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Systemic Imidacloprid Affects Intraguild Parasitoids Differently

Toxoneuron nigriceps (Viereck) (Hymenoptera, Braconidae) and Campoletis sonorensis (Cameron) (Hymenoptera, Ichneumonidae) are solitary endoparasitoids of the tobacco budworm, Heliothis virescens (Fabricius) (Lepidoptera, Noctuidae). They provide biological control of H. virescens populations in Southeastern US agricultural production systems. Field and greenhouse experiments conducted from 2011–2014 compared parasitism rates of parasitoids that developed inside H. virescens larvae fed on tobacco plants treated with and without imidacloprid. The parasitoids in our study did not have a similar response. Toxoneuron nigriceps had reduced parasitism rates, but parasitism rates of C. sonorensis were unaffected. Preliminary data indicate that adult female lifespans of T. nigriceps are also reduced. ELISA was used to measure concentrations of neonicotinoids, imidacloprid and imidacloprid metabolites in H. virescens larvae that fed on imidacloprid-treated plants and in the parasitoids that fed on these larvae. Concentrations were detectable in the whole bodies of parasitized H. virescens larvae, T. nigriceps larvae and T. nigriceps adults, but not in C. sonorensis larvae and adults. These findings suggest that there are effects of imidacloprid on multiple trophic levels, and that insecticide use may differentially affect natural enemies with similar feeding niches.

Relationship between Urinary N-Desmethyl-Acetamiprid and Typical Symptoms including Neurological Findings: A Prevalence Case-Control Study

We previously determined a metabolite of acetamiprid, N-desmethyl-acetamiprid in the urine of a patient, who exhibited some typical symptoms including neurological findings. We sought to investigate the association between urinary N-desmethyl-acetamiprid and the symptoms by a prevalence case-control study. Spot urine samples were collected from 35 symptomatic patients of unknown origin and 50 non-symptomatic volunteers (non-symptomatic group, NSG, 4–87 year-old). Patients with recent memory loss, finger tremor, and more than five of six symptoms (headache, general fatigue, palpitation/chest pain, abdominal pain, muscle pain/weakness/spasm, and cough) were in the typical symptomatic group (TSG, n = 19, 5–69 year-old); the rest were in the atypical symptomatic group (ASG, n = 16, 5–78 year-old). N-desmethyl-acetamiprid and six neonicotinoids in the urine were quantified by liquid chromatography-tandem mass spectrometry. The detection of N-desmethyl-acetamiprid was the most frequent and highest in TSG (47.4%, 6.0 ppb (frequency, maximum)), followed by in ASG (12.5%, 4.4 ppb) and in NSG (6.0%, 2.2 ppb), however acetamiprid was not detected. Thiamethoxam was detected in TSG (31.6%, 1.4 ppb), in ASG (6.3%, 1.9 ppb), but not in NSG. Nitenpyram was detected in TSG (10.5%, 1.2 ppb), in ASG (6.3%, not quantified) and in NSG (2.0%, not quantified). Clothianidin was only detected in ASG (6.3%, not quantified), and in NSG (2.0%, 1.6 ppb). Thiacloprid was detected in ASG (6.3%, 0.1 ppb). The cases in TSG with detection of N-desmethyl-acetamiprid and thiamethoxam were aged 5 to 62 years and 13 to 62 years, respectively. Detection of N-desmethyl-acetamiprid was associated with increased prevalence of the symptoms (odds ratio: 14, 95% confidence interval: 3.5–57). Urinary N-desmethyl-acetamiprid can be used as a biomarker for environmental exposure to acetamiprid. Further multi-centered clinical research in larger patients groups with more metabolites analysis is needed

The number of insecticide spray applications on oilseed rape/canola continued to increase after introduction neonicotinoid insecticide seed treatments in 2000

Although pesticide treatment for oilseed rape (OSR) will vary from place to place and year to year, depending upon local conditions and needs, this review of pesticide usage on OSR between 1988 and 2014 has identified a long-term upward trend. Overall, the average number of pesticide treatments on OSR has more than doubled since 1994, accompanied by an increase in weight of pesticide active substances, from 2.1 kg/ha in 1994 to 3.3 kg/ha in 2014. The combined number of pesticide active substances has more than doubled during the same period. In respect of insecticides, the weight of insecticide active substances per hectare increased from 32 g/ha in 2002 to 50 g/ha in 2014. The number of insecticide spray rounds, products and active substances has also increased since 2002. Although Budge et al (2015) established that neonicotinoid seed coatings enabled farmers to reduce the number of insecticide sprays on OSR, this is not evident from the survey data after 2000 when neonicotinoid seed treatments were introduced. The weight of insecticide active substance per hectare and the number of insecticide spray applications has continued to increase after the introduction of neonicotinoid insecticide seed treatments in 2000.

