Since 1945, the use of pesticides has risen 3,300 percent, however crop loss due to pests has not decreased. Despite the fact that USA (on average) uses 2.2 billion pounds of pesticides annually, crop loss has increased by 20 percent. To make matters worse these statistics were taken a decade ago, and if you remember anything from your high school biology class, pests evolve and adapt swiftly to the new environment. Now, with tougher pests you need stronger chemicals, and the vicious cycle continues. Since there is a high demand for these pesticides, hundreds of thousands of chemicals are produced (yearly) and they have to be screened by the EPA. Theoretically, this is what EPA should do and would like to do. However, unfortunately their major back-logs and a continuous stream of chemicals are constantly being pushed by respective firms thus creating a loop hole where a couple of hundred chemicals make it to the market without ‘intensive’ screening -- among them are several neonicotinoids.
|Photo: taken from the ACS 'molecule of the week.' Clothianidin-|
One of the first neonicotinoids to make it to the market was Clothianidin. This insecticide was jointly developed by Bayer and Takeda Chemical Industries to replace nicotine (as an insecticide). As a Side note, nicotine was thought of to be a good insecticide, however it degrades too quickly thereby not practical in large scale production. In general neonicotinoids have an affinity for nicotinic acetylcholine receptors which are in control of sodium channels responsible for cell signaling. These neural receptors bind with the neonicotinoid which results in paralysis and death in insects – no cell signaling, no movement. Since there were massive domino effects on bees and other organisms, several neonicotinoids have been issued a 2-year ban for further investigation.
Due to the wide-spread usage here in the USA, bee populations are are already feeling the heat.In a memorandum to federal agencies Obama ordered the EPA to assess the impact of all pesticides, on pollinator health with a deadline of 180 days. EPA has started the assessment, which now has a deadline. There are environmental advocacy groups pressuring EPA to ban neonicotinoids because of its impact on bees. Larissa Walker, head of the pollinator campaign at the Center for Food and Safety says, “The White House announcement is on the right track, but assessment and habitat building alone won’t save our pollinators.” What do you think will come about this?
-Quote taken from C&EN article “The White House and Bees.”
Michael (Mykola) Schur
Chemical Engineering student at Calvin College