Assessment of risks to listed species from the use of atrazine in the USA: a perspective

Abstract

Atrazine is a triazine herbicide used predominantly on corn, sorghum, and sugarcane in the US. Its use potentially overlaps with the ranges of listed (threatened and endangered) species. In response to registration review in the context of the Endangered Species Act, we evaluated potential direct and indirect impacts of atrazine on listed species and designated critical habitats. Atrazine has been widely studied, extensive environmental monitoring and toxicity data sets are available, and the spatial and temporal uses on major crops are well characterized. Ranges of listed species are less well-defined, resulting in overly conservative designations of "May Effect". Preferences for habitat and food sources serve to limit exposure among many listed animal species and animals are relatively insensitive. Atrazine does not bioaccumulate, further diminishing exposures among consumers and predators. Because of incomplete exposure pathways, many species can be eliminated from consideration for direct effects. It is toxic to plants, but even sensitive plants tolerate episodic exposures, such as those occurring in flowing waters. Empirical data from long-term monitoring programs and realistic field data on off-target deposition of drift indicate that many other listed species can be removed from consideration because exposures are below conservative toxicity thresholds for direct and indirect effects. Combined with recent mitigation actions by the registrant, this review serves to refine and focus forthcoming listed species assessment efforts for atrazine. Abbreviations: a.i. = Active ingredient (of a pesticide product). AEMP = Atrazine Ecological Monitoring Program. AIMS = Avian Incident Monitoring SystemArach. = Arachnid (spiders and mites). AUC = Area Under the Curve. BE = Biological Evaluation (of potential effects on listed species). BO = Biological Opinion (conclusion of the consultation between USEPA and the Services with respect to potential effects in listed species). CASM = Comprehensive Aquatic System Model. CDL = Crop Data LayerCN = field Curve Number. CRP = Conservation Reserve Program (lands). CTA = Conditioned Taste Avoidance. DAC = Diaminochlorotriazine (a metabolite of atrazine, also known by the acronym DACT). DER = Data Evaluation Record. EC25 = Concentration causing a specified effect in 25% of the tested organisms. EC50 = Concentration causing a specified effect in 50% of the tested organisms. EC50 RGR = Concentration causing a 50% reduction in relative growth rate. ECOS = Environmental Conservation Online System. EDD = Estimated Daily Dose. EEC = Expected Environmental Concentration. EFED = Environmental Fate and Effects Division (of the USEPA). EFSA = European Food Safety Agency. EIIS = Ecological Incident Information System. ERA = Environmental Risk Assessment. ESA = Endangered Species Act. ESU = Evolutionarily Significant UnitsFAR = Field Application RateFIFRA = Federal Insecticide, Fungicide, and Rodenticide Act. FOIA = Freedom of Information Act (request). GSD = Genus Sensitivity Distribution. HC...

Challenges with the current methodology for conducting Endangered Species Act risk assessments for pesticides in the United States

“…As shown in several of the case studies that follow, consideration of other lines of evidence or species-specific information clearly demonstrates that many species deemed LAA by the USEPA for atrazine are, in fact, not at risk from the pesticide. This was also comprehensively demonstrated in the ESA perspective published by Smith et al (2021). