Dicamba

AAPCO, 2005

Association of American Pesticide Control Operators,” 2005 Pesticide Drift Enforcement Survey,”  2005.

SUMMARY:

Reports on the results from 2002 and 2003 farmer surveys, including on pesticide drift damage.  FULL TEXT

Abbott, 2017

Chuck Abbott, “Arkansas Task Force Aims for Long-Term Recommendations on Use of Dicamba,” The Fern, August 9, 2017.

SUMMARY:

Arkansas has appointed a 21-member task force to help identify solutions for the dicamba drift damage problem, with 900 complaints received this year so far.  FULL TEXT

Abbott, 2017

Chuck Abbott, “Dicamba is ‘tremendous success,’ says Monsanto; EPA mulls rule change,” FERN’s AG Insider, August 31, 2017.

SUMMARY:

Monsanto claims they will have enough dicamba-resistant seed available for half the U.S. soybean acreage, and chief technology officer Robb Fraley described dicamba as a “tremendous success” for most farmers.  EPA, however, is considering changes ahead of the 2018 season. “We don’t consider this to be normal growing pains for a new technology,” says an EPA official who oversees herbicide regulations.  Monsanto again claims the key is “strict adherence to instructions.” FULL TEXT

American Soybean Association, 2017

American Soybean Association, ” ASA Steps up Urgency in Search for Answers on Dicamba Damage,” ASA News Release,  September 25, 2017.

SUMMARY:

This American Soybean Association (ASA) news release addresses dicamba drift damage, now an issue in 21 of the 30 soybean producing states, and reiterates their support of new formulations since “farmers need and want new technologies to help fight resistant weeds” but call out the “need to ensure that these products can be used by farmers…safely.”  Ron Moore, ASA president and farmer in dicamba-drift affected Illinois is extensively quoted and cites the ASA’s support for independent research at university ag departments in the affected states, and calls for “additional education, applications restrictions, or other actions” to address root causes of the drift problem.  While the problem is mainly stemming from soybeans, Moore recognizes the “good neighbor aspect…ASA has a duty to ensure that we are successfully coexisting with other crops.”  FULL TEXT

Associated Press, 2017a

Associated Press, “Arkansas governor approves board’s limits on dicamba use,” The Washington Times, January 4, 2017.

SUMMARY:

Reports that Gov. Hutchinson has approved the Arkansas State Plant Board’s proposal to limit when and where dicamba can be sprayed in the upcoming planting season.  It includes a requirement for a 1 mile buffer zone before spraying dicamba, except on pasture or rangeland. FULL TEXT

Associated Press, 2017b

Associated Press, “Farm chemical linked to oak damage,” July 2, 2017, Quad-City Times,

SUMMARY:

Reports that almost 1,000 residents of Iowa have contacted the state Department of Natural Resources about damaged leaves on oak trees (photo, right) that looked like insect damage.  Research from the University of Illinois in 2004 showed that herbicide drift was likely linked to the condition, known as leaf tatters, due to exposure to chloroacetanilide herbicides like dicamba.  Exposure occurs from direct drift but also through atmospheric volubility in areas not close to where the herbicide was applied. White oaks are particularly susceptible, and trees can die if damage to the leaves occurs over multiple years.   FULL TEXT

Band et al., 2011

Band PR, Abanto Z, Bert J, Lang B, Fang R, Gallagher RP, Le ND., “Prostate cancer risk and exposure to pesticides in British Columbia farmers,” Prostate, 2011, 71:2, DOI: 10.1002/pros.21232.

ABSTRACT:

BACKGROUND: Several epidemiologic studies have reported an increased risk of prostate cancer among farmers. Our aim was to assess the risk of developing prostate cancer in relation to exposure to specific active compounds in pesticides.

METHOD: A case-control approach was used with 1,516 prostate cancer patients and 4,994 age-matched internal controls consisting of all other cancer sites excluding lung cancer and cancers of unknown primary site. Lifetime occupational history was obtained through a self-administered questionnaire and used in conjunction with a job exposure matrix to estimate the participants’ lifetime cumulative exposure to approximately 180 active compounds in pesticides. Conditional logistic regression was used to assess prostate cancer risk, adjusting for potential confounding variables and effect modifiers. These include age, ethnicity, alcohol consumption, smoking, education, and proxy respondent.

RESULTS AND CONCLUSIONS: The significant association between prostate cancer risk and exposure to DDT (OR = 1.68; 95% CI: 1.04-2.70 for high exposure), simazine (OR = 1.89; 95% CI: 1.08-3.33 for high exposure), and lindane (OR = 2.02; 95% CI: 1.15-3.55 for high exposure) is in keeping with those previously reported in the literature. We also observed a significant excess risk for several active ingredients that have not been previously reported in the literature such as dichlone, dinoseb amine, malathion, endosulfan, 2,4-D, 2,4-DB, and carbaryl. Some findings in our study were not consistent with those reported in the literature, including captan, dicamba, and diazinon. It is possible that these findings showed a real association and the inconsistencies reflected differences of characteristics between study populations.

Barber, 2017

Tom Barber, “Dicamba Drift and Potential Effects on Soybean Yield,” AGWatch Network, July 7, 2016.

SUMMARY:

Tom Barber, an Extension Weed Scientist at the University of Arkansas, posts a chilling overview of what he has observed in soybean fields in several parts of the state. His piece “Dicamba Drift and Potential Effects on Soybean Yield” contains an ominous warning – “We have observed a 10% [soybean] yield loss from dicamba at rates as low as 1/1024X of the labeled rate” – a very low level of drift and/or movement following volatilization.  Barber also warns that low rates of dicamba drift/movement onto soybeans, especially later in the crop’s growth cycle (i.e. R3-R5) can result in carryover of dicamba in the seed…triggering problems if the soybeans are used for seed in the next year and increasing dietary exposure levels.  FULL TEXT

BASF, 1985

BASF, Marksman Herbicide Label, September 9, 1985, EPA Registration Number: 876-451.

SUMMARY:

Early label for Marksman herbicide with dicamba plus atrazine.  FULL TEXT

BASF, 1992

BASF, Clarity Herbicide Label, July 23, 1992, EPA Registration Number: 55947-46.

SUMMARY:

Early label for Clarity Herbicide containing the diglycolamine (DGA) form of dicamba.  FULL TEXT