorites municipales et sanitaires dans quatre grandes villes canadiennes. Nous incluons des nouvelles de leurs activites depuis l'atelier. Resultats: De nombreuses villes du Canada observent une hausse des plaintes d'infestations de punaises de lit depuis quelques annees. Le Service de sante publique de Toronto, qui considere les punaises de lit comme une menace pour la sante, est tres implique dans les interventions de premiere ligne en cas de plainte d'infestation. A Winnipeg, Montreal et Vancouver, ce sont les inspecteurs de la ville qui sont charges d'enqueter sur les plaintes, la sante publique jouant un role secondaire ou de soutien. Nous avons recense les facteurs pouvant contribuer a une prise en charge efficace des punaises de lit : des fonds suffisants, des partenariats entre les nombreux acteurs du milieu, la formation et la sensibilisation, ainsi que la surveillance et l'evaluation. Conclusion: Divers organismes de sante publique dans les villes canadiennes jouent un role cle dans la lutte contre les punaises de lit en menant de nouvelles initiatives, en faisant de la sensibilisation, et en offrant soutien et encouragement a d'autres. En travaillant avec le public, les proprietaires, les locataires, le secteur de la sante et les autres acteurs, les praticiens de la sante publique peuvent esperer juguler la reapparition des punaises de lit et les tensions sociales qui en resultent. Mots cles: punaise lit; Cimex lectularuis; sante environnementale; sante publique, Bed bugs (Cimex lectularuis) are small, elusive insects that feed almost exclusively on human blood. Bed bug infestations have become prominent worldwide, generating increased public concern. (1,2) Despite the attention [...]

Objectives. We compared the ability of several heat--health warning systems to predict days of heat-associated mortality using common data sets. Methods. Heat-health warning systems initiate emergency public health interventions once forecasts have identified weather conditions to breach predetermined trigger levels. We examined 4 commonly used trigger-setting approaches: (1) synoptic classification, (2) epidemiologic assessment of the temperature--mortality relationship, (3) temperature--humidity index, and (4) physiologic classification. We applied each approach in Chicago, Illinois; London, United Kingdom; Madrid, Spain; and Montreal, Canada, to identify days expected to be associated with the highest heat-related mortality. Results. We found little agreement across the approaches in which days were identified as most dangerous. In general, days identified by temperature-mortality assessment were associated with the highest excess mortality. Conclusions. Triggering of alert days and ultimately the initiation of emergency responses by a heat-health warning system varies significantly across approaches adopted to establish triggers. (Am J Public Health. 2010;100: 1137-1144. doi: 10.2105/AJPH.2009.169748)

BACKGROUND: Congenital heart defects may be environmentally related, but the association with elevated ambient temperature has received little attention. OBJECTIVES: We studied the relationship between outdoor heat during the first trimester of pregnancy and risk of congenital heart defects. METHODS: We carried out a retrospective cohort study of 704,209 fetuses between 2 and 8 weeks postconception from April to September in Quebec, Canada, 1988-2012. We calculated the prevalence of congenital heart defects at birth according to the number of days women were exposed to maximum temperature ≥ 30°C. In log-binomial regression models, we estimated prevalence ratios (PR) and 95% confidence intervals (CI) for the relationship of temperature with seven critical and eight noncritical heart defects, adjusted for pregnancy characteristics. RESULTS: Prevalence of congenital heart defects was 979.5 per 100,000 for 10 days or more of temperature ≥ 30°C compared with 878.9 per 100,000 for 0 days of exposure. Temperature was more precisely associated with noncritical than critical defects, which had lower prevalence. Fetuses exposed to 15 days of temperature ≥ 30°C between 2 and 8 weeks post-conception had 1.06 times the risk of critical defects (95% CI: 0.67, 1.67) and 1.12 times the risk of noncritical defects (95% CI: 0.98, 1.29) relative to 0 days. Associations were higher for atrial septal defects (PR 1.37, 95% CI: 1.10, 1.70) than for other noncritical defects. For atrial septal defects, associations with elevated temperatures began the 3rd week postconception. CONCLUSIONS: Extreme heat exposure during the first trimester may be associated with noncritical heart defects, especially of the atrial septum. http://dx.doi.org/10.1289/EHP171., Introduction Congenital heart defects are a leading congenital anomaly worldwide, occurring in every 8 live births per 1,000 (van der Linde et al. 2011). Most congenital heart defects are noncritical, [...]

Background: As the COVID-19 pandemic continues to unfold, increasing numbers of Canadians have self-medicated with ivermectin, an antiparasitic drug used to treat infections and infestations in humans and livestock. This is despite a lack of goodquality evidence for its efficacy in preventing and treating infection with SARS CoV-2. Concerns over unsafe use of ivermectin prompted a review of calls to the British Columbia Drug and Poison Information Centre. Methods: We performed a descriptive analysis of calls received from 1 January 2018 to 11 October 2021 about exposure to ivermectin and related compounds. Results: The BC Drug and Poison Information Centre received 50 calls concerning exposure to ivermectin and related compounds during the period we studied. Prior to the COVID-19 pandemic, 23 calls were made, and all but one were unintentional exposures. The first ivermectin call referencing COVID-19 was received in March 2021, after which call frequency increased, leading to 27 more calls, of which 19 were intentional exposures to ivermectin referencing COVID-19. Of these calls, 11 concerned veterinary-grade ivermectin, and where doses were calculable, at 0.147-11.91 mg/kg, they were above the 0.15-0.2mg/kg therapeutic dose for most approved human uses. Three exposures were asymptomatic, 11 were considered to have minor effects, 1 was moderate, 4 were symptomatic but considered unrelated to ivermectin, and in 1 case symptoms were not recorded. Conclusions: The use of ivermectin to prevent or treat COVID-19 is occurring in British Columbia, and both human and veterinary formulations are being ingested. Our case review suggests that these exposures occur most frequently in more agricultural regions, where the portion of adults vaccinated against COVID-19 has been lower and the portion infected higher than elsewhere in the province. [ABSTRACT FROM AUTHOR]