Honeybees, bumblebees, and solitary bees are the most important pollinators worldwide, with 35% of the world’s crop production dependent upon them (Blacquière et al. 2012). The declination of the honeybee problem is not just a problem in Canada, it is an issue worldwide. Worker bees are disappearing and not returning to their hives, this is known as colony collapse disorder (CCD) and it results in reduced colony growth and reduced queen production (Girolami et al. 2009; Whitehorn et al. 2012).
In the agricultural industry chemical insecticides are extremely important for crop production; they are responsible for preserving approximately one fifth of our crop yield. Spraying insecticides produces many negative effects such as killing beneficial insects like pollinators. One method to alleviate this problem was to coat the seed with insecticide, such as neonicotinoid, so when the plant germinates and grows the chemical is distributed throughout the entirety of the plant. The goal was to protect the plant from pests that consume the crop tissue, thereby not affecting the pollinators or other beneficial species (Cresswell 2010).
Step 1: Hazard/ Problem Identification:
Neonicotinoids are applied to the surface of the seed and then are distributed throughout the entire plant, giving the plant lasting protection from insects (Girolami et al. 2009; Marzaro et al. 2011). Neonicotinoids pose a risk to many different insects including honeybees, as well as arthropods, birds and smaller mammals (Goulson 2013). Neonicotinoid is registered for use in 120 countries, and for use on over 140 crops (Whitehorn et al. 2012).
Aerial contamination can occur when the seeds are planted and the insecticide can result in being blown into the air (Marzaro et al. 2011). It was found that various concentrations of neonicotinoids are present in guttation drops (drops of xylem sap on the tips or edges of leaves), and in the pollen of these plants with the insecticide seed coats (Girolami et al. 2009; Whitehorn et al. 2012). It was also found that smaller concentrations of neonicotinoids are sometimes present in the pollen of wildflowers which grow in the vicinity of the treated crops (Whitehorn et al. 2012). There are other environmental concerns with neonicotinoids, such as their ability to persist and accumulate in soils, and their hydrophilic properties which enable them to be leached into waterways (Goulson 2013).
Honeybees are exposed to neonicotinoids in various ways. Chemical analysis showed that high quantities (279 ng/bee) of clothianidin (a type of neonicotinoid) were present in the dead bodies of honeybees that had been exposed to dust in the field. This is 10 times higher than the LD50 which is 21.8 ng/bee (Marzaro et al. 2011). Residues of these insecticides are also present at trace levels in plant pollen, nectar, and guttation drops. In Girolami et al. 2009 study it was found that when the...