Pathology reports on the first cows fed with Bt176 maize (1997–2002)

On an independent modern farm followed by certified veterinarians, dairy cows (mean of 62 per year) were maintained in optimized milk production for 3 years each. From 1997 to 2002, just after the commercial release of the first GMO (genetically modified organism) in Europe, genetically modified (GM) Bt176 maize grown on the farm was progressively introduced in controlled diets. The results are described in the following account, which has an historical value as it is the longest and first on-farm observation of mammals, performed by an experienced farmer and veterinarians, during a period of unusual pathological problems in cows receiving a GMO-rich diet. Thus it was not designed as a scientific experiment. Over the years, and coinciding with regular increases in GMO content of the diet (0–40%), the proportion of healthy cows with high milk yield diminished from 70% (normal rate) to only 40%. At the peak of mortalities in 2002, 10% of the cows died, preceded by a long-lasting paresis syndrome without hypocalcemia or fever, but with kidney biochemical failure and mucosa or epithelial problems. No microbial origin was identified, though intensively investigated. The GM maize, subsequently withdrawn from the market, was at the time the only intended managerial change for the cows. It is proposed that it provoked long-term toxic effects on mammals, which are not observable in most common conditions of intensive farming with high and rapid animal turnover and with no specific labels on GM feed (identifying amount and precise identity of GMO content). More long-term assessments during GMO feeding trials should be performed.

US EPA Codifies New Changes to FIFRA Minimum Risk Pesticide Requirements

On December 28, 2015, the U.S. Environmental Protection Agency (EPA) finalized important changes to the “minimum risk” pesticide exemption under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA). See EPA, “Pesticides; Revisions to Minimum Risk Exemption,” 80 Fed. Reg. 80653 (Dec. 28, 2015). EPA’s new rule goes into effect February 26, 2016, with the exception of the deadline for compliance with new labeling requirements for minimum risk products, which is February 26, 2019. EPA’s action follows changes proposed in December 2012 and marks the first set of revisions to EPA’s minimum risk pesticide regulations since the Agency originally promulgated them in 1996. As briefly summarized below, the changes include more detailed EPA listings of the active and inert ingredients that may be used in minimum risk pesticides. Although EPA has not added or subtracted any ingredients from its lists of eligible minimum risk product ingredients, in its survey of personal insect repellent products currently distributed as minimum risk pesticides, it found that nearly half contain ingredients not permitted by its regulations. Based on this analysis, EPA suggests that the more detailed listings included in its newly codified provisions may require manufacturers who currently distribute pesticides under the minimum risk exemption to reformulate their products to achieve compliance.

Decades of bat observations reveal uptick in new causes of mass mortality

Reports of bat deaths worldwide due to human causes largely unique to the 21st century are markedly rising, according to a new USGS-led analysis published in Mammal Review. Collisions with wind turbines worldwide and the disease white-nose syndrome in North America lead the reported causes of mass death in bats since the onset of the 21st century. These new threats now surpass all prior known causes of bat mortality, natural or attributed to humans. A comprehensive study reveals trends in the occurrence and causes of multiple mortality events in bats as reported globally for the past 200 years, shedding new light on the possible factors underlying population declines. "Many of the 1,300 species of bats on Earth are already considered threatened or declining. Bats require high survival to ensure stable or growing populations," said Tom O'Shea, a USGS emeritus research scientist and the study's lead author. "The new trends in reported human-related mortality may not be sustainable."

