Betsy Jibben, “Farmers Waiting for EPA Approval of Dicamba,” AgWeb, November 7, 2016.
SUMMARY:
A mess was created in 2016 when Monsanto began selling its dicamba-tolerant Xtend soybeans before the herbicide designed to use with the GE seeds was approved by the EPA. Farmers bought the seed anyway because of its high yield. Some farmers sprayed dicamba anyways, an illegal off-label use, resulting in 40,000 acres of damage from drift in Missouri alone. FULL TEXT
Marci Manley, “AR Man Shot Dead in Farm Dispute,” KARK NBC 4 News Broadcast, October 28, 2016, posted at www.arkansasmatters.com,
SUMMARY:
In a shocking turn of events, farmer-to-farmer conflict over dicamba drift from off-label herbicide use ended in murder when a man was shot during a meeting about damaged crops. FULL TEXT
Dan Charles, “How Monsanto And Scofflaw Farmers Hurt Soybeans In Arkansas, ” NPR, August 1, 2016.
SUMMARY:
NPR story describes the illegal spraying of dicamba on soybean fields in Arkansas where Monsanto began selling its Xtend dicamba-resistant soybeans before the EPA had approved the new dicamba herbicide formulation for use with the GE seeds. Monsanto said farmers wanted the seed anyway because of higher yields, but many chose to illegally spray older dicamba formulations that were prone to drift. FULL TEXT
Elisabeth A. Scribner, William A. Battaglin, Robert J. Gilliom, and Michael T. Meyer, “Concentrations of Glyphosate, Its Degradation Product, Aminomethylphosphonic Acid, and Glufosinate in Ground- and Surface-Water, Rainfall, and Soil Samples Collected in the United States, 2001-06,” August 2007, United States Geological Service.
ABSTRACT:
The U.S. Geological Survey conducted a number of studies from 2001 through 2006 to investigate and document the occurrence, fate, and transport of glyphosate, its degradation product, aminomethylphosphonic acid (AMPA), and glufosinate in 2,135 ground- and surface-water samples, 14 rainfall samples, and 193 soil samples. Analytical methods were developed to detect and measure glyphosate, AMPA, and glufosinate in water, rainfall, and soil. Results show that AMPA was detected more frequently and occurred at similar or higher concentrations than the parent compound, glyphosate, whereas glufosinate was seldom found in the environment. Glyphosate and AMPA were detected more frequently in surface water than in ground water. Trace levels of glyphosate and AMPA may persist in the soil from year to year. The methods and data described in this report are useful to researchers and regulators interested in the occurrence, fate, and transport of glyphosate and AMPA in the environment. FULL TEXT
Laís de Brito Rodrigues, Rhaul de Oliveira , Flávia Renata Abe, Lara Barroso Brito, Diego Sousa Moura, Marize Campos Valadares, Cesar Koppe Grisolia, Danielle Palma de Oliveria, and Gisele Augusto Rodrigues de Oliveira, “Ecotoxicological Assessment of Glyphosate-Based Herbicides,” Environmental Toxicology and Chemistry, 2017, 36:7, DOI: 10.1002/etc.3580.
ABSTRACT:
Glyphosate-based herbicides are the most commonly used worldwide because they are effective and relatively nontoxic to nontarget species. Unlimited and uncontrolled use of such pesticides can have serious consequences for human health and ecological balance. The present study evaluated the acute toxicity and genotoxicity of 2 glyphosate-based formulations, Roundup Original (Roundup) and Glyphosate AKB 480 (AKB), on different organisms: cucumber (Cucumis sativus), lettuce (Lactuca sativa), and tomato (Lycopersicon esculentum) seeds, and microcrustacean Artemia salina and zebrafish (Danio rerio) early life stages. For the germination endpoint, only L. esculentum presented significant sensitivity to AKB and L. sativa to Roundup, whereas both formulations significantly inhibited the root growth of all species tested. Both AKB and Roundup induced significant toxicity to A. salina; both are classified as category 3, which indicates a hazard for the aquatic environment, according to criteria of the Globally Harmonized Classification System. However, Roundup was more toxic than AKB, with 48-h median lethal concentration (LC50) values of 14.19 mg/L and 37.53 mg/L, respectively. For the embryo–larval toxicity test, Roundup proved more toxic than AKB for the mortality endpoint (96-h LC50 values of 10.17 mg/L and 27.13 mg/L, respectively), whereas for the hatching parameter, AKB was more toxic than Roundup. No significant genotoxicity to zebrafish larvae was found. We concluded that AKB and Roundup glyphosate-based formulations are phytotoxic and induce toxic effects in nontarget organisms such as A. salina and zebrafish early life stages. FULL TEXT
Ariena H.C. van Bruggen, Max Teplitski, Volker Mai, Kwang Cheol Jeong, Joan D. Flocks, Maria R. Finckh, and J. Glenn Morris, Jr., “Environmental and health effects of the herbicide glyphosate,” 2018, Science of the Total Environment, 2018, 616-617, DOI: 10.1016/j.scitotenv.2017.10.309.
