A Florida Fish and Wildlife Conservation Commission aquatic weed control program includes spraying chemical herbicides on Lake Okeechobee. Should Okeechobee Utility Association customers be concerned?

According to Okeechobee Utility Authority Executive Director John Hayford, FWC has notified OUA that its contractors will be spraying near the utility’s water intakes within the next few weeks.

“They were asked to give us a call prior to spraying so that we can switch to the Rim Canal pump station. When they spray, the OUA is planning on sampling before and after and specifically testing for glyphosate,” explained Mr. Hayford.

While Monsanto, the herbicide manufacturer (now owned by Bayer), insists glyphosate is safe, in 2015, the World Health Organization’s International Agency for Research on Cancer declared glyphosate was “probably carcinogenic” to humans.

More recently, researchers documented a link between exposure to glyphosate-based herbicides with an increased risk for non-Hodgkin lymphoma in humans.

“Exposure to Glyphosate-Based Herbicides and Risk for Non-Hodgkin Lymphoma: A Meta-Analysis and Supporting Evidence,” was published in the February 2019 edition of Mutation Research/Reviews in Mutation Research. The report was authored by Luoping Zhang of the Division of Environmental Health Sciences, School of Public Health, University of California Berkeley: Iemaan Rana, Division of Environmental Health Sciences, School of Public Health, University of California Berkeley; Rachel M. Shaffer of the Department of Environmental and Occupational Health Sciences, University of Washington, Seattle; Emanuela Taiolic Institute for Translational Epidemiology and Department of Population Health Science and Policy, Icahn School of Medicine at Mount Sinai, N.Y.; and Lianne Sheppard Department of Environmental and Occupational Health Sciences, University of Washington, Seattle.

“The overall evidence from human, animal and mechanistic studies presented here supports a compelling link between exposures to glyphosate-based herbicides and increased risk for Non-Hodgkin Lymphoma,” the researchers concluded.

This year, however, the United States Environmental Protection Agency reaffirmed its conclusion that glyphosate is “likely not” carcinogenic.

A press release issued April 30, states “the U.S. Environmental Protection Agency (EPA) is taking an important step in the agency’s review of glyphosate. As part of this action, EPA continues to find that there are no risks to public health when glyphosate is used in accordance with its current label and that glyphosate is not a carcinogen. The agency’s scientific findings on human health risk are consistent with the conclusions of science reviews by many other countries and other federal agencies. While the agency did not identify public health risks in the 2017 human health risk assessment, the 2017 ecological assessment did identify ecological risks. To address these risks, EPA is proposing management measures to help farmers target pesticide sprays on the intended pest, protect pollinators, and reduce the problem of weeds becoming resistant to glyphosate.”

“EPA has found no risks to public health from the current registered uses of glyphosate,” said EPA Administrator Andrew Wheeler. “Today’s proposed action includes new management measures that will help farmers use glyphosate in the most effective and efficient way possible, including pollinator protections. We look forward to input from farmers and other stakeholders to ensure that the draft management measures are workable, realistic, and effective.”

Concerns about the health risks from exposure to glyphosate have increased in recent years.
• In April 2018, a former school grounds keeper who is dying of cancer sued Monsanto, alleging his cancer was linked to his exposure to the herbicide. A California jury ordered Monsanto to pay damages of $39 million. The court ordered Monsanto to pay another $250 million for covering up evidence that links glyphosate exposure to cancer.
• In March 2019, another California jury awarded $80 million to another cancer patient, who said he used Roundup products to treat poison oak, overgrowth and weeds on this property for years.
• Monsanto was purchased by Bayer, a German company in June 2019. Bayer is appealing the lawsuit rulings. The company is also facing thousands of similar lawsuits involving agricultural workers, farmers and home gardeners.
• An online search for “glyphosate lawsuits” revealed ads from more than a dozen law firms with class action lawsuits in the works.
• In March 2019 the City of Miami banned the use of glyphosate by city workers and contractors. Also in March, a bill introduced in the U.S. House of Representatives would ban the use of glyphosate on oats before harvest.
Bans or restrictions on the use of the herbicides are increasing worldwide.
• Eight of the 10 provinces of Canada have restrictions on the use of glyphosate. Vancouver has banned the public and private use of the chemical.
• Italy’s Ministry of Health has put restrictions on the use of glyphosate, and restricted the use of the herbicide in areas frequented by the public.
• The Netherlands has banned all non-commercial use of glyphosate.

• In 2017, the European Union voted to end the sale and use of glyphosate by the end of 2022. The push to ban the weed killer used in the brand Roundup came from the environmental organization, Greenpeace EU.
• In January 2019, France banned the sale, distribution and use of Roundup.
• In March 2019, Vietnam announced it has banned the import of glyphosate-based herbicides.

Glyphosate is just one of the chemicals used to control aquatic weeds on Florida lakes, rivers and streams. FWC sprayed 61,532 acres on Florida waterways in fiscal year 2017-2018 at a cost of $17 million, according to the National Pollution Discharge Elimination System (NPDES) report, in 2018, In 2018, FWC spent $23,102 on glyphosate.

In 2018, FWC also spent $58,123 on Diquat and $102,316 on Endothal and Diquat.

According to the Wisconsin Department of Natural Resources Diquat Chemical Fact Sheet: “Diquat is a fast-acting herbicide that works by disrupting cell membranes and interfering with photosynthesis. It is a non-selective herbicide and will kill a wide variety of plants on contact. It does not move throughout the plants, so will only kill parts of the plants that it contacts. Following treatment, plants will die within a week. Diquat will not be effective in lakes or ponds with muddy water or where plants are covered with silt because it is strongly attracted to silt and clay particles in the water. Therefore, bottom sediments must not be disturbed during treatment, such as may occur with an outboard motor. Only partial treatments of ponds or bays should be conducted (1/2 to 1/3 of the water body). If the entire pond were to be treated, the decomposing vegetation may result in very low oxygen levels in the water. This can be lethal to fish and other aquatic organisms. Untreated areas can be treated 10-14 days after the first treatment.

“There are no restrictions on swimming or eating fish from water bodies treated with diquat. Treated water should not be used for drinking water for one to three days, depending on the concentration used in the treatment. Do not use treated water for pet or livestock drinking water for one day following treatment. The irrigation restriction for food crops is five days, and for ornamental plants or lawn/turf, it varies from one to three days depending on the concentration used. The risk of acute exposure to diquat would be primarily to chemical applicators. Diquat causes severe skin and eye irritation and is toxic or fatal if absorbed through the skin, inhaled or swallowed.”

Sources for this story included information from: WeedKillerCrisis.com, Health Impact News and Science Direct.