Experimental studies investigating the effects of endocrine disruptors frequently identify potential unconventional dose-response relationships called non-monotonic dose-response (NMDR) relationships. Standardized approaches for investigating NMDR relationships in a risk assessment context are missing. The aim of this work was to develop criteria for assessing the strength of NMDR relationships. A literature search was conducted to identify published studies that report NMDR relationships with endocrine disruptors. Fifty-one experimental studies that investigated various effects associated with endocrine disruption elicited by many substances were selected. Scoring criteria were applied by adaptation of an approach previously used for identification of hormesis-type dose-response relationships. Out of the 148 NMDR relationships analyzed, 82 were categorized with this method as having a “moderate” to “high” level of plausibility for various effects. Numerous modes of action described in the literature can explain such phenomena. NMDR can arise from numerous molecular mechanisms such as opposing effects induced by multiple receptors differing by their affinity, receptor desensitization, negative feedback with increasing dose, or dose-dependent metabolism modulation. A stepwise decision tree was developed as a tool to standardize the analysis of NMDR relationships observed in the literature with the final aim to use these results in a Risk Assessment purpose. This decision tree was finally applied to studies focused on the effects of bisphenol A.

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-Shortly after the introduction of systemic insecticides, new problems were observed by beekeepers on honeybee colonies. The studies carried out under laboratory conditions have shown sublethal effects on honeybee behavior. However, it was not possible to reproduce under natural conditions the effects described by beekeepers on bee colonies. In addition, studies have revealed that many other factors could also be responsible for the dysfunction of honeybee colonies. Scientists agree that problems observed on the hives are the result of multifactorial effects. Measures concerning apicultural and agricultural practices are therefore necessary to improve honeybee colonies' health and to preserve the diversity of pollinators in France.Keywords: neonicotinoid / insecticide / flowering treatment / oilseed rape / faba Résumé -Les actions mises en oeuvre pour réduire l'impact des produits phytopharmaceutiques sur les insectes pollinisateurs en France. Après l'introduction des insecticides systémiques, de nouveaux problèmes ont été observés par les apiculteurs sur les colonies d'abeilles. Les nombreuses études réalisées depuis pour en identifier les causes ont mis en évidence des effets sur le comportement des abeilles, sans pour autant parvenir à reproduire en conditions naturelles les effets décrits par les apiculteurs sur les colonies. Par ailleurs, les études ont montré que bien d'autres facteurs pouvaient aussi expliquer les perturbations de leur fonctionnement. Les scientifiques s'accordent pour dire qu'il s'agit d'effets multifactoriels. Des actions visant les pratiques apicoles et agricoles sont donc nécessaires pour préserver les ruches et la diversité des pollinisateurs en France (the full text is available in French on http://www.ocl-journal.org/).

At the beginning of 2009, Parliament has adopted two directives to reduce utilizations of pesticides in Europe. Some Cut off criteria will be used after 2011 for the approval of active substances. This decision will affect the possibilities of chemical protection for the oilseed. A Pesticides Safety Directorate study shows that several herbicides, fungicides and insecticides actually used will be suspended, but without major impact for the crop protection, especially if expected innovations will be available next years.