ABSTRACT:
BACKGROUND: The WHO reclassified the herbicide glyphosate as probably carcinogenic to humans, and concerns about potential side effects of the large-scale use of glyphosate have increased. We are interested in potential indirect effects of glyphosate on animal, human and plant health due to shifts in microbial community composition and antibiotic resistance in soil, plant surfaces and intestinal tracts.
OBJECTIVES: We review the scientific literature on glyphosate use, its toxicity to macro- and microorganisms, effects on microbial compositions, and potential indirect effects on plant, animal and human health. We hypothesize that glyphosate use has increased antibiotic resistance and propose study designs for testing this hypothesis.
DISCUSSION: Although the acute toxic effects of glyphosate on mammals are low, the chronic effects on human and animal health could be considerable due to accumulation in the environment. Intensive glyphosate use has led to the selection of glyphosate-resistant weeds and microorganisms. Shifts in microbial compositions due to selective pressure by glyphosate may have contributed to the proliferation of pathogens. Research on a link between glyphosate and antibiotic resistance is scarce. We hypothesize that the selection pressure for glyphosate resistance in bacteria could lead to shifts in microbiome composition and increases in antibiotic resistance.
CONCLUSION: We recommend interdisciplinary research on the associations between glyphosate use, distortions in microbial communities, expansion of antibiotic resistance and the emergence of animal, human and plant diseases. Independent research is needed to revisit the tolerance thresholds for glyphosate residues in food and animal feed taking all possible health risks into account. FULL TEXT
Norma Casabé, Lucas Piola, Julio Fuchs, María Luisa Oneto, Laura Pamparato, Silvana Basack, Rosana Giménez, Rubén Massaro, Juan C. Papa and Eva Kesten, “Ecotoxicological Assessment of the Effects of Glyphosate and Chlorpyrifos in an Argentine Soya Field,” Journal of Soils and Sediment, 2007, DOI: 10.1065/JSS2007.04.224.
ABSTRACT:
BACKGROUND, AIM, AND SCOPE: Continuous application of pesticides may pollute soils and affect non-target organisms. Soil is a complex ecosystem; its components can modulate the effects of pesticides. Therefore, it is recommended to evaluate the potential environmental risk of these compounds in local conditions. We performed an integrated field-laboratory study on an Argentine soya field sprayed with glyphosate and chlorpyrifos under controlled conditions. Our aim was to compare the sensitivity of a series of endpoints for the assessment of adverse effects of the extensive use of these agrochemicals.
MATERIALS AND METHODS: A RR soya field in a traditional farming area of Argentina was sprayed with glyphosate (GLY) or chlorpyrifos (CPF) formulations at the commercially recommended rates, according to a randomized complete block design with 3 replicates. In laboratory assays, Eisenia fetida andrei were exposed to soil samples (0–10 cm depth) collected between the rows of soya. Endpoints linked to behavior and biological activity (reproduction, avoidance behavior and bait-lamina tests) and cellular/subcellular assays (Neutral Red Retention Time –NRRT; DNA damage – Comet assay) were tested. Field assays included litterbag and bait-lamina tests. Physico/chemical analyses were performed on soil samples.
