Insecticides

In the 1950s the commission on food coloring of the German Research Society (DFG), headed by the biochemist Adolf Butenandt and the pharmacologist Hermann Druckrey, represented a policy of preventive risk management in regard to food additives. Druckrey had conducted animal tests with butter yellow, an azo compound used to give butter an attractive yellow colour. These experiments demonstrated that the production of tumours required a certain total dose, regardless of how this was distributed over 35 to 365 days.

Neonicotinoids, a widely used group of pesticides designed to selectively bind to insect nicotinic acetylcholine receptors, were considered relatively safe for mammalian species. However, they have been found to activate vertebrate nicotinic acetylcholine receptors and could be toxic to the mammalian brain.

Twenty-two honeybee (Apis mellifera) colonies were placed in four different cornfield areas in order to study the potential in situ effects of seed-coated systemic neonicotinoid pesticides used in cornfields (Zea mays spp) on honeybee health. Two apiaries were located in two independent neonicotinoid-treated cornfield areas and two others in two independent untreated cornfield areas used as controls. These experimental hives were extensively monitored for their performance and health traits over a period of one year.

Using neonicotinoid insecticides as seed treatments is a common practice in field crop production. Exposure of nontarget organisms to neonicotinoids present in various environmental matrices is debated. In the present study, concentrations of neonicotinoid residues were measured in the top 5 cm of soil and overlying soil surface dust before planting in 25 commercial fields with a history of neonicotinoid seed treatment use in southwestern Ontario in 2013 and 2014 using liquid chromatography–electrospray ionization tandem mass spectrometry.

The widespread use of neonicotinoid insecticides in recent years has led to increasing environmental concern, including impacts to avian populations. In Texas and across their range, Northern Bobwhite (Colinus virginianus; hereafter bobwhite) habitat frequently overlaps with agricultural areas of known neonicotinoid use.

Pregnant women living within one kilometer (0.62 miles) of fields where certain pesticides are applied have children who show a measurable decrease in IQ and verbal comprehension skills by the time they are seven years old, according to a new study by the Center for Environmental Research and Children’s Health at UC Berkeley’s School of Public Health. The study team looked at 283 women and children from the agricultural Salinas Valley enrolled in the long-term Center for the Health of Mothers and Children in Salinas (CHAMACOS) study.

Approximately 95 % of nearly 4 million acres of wetlands located in Iowa’s portion of the Prairie Pothole Region (Des Moines Landform Region) are currently drained and farmed for row-crop agriculture. Many of these wetland basins are too wet to produce consistent crop yields and too dry to function as ecologically intact wetlands. Little information currently exists that documents what, if any value, drained wetlands may have in terms of water quality, wildlife usage and/or habitat, and key hydrological aspects.

Occurrence and removal of six high-production high-volume neonicotinoids was investigated in 13 conventional wastewater treatment plants (WWTPs) and one engineered wetland. Flow-weighted daily composites were analyzed by isotope dilution liquid chromatography tandem mass spectrometry, revealing the occurrence of imidacloprid, acetamiprid, and clothianidin at ng/L concentrations in WWTP influent (60.5 ± 40.0; 2.9 ± 1.9; 149.7 ± 289.5, respectively) and effluent (58.5 ± 29.1; 2.3 ± 1.4; 70.2 ± 121.8, respectively).

Structural and functional responses of a benthic macroinvertebrate assemblage to pulses of the insecticide imidacloprid were assessed in outdoor stream mesocosms. Imidacloprid pulses reduced invertebrate abundance and community diversity in imidacloprid-dosed streams compared to control streams. These results correlated well with effects of imidacloprid on leaf litter decomposition and feeding rates of Pteronarcys comstocki, a stonefly, in artificial streams. Reductions in oxygen consumption of stoneflies exposed to imidacloprid were also observed in laboratory experiments.

Everyone knows not to eat yellow snow. But what about the seemingly harmless, white fluffy stuff? According to research by Claudia Sheedy of the Lethbridge Research Centre, and others, snow is full of pesticides. Sheedy, a research scientist with Agriculture and Agri-Food Canada, was one of several experts who shared their findings from a variety of studies, including the investigation of pesticides in the snowpack. Sheedy said scientists have been studying and finding pesticides in surface water since about 2006, including pesticides that aren’t even used in Canada.