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Conservationists are alarmed by the increasing number of birds under threat due to the damage being done to the earth's ecosystems. The most recent assessment for the International Union for Conservation of Nature Red List for endangered birds revealed that no less than 1,300 species are threatened with extinction. It means that if nothing is done, more than 1,000 species could disappear; disturbing and damaging the natural environment.

The European Food Safety Authority (EFSA) was asked by the European Commission (EC) to develop a Guidance Document on the risk assessment of plant protection products on bees. The Guidance Document is intended to provide guidance for notifiers and authorities in the context of the review of plant protection products (PPPs) and their active substances under Regulation (EC) 1107/2009. The scientific opinion on the science behind the development of a risk assessment of plant protection products on bees (Apis mellifera, Bombus spp. and solitary bees) (EFSA Panel on Plant Protection Poducts and their Residues (PPR), 2012a) provided the scientific basis for the development of the Guidance Document. The process of the development of the Guidance Document follows the methodology of definition of specific protection goals (SPGs) as outlined in the scientific opinion of EFSA‘s Plant Protection Products and their Residues Panel (EFSA Panel on Plant Protection Products and their Residues (PPR), 2010). The Standing Committee on the Food Chain and Animal Health was consulted for the appropriate levels of protection (e.g. to make choices on the magnitude of effects, duration of effects and exposure percentiles). The Guidance Document suggests the implementation of a tiered risk assessment scheme with a simple and cost-effective first tier to more complex higher tier studies under field conditions. Each of the tiers will have to ensure that the appropriate level of protection is achieved. More detailed guidance on specific aspects of laboratory studies and higher tier risk assessments is given in the appendices. A need for test protocols for bumble bees and solitary bees was identified. Potential protocols are available in the published literature and first proposals are made in the appendices. It is important that fully validated test protocols are developed in future.

Previous research has suggested positive associations between parental or childhood exposure to pesticides and risk of childhood brain tumors (CBT). This Australian case–control study of CBT investigated whether exposures to pesticides before pregnancy, during pregnancy and during childhood, were associated with an increased risk. Cases were recruited from 10 pediatric oncology centers, and controls by random-digit dialing, frequency matched on age, sex, and State of residence. Exposure data were collected by written questionnaires and telephone interviews. Data were analyzed by unconditional logistic regression. The odds ratios (ORs) for professional pest control treatments in the home in the year before the index pregnancy, during the pregnancy, and after the child’s birth were 1.54 (95 % confidence interval (CI): 1.07, 2.22), 1.52 (95 % CI: 0.99, 2.34) and 1.04 (95 % CI: 0.75, 1.43), respectively. ORs for treatments exclusively before pregnancy and during pregnancy were 1.90 (95 % CI: 1.08, 3.36) and 1.02 (95 % CI: 0.35, 3.00), respectively. The OR for the father being home during the treatment was 1.79 (95 % CI: 0.85, 3.80). The OR for paternal occupational exposure in the year before the child’s conception was 1.36 (95 % CI: 0.66, 2.80). ORs for prenatal home pesticide exposure were elevated for low- and high-grade gliomas; effect estimates for other CBT subtypes varied and lacked precision. These results suggest that preconception pesticide exposure, and possibly exposure during pregnancy, is associated with an increased CBT risk. It may be advisable for both parents to avoid pesticide exposure during this time.

Dose- and term-dependent differences in the location and nature of brain lesions induced in rats and dogs by 2,5-hexanedione (2,5-HD), misonidazole, clioquinol, and acrylamide are reported. Subchronic neuropathies ("distal axonopathy") were induced by low-dose administration of these neurotoxicants and at high doses, lesions caused by acute or subacute neurotoxicity were found in the central nervous system (CNS). In rats, 2,5-HD induced extracellular edema, nerve cell degeneration, and axonal degeneration in the cerebellar and vestibular nuclei. Similar lesions were observed in misonidazole-treated dogs and clioquinol induced nerve cell degeneration in the hippocampus and malacia in the piriform lobes of these animals. In rats, acrylamide induced degeneration of Purkinje cells. Although the mechanism(s) underlying the differential neurotoxicity of high and low doses of these neurotoxicants remains unclear, we suggest certain biochemical mechanisms, cytotoxic edema and excitotoxicity, as factors in the production of such lesions after high-dose treatment.

New research by academics at The University of Nottingham has shown that exposure to imidacloprid causes changes to the genes of the honeybee. The study, led by Dr Reinhard Stöger, Associate Professor in Epigenetics in the University's School of Biosciences, was conducted under field realistic conditions and showed that a very low exposure of just two parts per billion of imidacloprid has an impact on the activity of some of the honeybee genes. The researchers identified that cells of honeybee larvae had to work harder and increase the activity of genes involved in breaking down toxins, most likely to cope with the insecticide. Genes involved in regulating energy to run cells were also affected. Such changes are known to reduce the lifespan of the most widely studied insect, the common fruit fly, and lower a larva's probability of surviving to adulthood. Dr Stöger said: "Although larvae can still grow and develop in the presence of imidacloprid, the stability of the developmental process appears to be compromised. Should the bees be exposed to additional stresses such as pests, disease and bad weather then it is likely to increase the rate of development failure."