RESULTS: GLY reduced cocoon viability, decreasing the number of juveniles. Moreover, earthworms avoided soils treated with GLY. No effects on either reproduction or on avoidance were observed at the very low CPF concentration measured in the soils sampled 10 days after treatment. Both pesticides caused a reduction in the feeding activity under laboratory and field conditions. NRRT was responsive to formulations of CPF and GLY. Comet assay showed significantly increased DNA damage in earthworms exposed to CPF treated soils. No significant differences in DNA migration were observed with GLY treated soils. Litterbag field assay showed no differences between treated and control plots. DISCUSSION: The ecotoxicological effects of pesticides can be assessed by monitoring the status of communities in real ecosystems or through the use of laboratory toxicity tests. Litterbag field test showed no influence of the treatments on the organic matter breakdown, suggesting a scarce contribution of soil macrofauna. The bait-lamina test, however, seemed to be useful for detecting the effects of GLY and CPF treatments on the activity of the soil fauna. CPF failed to give significant differences with the controls in the reproduction test and the results were not conclusive in the avoidance test. Although the field population density of earthworms could be affected by multiple factors, the effects observed on the reproduction and avoidance tests caused by GLY could contribute to its decrease, with the subsequent loss of their beneficial functions. Biomarkers measuring effects on suborganism level could be useful to predict adverse effects on soil organisms and populations. Among them, NRRT, a lysosomal destabilization biomarker, resulted in demonstrating more sensitivity than the reproduction and avoidance tests. The Comet assay was responsive only to CPF. Since DNA damage can have severe consequences on populations, it could be regarded as an important indicator to be used in the assessment of soil health.
CONCLUSIONS: Reproduction and avoidance tests were sensitive indicators of GLY exposure, with the former being more labor intensive. Bait-lamina test was sensitive to both CPF and GLY. NRRT and Comet assays revealed alterations at a subcellular level, and could be considered complementary to the biological activity tests. Because of their simplicity, some of these bioassays seemed to be appropriate pre-screening tests, prior to more extensive and invasive testing.
RECOMMENDATIONS AND PERSPECTIVES: This study showed deleterious effects of GLY and CPF formulations when applied at the nominal concentrations recommended for soya crops. Further validation is needed before these endpoints could be used as field monitoring tools in Argentine soya soils (ecotoxicological risk assessment – ERA tools). FULL TEXT
“Tennessee Dept. of Agriculture issues new measures for Dicamba,” July 12, 2017, Winchester Herald Chronicle.
SUMMARY:
The Tennessee Department of Agriculture responded to increased farmer-to-farmer complaints of damage from dicamba drift by enacting new rules on dicamba use in the state. The rules include requiring special licensing and record keeping for applicators, banning the use of older formulations for the rest of the season, and limiting the timing that it can be applied, and will be effective through October 1, 2017. FULL TEXT
Gil Gullickson, “Why Dicamba-Tolerant Soybean Technology is in Trouble,” July 11, 2017, Successful Farming,
SUMMARY:
This article reports on dicamba drift in Missouri, where damage to date is tallied at 203,045 acres on soybeans, as well as over 6,500 acres of other crops and gardens, including certified organic vegetable farms. The damage appears to be caused both by known problems with how and when dicamba is sprayed, and also by greater than expected damage from legal and correct dicamba spraying of the newest varieties that are supposed to be low volatility: BASF’s Engenia, Dupont FeXapan Plus Vapor Grip Technology, and Monsanto’s Xtendimax with Vapor Grip Technology. In response the Missouri Department of Agriculture voted on July 7, 2017 to temporarily suspend all sales and applications of dicamba. FULL TEXT
Sonja Begemann and Susan Skiles Luke, July 10, 2017, “Arkansas, Missouri Ban Dicamba,” AgWeb.
SUMMARY:
Effective just after midnight on July 11, Arkansas finalizes a 120-day emergency ban on dicamba sales and use. Missouri also banned dicamba the week before, with the intent of re-opening sales once the investigation into complaints of damage from dicamba drift is complete. The Missouri Soybean Association is quoted as saying that more than 200,000 acres of soybeans are affected in the state. In a statement, Monsanto stressed the importance of “following label and local requirements” for their Roundup Ready Xtend Crop System of dicamba-resistant soybeans. The article lists the number of complaints of dicamba damage in Arkansas as “nearly 600,” up from the 500 reported on July 6, 2017. FULL TEXT