Stephen Jones

Chemicals have been used for decades in order to ensure the growth and survival of crops essential to everyday life, but many of these chemicals are possibly affecting organisms outside of their intended targets, including the bee; an insect essential to the reproduction of various flowering plants. The chemicals scientists believe to be harmful to bees are known as neonicotinoids. These chemicals are synthetic derivatives of the widely used, naturally-occurring pesticide, nicotine.

Bee populations are dramatically on the decline, and scientists are looking for what factors could be responsible for said decline. Dr. Chris Connolly and his colleagues conducted a study at Dundee’s School of Medicine consisting of a sample population of bees, and the conclusion suggests the decline in the bee population is partially due to neonicotinoids. In the study, Dr. Connolly found exposure to low levels of neonicotinoids caused a 55 percent reduction of the live bee population. Dr. Connolly states, “Our research demonstrates beyond doubt that the level of neonicotinoids generally accepted as the average level present in the wild causes brain dysfunction and colonies to perform poorly when consumed by bumblebees.” Even though the pesticides did not kill the bees, the effects of the neurotoxins could still be seen through the examination of the bees’ brains and cells. As mentioned before, the bee population was exposed to low levels of neonicotinoids, resulting in the shutdown of mitochondria, the failure to recognize the scent of a flower, and the inability to remember their way back to the nest.

What is important to remember about the study is the scientists are not suggesting that insect neurotoxins are wholly at fault; but when looking at the results of this study, it is hard not to believe the aforementioned pesticides are not partially to blame. Dr. Connolly’s analysis is only one of many experiments looking into the side-effects of pesticides, and with the number of studies steadily growing; various national governments have started to take action concerning the use of pesticides within the environment. This past September, a US court reversed the Environmental Protection Agency’s approval of the pesticide sulfoxaflor, due to data the court called “flawed and limited.” Although the court denied the use of sulfoxaflor, most neonicotinoids are still approved for use within the US; the situation is the polar opposite in the EU. The EU currently prohibits the use of most neonicotinoids and, as of July, allows the use of sulfoxaflor, even though the European Food Standards Authority believed the lack of information on sulfoxaflor does not exclude the possibility of a negative impact on the already deteriorating bee populations.

The unwanted influence of insect neurotoxins on bees is one of many factors we must look at when examining humans’ usage of chemicals in agriculture, but finding out whether or not these pesticides are significantly hurting bee populations is essential in ensuring the survival of many plant species we rely on every day.

Sources:

http://www.phys.org/news/2015-02-neonicotinoid-insecticides-impair-bee-brains.html

https://www.newscientist.com/article/dn28167-bees-win-as-us-court-rules-against-neonicotinoid-pesticide/