MORE than half of Ireland's honeybee population has been wiped out since winter, say beekeepers, who have described the losses as a "complete and utter meltdown". Varroa mites and their related diseases, poor breeding and two years of bad weather have played a big role in decimating bee numbers. But beekeepers are also blaming a controversial range of new agricultural pesticides – neonicotinoids – for contributing to the losses of between 50pc and 80pc of Irish hives this year. In the UK, reports of 60pc losses spurred the government there to last week launch what it described as an "urgent review" of the bee crisis. According to the Federation of Irish Beekeepers' Associations (FIBA), the wipeout among its 2,000-plus members is the worst ever. It estimates that Irish hive numbers have fallen below 10,000 from more than 20,000 before winter.

The survival of a species depends on its capacity to adjust to changing environmental conditions, and new stressors. Such new, anthropogenic stressors include the neonicotinoid class of crop-protecting agents, which have been implicated in the population declines of pollinating insects, including honeybees (Apis mellifera). The low-dose effects of these compounds on larval development and physiological responses have remained largely unknown. Over a period of 15 days, we provided syrup tainted with low levels (2 µg/L−1) of the neonicotinoid insecticide imidacloprid to beehives located in the field. We measured transcript levels by RNA sequencing and established lipid profiles using liquid chromatography coupled with mass spectrometry from worker-bee larvae of imidacloprid-exposed (IE) and unexposed, control (C) hives.

The negative effects of a commonly applied systemic insecticide, neonicotinoid, on the honey bee Apis mellifera L. are of great concern worldwide, as the use of the chemical is expanding. Recently, special attention has been paid to the sublethal effects of insecticides. An increasing number of studies has identified sublethal effects on the honey bee in the laboratory or in experimental cages, but so far, few studies have examined sublethal effects in the field. To reveal sublethal effects under field conditions, I examined whether the proportion of successful homing flights by foraging honey bees during 30 min after release decreased after bees were topically exposed to insecticides. Honey bees were treated with two types of neonicotinoid insecticide (clothianidin, dinotefuran) and two types of previously common insecticide (etofenprox [pyrethroid] and fenitrothion [organophosphate]) at five different doses (one-half, one-fourth, one-tenth, one-twentieth, and one-fortieth of their median lethal dose - LD50). Then the bees were released 500 m from their hives in the field.

Of the 21 species associated with farmland in Sweden, 15 (71%) displayed a significant decline (P < 0.05) in numbers between 1976 and 2001. Farmland specialists and generalists differed in their population trend estimates. The total declines based on the geometric mean for farmland specialists and generalists were 55% and 7%, respectively. Only the greenfinch Carduelis chloris L. increased significantly in numbers, whereas five species showed non-significant population trends. Seven species experienced average population declines of more than 50% (curlew Numenius arquata L, stock dove Columba oenas L., wryneck Jynx torquilla L., skylark Alauda arvensis L., northern wheatear Oenanthe oenanthe L., house sparrow Passer domesticus L. and linnet Carduelis cannabina L.) of which the curlew experienced the greatest decline (average yearly decline of 7%). Our analyses showed that several farmland specialists have remarkably similar population trends in Sweden and England (e.g. skylark, linnet and yellowhammer Emberiza citrinella L.). This supports the view that the cause of the decline is connected to agriculture and that species with specialist requirements are most sensitive to agricultural change.

Bees in agricultural landscapes are exposed to dietary pesticides such as imidacloprid when they feed from treated mass-flowering crops. Concern about the consequent impact on bees makes it important to understand their resilience. In the laboratory, we therefore fed adult worker bees on dosed syrup (125 µg L-1 imidacloprid, 98 µg kg-1) either continuously or as a pulsed exposure and measured their behaviour (feeding and locomotory activity) and whole-body residues. On dosed syrup, honey bees maintained much lower bodily levels of imidacloprid than bumble bees (< 0.2 ng vs. 2.4 ng imidacloprid per bee). Dietary imidacloprid did not affect the behaviour of honey bees but it reduced feeding and locomotory activity in bumble bees. After the pulsed exposure, bumble bees cleared bodily imidacloprid after 48 hours and recovered behaviourally. We attribute the differential behavioural resilience of the two species to the observed differential in bodily residues. The ability of bumble bees to recover may be environmentally relevant in wild populations that face transitory exposures from the pulsed blooming of mass-flowering crops.