General

A mixture of insecticides used in corn production was monitored over a three-year period in a field study to determine how long each persists in the environment, where each insecticide travels within the corn field, and the efficacy of using soil-applied insecticides with genetically modified corn. The genetically modified corn contained the insecticidal Cry1Ab and Cry3Bb1 proteins (Bt corn) and the Cry1Ab protein was found to persist only during the corn growing season in soil, runoffwater, and runoff sediment with highest concentrations measured during pollination. Very low concentrations of Cry1Ab proteins were measured in soil collected in the non-Bt corn field, and no Cry1Ab proteins were detected in shallow groundwater or soil pore water. Clothianidin, a neonicotinoid insecticide used as a seed coating, was detected in all matrices and remained persistent throughout the year in soil pore water. Tefluthrin, a pyrethroid insecticide applied at planting to control corn rootworm larvae (Diabrotica spp., Coleoptera: Chrysomelidae) populations, was consistently detected in soil, runoff water, and runoff sediment during the corn growing season, but was not detected in groundwater or soil pore water. Tefluthrin did not have an effect on root damage from corn rootworm larvae feeding to Bt corn, but did prevent damage to non-Bt corn. A slight reduction in grain yield was observed in the non-Bt, no tefluthrin treatment when compared to all other treatments, but no significant difference in grain yield was observed among Bt corn treatments regardless of soil insecticide application. In the current study, the use of tefluthrin on Bt corn did not significantly affect crop damage or yield, and tefluthrin may travel off-site in runoff water and sediment.

A huge increase in the incidence and prevalence of chronic diseases has been reported in the United States (US) over the last 20 years. Similar increases have been seen globally. In the present study, US government databases were searched for GE crop data, glyphosate application data and disease epidemiological data. Correlation analyses were then performed on a total of 22 diseases in these time-series data sets. The Pearson correlation coefficients are highly significant (< 10-5) between glyphosate applications and hypertension (R = 0.923), stroke (R = 0.925), diabetes prevalence (R = 0.971), diabetes incidence (R = 0.935), obesity (R = 0.962), lipoprotein metabolism disorder (R = 0.973), Alzheimer’s (R = 0.917), senile dementia (R = 0.994), Parkinson's (R = 0.875), multiple sclerosis (R = 0.828), autism (R = 0.989), inflammatory bowel disease (R = 0.938), intestinal infections (R = 0.974), end stage renal disease (R = 0.975), acute kidney failure (R = 0.978), cancers of the thyroid (R = 0.988), liver (R = 0.960), bladder (R = 0.981), pancreas (R = 0.918), kidney (R = 0.973) and myeloid leukaemia (R = 0.878).

A study published in the journal Science, reveals that the number of slugs, spiders, worms and other invertebrates has fallen by 45 per cent over the past 35 years. Experts fear this will harm the planet as creepy crawlies play an important role in pollinating crops, pest control, decomposition and ensuring soil remains packed with nutrients, as well as water filtration. In the UK the number of beetles, butterflies, bees and wasps has fallen by up to 60 per cent. Experts warn that fewer insects would have a huge effect on crop production as up to 75 percent are pollinated by insects, amounting to around 10 per cent of the world's food supply. Scientists fear a drop in the insect population could also spark a decline in birds, which prey on pests that damage crops, and amphibians, which help keep water supplies free from algae.

Herbicides are widely used pesticides that affect plants by changing their chemistry. In doing so, herbicides might also influence the quality of plants as food for herbivores. To study the effects of herbicides on host plant quality, 3 plant species (Plantago lanceolata L., P. major L., and Ranunculus acris L.) were treated with sublethal rates of either a sulfonylurea (Atlantis WG, Bayer CropScience) or a glyphosate (Roundup LB Plus, Monsanto) herbicide, and the development of caterpillars of the cabbage moth Mamestra brassicae L. that fed on these plants was observed.
Of the 6 tested plant–herbicide combinations, 1 combination (R. acris + sulfonylurea herbicide) resulted in significantly lower caterpillar weight, increased time to pupation, and increased overall development time compared with larvae that were fed unsprayed plants. These results might be caused by a lower nutritional value of these host plants or increased concentrations of secondary metabolites that are involved in plant defense. The results of the present and other studies suggest potential risks to herbivores that feed on host plants treated with sublethal rates of herbicides. However, as the effects of herbicides on host plant quality appear to be species-specific and as there are numerous plant–herbicide–herbivore relationships in agricultural landscapes, a general reduction in herbicide contamination of nontarget habitats (e.g., field margins) might mitigate the negative effects of herbicides on host plant quality.