Safeguarding pollinators and their values to human well-being

Wild and managed pollinators provide a wide range of benefits to society in terms of contributions to food security, farmer and beekeeper livelihoods, social and cultural values, as well as the maintenance of wider biodiversity and ecosystem stability. Pollinators face numerous threats, including changes in land-use and management intensity, climate change, pesticides and genetically modified crops, pollinator management and pathogens, and invasive alien species. There are well-documented declines in some wild and managed pollinators in several regions of the world. However, many effective policy and management responses can be implemented to safeguard pollinators and sustain pollination services

Seed coating with a neonicotinoid insecticide negatively affects wild bees.

Understanding the effects of neonicotinoid insecticides on bees is vital because of reported declines in bee diversity and distribution and the crucial role bees have as pollinators in ecosystems and agriculture. Neonicotinoids are suspected to pose an unacceptable risk to bees, partly because of their systemic uptake in plants, and the European Union has therefore introduced a moratorium on three neonicotinoids as seed coatings in flowering crops that attract bees. The moratorium has been criticized for being based on weak evidence, particularly because effects have mostly been measured on bees that have been artificially fed neonicotinoids. Thus, the key question is how neonicotinoids influence bees, and wild bees in particular, in real-world agricultural landscapes. Here we show that a commonly used insecticide seed coating in a flowering crop can have serious consequences for wild bees. In a study with replicated and matched landscapes, we found that seed coating with Elado, an insecticide containing a combination of the neonicotinoid clothianidin and the non-systemic pyrethroid β-cyfluthrin, applied to oilseed rape seeds, reduced wild bee density, solitary bee nesting, and bumblebee colony growth and reproduction under field conditions. Hence, such insecticidal use can pose a substantial risk to wild bees in agricultural landscapes, and the contribution of pesticides to the global decline of wild bees may have been underestimated. The lack of a significant response in honeybee colonies suggests that reported pesticide effects on honeybees cannot always be extrapolated to wild bees

Secondary Targets of Nitrite-Derived Reactive Nitrogen Species: Nitrosation/Nitration Pathways, Antioxidant Defense Mechanisms and Toxicological Implications.

A review. Nitrite, the primary metabolite of nitric oxide (NO) and a widely diffused component of human diet, plays distinct and increasingly appreciated roles in human physiol. However, when exposed to acidic environments, typically in the stomach, or under oxidative stress conditions, it may be converted to a range of reactive nitrogen species (RNS) which in turn can target a variety of biomols. Typical consequences of toxicol. relevance include protein modification, DNA base deamination and the formation of N-nitrosamines, among the most potent mutagenic and carcinogenic compds. for humans. Besides primary biomols., nitrite can cause structural modifications to a variety of endogenous and exogenous org. compds., ranging from polyunsatd. fatty acids to estrogens, tocopherol, catecholamines, furans, retinoids, dietary phenols, and a range of xenobiotics. The study of the interactions between nitrite and key food components, including phenolic antioxidants, has therefore emerged as an area of great promise for delineating innovative strategies in cancer chemoprevention. Depending on substrates and conditions, diverse reaction pathways may compete to det. product features and distribution patterns. These include nitrosation and nitration but also oxidn., via electron transfer to nitrosonium ion or nitrogen dioxide. This contribution aims to provide an overview of the main classes of compds. that can be targeted by nitrite and to discuss at chem. levels the possible reaction mechanisms under conditions that model those occurring in the stomach. The toxicol. implications of the nitrite-modified mols. are finally addressed, and a rational chem. approach to the design of potent antinitrosing agents is illustrated