Biological Monitoring of Human Exposure to Neonicotinoids Using Urine Samples, and Neonicotinoid Excretion Kinetics

It has been suggested that several neonicotinoids cause neurodevelopmental toxicity in mammals. The aim was to establish the relationship between oral intake and urinary excretion of neonicotinoids by humans to facilitate biological monitoring, and to estimate dietary neonicotinoid intakes by Japanese adults. Deuterium-labeled neonicotinoid (acetamiprid, clothianidin, dinotefuran, and imidacloprid) microdoses were orally ingested by nine healthy adults, and 24 h pooled urine samples were collected for 4 consecutive days after dosing. The excretion kinetics were modeled using one- and two-compartment models, then validated in a non-deuterium-labeled neonicotinoid microdose study involving 12 healthy adults. Increased urinary concentrations of labeled neonicotinoids were observed after dosing. Clothianidin was recovered unchanged within 3 days, and most dinotefuran was recovered unchanged within 1 day. Around 10% of the imidacloprid dose was excreted unchanged. Most of the acetamiprid was metabolized to desmethyl-acetamiprid. Spot urine samples from 373 Japanese adults were analyzed for neonicotinoids, and daily intakes were estimated. The estimated average daily intake of these neonicotinoids was 0.53–3.66 μg/day. The highest intake of any of the neonicotinoids in the study population was 64.5 μg/day for dinotefuran, and this was <1% of the acceptable daily intake.

Replacing imidacloprid by another neonicotinoid does not reduce the environmental impact on mayfly nymphs

Mayfly nymphs are among the most sensitive taxa to neonicotinoids. The present study presents the acute and chronic toxicity of 3 neonicotinoids (imidacloprid, thiacloprid, and thiamethoxam) to a mayfly species (Cloeon dipterum) and some notes on the seasonality of the toxicity of imidacloprid to C. dipterum and 5 other invertebrate species. Imidacloprid and thiamethoxam showed equal acute and chronic toxicity to a winter generation of C. dipterum, whereas thiacloprid was approximately twice as toxic. The acute and chronic toxicity of imidacloprid was much higher for the C. dipterum summer generation than for the winter one. The acute toxicity differs by a factor of 20 for the 96-h 50% effective concentration (EC50) and by a factor of 5.4 for the chronic 28-d EC50. Temperature had only a slight effect on the sensitivity of C. dipterum to imidacloprid because we only found a factor of 1.7 difference in the 96-h EC50 between tests performed at 10 8C and 18 8C. The difference in sensitivity between summer and overwintering generations was also found for 3 other insect species. The results indicate that if the use and environmental fate of the 3 neonicotinoids are comparable, replacing imidacloprid by another neonicotinoid might not reduce the environmental impact on the mayfly nymph C. dipterum. The results also show the importance of reporting which generation is tested because sensitivity values of insects in the summer might be underestimated by the experiments performed with neonicotinoids and an overwintering population.

Why people are taking to the streets in Germany to demand an "Agrarwende" - or agricultural transformation

DW looks at why people are taking to the streets in Germany to demand an "Agrarwende" - or agricultural transformation. Issues include health concerns, protection of animals, and pollution impacts on water and climate. Under the motto "we're sick of it!", people in Berlin will hit the streets by the thousands on Saturday (01.16.2016) to protest for a transformation in agricultural systems. A broad coalition of more than 50 environmental, consumer, animal and farming groups have called for the demonstration, which coincides with the opening of Green Week in Berlin - the largest agricultural trade fair in the world.

Bumblebee learning and memory is impaired by chronic exposure to a neonicotinoid pesticide

Bumblebees are exposed to pesticides applied for crop protection while foraging on treated plants, with increasing evidence suggesting that this sublethal exposure has implications for pollinator declines. The challenges of navigating and learning to manipulate many different flowers underline the critical role learning plays for the foraging success and survival of bees. We assessed the impacts of both acute and chronic exposure to field-realistic levels of a widely applied neonicotinoid insecticide, thiamethoxam, on bumblebee odour learning and memory. Although bees exposed to acute doses showed conditioned responses less frequently than controls, we found no difference in the number of individuals able to learn at field-realistic exposure levels. However, following chronic pesticide exposure, bees exposed to field-realistic levels learnt more slowly and their short-term memory was significantly impaired following exposure to 2.4 ppb pesticide. These results indicate that field-realistic pesticide exposure can have appreciable impacts on learning and memory, with potential implications for essential individual behaviour and colony fitness.