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Although phytoseiids are best known as predators of phytophagous mites and other small arthropods, several species can also feed and reproduce on pollen. In laboratory assays, we assessed the profitability of two types of dietary supplements (three pollen species-cattail, maize and apple-and eggs of the Mediterranean flour moth, Ephestia kuehniella) for the two species of predatory mites most commonly used as biocontrol agents in horticulture in Canada, Neoseiulus cucumeris and Amblyseius swirskii. We measured the effects of each diet on phytoseiid fitness parameters (survival, development, sex ratio, fecundity) and, as a means of comparison, when fed larvae of the common targeted pest species, western flower thrips Frankliniella occidentalis. A soluble protein assay was also performed on the alternative food sources as protein content is often linked to high nutritive value according to the literature. All food sources tested were suitable for N. cucumeris and A. swirskii, both species being able to develop from egg to adult. The dietary supplements had a beneficial impact on biological parameters, mostly resulting in shorter development times and higher survival rates when compared to thrips larvae. Amblyseius swirskii exhibited a wider dietary range than N. cucumeris. Overall, flour moth eggs, cattail pollen and apple pollen are food sources of equal quality for A. swirskii, whereas apple and cattail pollen are better when it comes to N. cucumeris. In contrast, maize pollen is a less suitable food source for N. cucumeris and A. swirskii. Soluble protein content results did not match the prediction under which the most beneficial food source would contain the highest concentration in protein.

The life-course framework stresses the importance of social, psychosocial, and biological factors in early life on the development of later disease. From this perspective, the association between edentulousness of mothers and their children's caries risk has not been studied. Therefore, a sample of 6303 mother-child pairs was randomly selected in Quebec (Canada). Mothers (6039 dentate and 264 edentulous) completed a self-administered questionnaire, and their children, aged 5 to 9 years, were clinically examined. Bivariate analyses and multiple logistic regressions showed that edentulous mothers' children are more likely to experience caries on both primary [OR=1.7 (1.3-2.3)] and permanent [OR=1.4 (1.0-2.0)] dentitions when compared with dentate mothers' children. These results are independent of socio-economic status, age, gender, and children's oral-health-related behaviors. Our study is the first to show that edentulous mothers' children constitute a group at risk of caries. It also highlights the need for a better understanding of the mother-child transmission of risk.

Two sequential sampling plans were developed to produce tools to reduce the use of pesticides for the control of the hairy chinch bug, Blissus leucopterus hirtus Montandon, on turfgrass lawns in the cool-humid region of Quebec, Canada. A first plan based on Wald's method was shown to be too conservative in a validation conducted on infested lawns. The second plan developed using Iwao's method yielded good results. The difference between the two plans may have occurred because no common k could be found for the negative binomial functions describing chinch bug distribution on lawns, thereby violating an essential assumption of Wald's approach. Application of the Iwao plan, which is based on visual sampling of 0.1-m2 quadrats, requires approximately 20 min when lawn evaluation is conducted by a single person. Estimation of the occurrence of chinch bug infestations (28% infested lawns in the regions of Montreal and Quebec cities), and results from validation of the Iwao plan on infested lawns, indicate that the error rates alpha and beta of the plan are lower than an upper limit of 0.05 and 0.14, respectively. The adequate precision and practicality of this plan suggest that it could become an essential tool for management of turfgrass lawns in regions where the hairy chinch bug completes less than two generations per growing season.

During the next few decades, actions on matters dealing with environmental pollution will have to be aimed at: 1) eliminating environmental contaminants at the source; 2) identifying biomarkers of exposure and/or adverse health effects; 3) improving our skills at assessing the probability of occurrence of adverse health effects in the community; and 4) informing the Canadian public in a responsible manner. Primary sources of pollution related to human activities should be our deep concern: utilization of energy sources, particularly fossil fuels; agricultural activities, such as deforestation and use of fertilizers and pesticides; and industrialization, responsible for the synthesis of numerous new molecules. Clinical investigators will be faced with rare disease entities characterized by low-level, long-term exposure via food, air, water and soil, and low-incidence responses (e.g. cancer, neurotoxicity, reproductive failure, immunotoxicity). Epidemiologists and toxicologists will be pressed, by the Canadian public, to answer questions regarding the probability of occurrence of health effects as a result of exposure to environmental contaminants. Collectively, as scientists, our attitudes will have to change drastically; high in the order of importance is the need to communicate with the public and to diligently inform our fellow citizens about the relationship between health and environment. In doing so, we might find allies to support our claim that health research in Canada deserves much better support.