Group presentation on the class of pesticides known as neonicotinoids for BIOL 415.

1. Neonicotinoids
The Busy Bees
Jenn Wolf
Chelsea Jones
Kate Acker
Rene Clark

2. Background
•Class of neuro-active insecticides
• Similar to nicotine
•Newest major class of insecticides
• Only new class that has been developed in the past 3 decades
•Developed in part because of their reduced toxicity in comparison to
organophosphates and carbamates
•Developed from unstable nitromethelane compounds
•The neonicotinoid Imidacloprid is currently the most widely used
insecticide in the world
•Used extensively in agriculture

3. History - Evolution of Insecticides
Chlorinated Hydrocarbons
DDT, Chlorodane, Dieldrin, Mirex
Organophosphates & Carbamates
Dimethoate, Diazinon, Dursban, Orthene
Pyrethroids (synthetic)
Mavrik, Tame, Tempo, Decathlon, Talstar
Reduced-Risk Insecticides
Insect Growth Regulators
Distance, Enstar, Talus NeonicotinoidsNaturalytes
1940-50’s
1960-70’s
1980-90’s
1990-2000’s

4. Mode of Action
• Similar to that of natural nicotine
• Act as antagonists at the
postsynaptic nicotine
acetylcholine receptor (nAChR) in
the central nervous system
•Neonicotinoids bind to the
nAChRs more strongly in insects
than to those of vertebrates
• Selectively more toxic to insects
http://www.pharmahost.org/support/index.php?title=Image:Nicotine_mechanism_
of_action.gif

5. Environmental Impacts
• Neonicotinoids can persist and
accumulate in soils and groundwater
• Varies depending on soil type,
composition, etc.
• Generally non toxic to vertebrates & fish
• Exception: seed-eating vertebrates
(particularly birds)
•Toxic to a variety of non-target, beneficial
insects
• Bees, butterflies, moths
http://www.wildbirdseedmart.com/i/grosbeak_1.jpg

6. Colony Collapse Disorder
• CCD is a phenomenon in which worker bees in
a beehive colony abruptly disappear
• Worldwide massive reduction in bee
populations since 2006
• Increasing in prevalence
• Mechanism and cause remain unclear,
however pesticides are one suggested reason
• Recent research suggests neonicotinoids may
be potentially toxic to honeybees (among
other beneficial insects) even at low levels
http://www.traileraddict.comcontent/unknown/vanishing_bees.jpg

7. Why Do We Care?
•35% of the global crop production depends on
pollinators
• Global crops dependent on honeybee pollination
was estimated to be worth ~$200 billion in 2005
• EX: Squash, berries, and tree fruits
•85% of world’s flowering plants are supported
by pollinators
•Bee shortages have increased the cost of renting
bees for U.S. farmers (up to 20%)
http://media3.s-
nbcnews.com/i/msnbc/Components/Art/HEALTH/0
70502/AP_HONEYBEE_DYING2.gif

8. Regulations
• May 2013: European Commission imposed a number
of restrictions on neonicotinoids
• Restricts use for seed treatment, soil application, and
foliar treatment in crops attractive to bees
• Based on findings in study done by the EFSA on
Clothianidin, Imidacloprid, and Thiamethoxam
• July 2013: The Save American Pollinators Act
introduced in Congress
• Temporarily suspend the use of certain neonicotinoids
• Require study of bee populationsaction.foe.org

9. Current Status
• March 2013: US EPA was sued by a coalition of beekeepers and a
sustainable agriculture advocates
• Accused the agency of performing inadequate toxicity evaluations of neonicotinoids
• Neonicotinoid use is not restricted at all in the U.K. or the U.S.
• But status is currently being re-evaluated by the EPA
• Starting to see resistance in a number of pests
• Particularly in whitefly and Colorado potato beetle populations
• Because of persistence and widespread use

10. References
• European Food Safety Authority. “Conclusion on the Peer Review of the Pesticide Risk Assessment for Bees for the
Active Substance Clothianidin.” EFSA Journal 11.1 (2013): n. pag. Web.
• Oldroyd, Benjamin P. “What’s Killing American Honey Bees?” PLoS Biology 5.6 (2007): E168. Web.
• Whitehorn, P. R., S. O’Connor, F. L. Wackers, and D. Goulson. “Neonicotinoid Pesticide Reduces Bumble Bee Colony
Growth and Queen Production.” Science 336.6079 (2012): 351-52. Web.
• Nauen, R., and I. Denholm. “Resistance of insect pests to neonicotinoid insecticides: Current status and future
prospects.” Archives of Insect Biochemistry and Physiology 58.4 (2005): 200-215. Web.
• Prabhaker, N., S. Castle, T.J. Henneberry, and N.C. Toscano. “Assessment of cross-resistance potential to neonicotinoid
insecticides in Bemisia tabaci.” Bulletin of Entomological Research 95.6 (2005): 535-543. Web.
• Thany, S. H. “Neonicotinoid insecticides: historical evolution and resistance mechanisms.” Advanced Experimental
Medical Biology Journal. 683 (2010): 75-83. Web.
• Kimantas, Janet. “Neonicotinoids.” Alternatives Journal. 39.6 (2013): 11. Web.
• Kleijn, David. "REVIEW: An Overview of the Environmental Risks Posed by Neonicotinoid Insecticides." Ed. Dave
Goulson. Journal of Applied Ecology 50.4 (2013): 977-87.
• Watts, Meryl. "Neonicotinoids." Groundwork.org. Pesticide Action Network, Nov. 2011. Web.
• Fishel, Fredrick M. "Pesticide Toxicity Profile: Neonicotinoid Pesticides1."Ufl.edu. University of Florida, n.d. Web. 23
Apr. 2014. <http://edis.ifas.ufl.edu/pi117>.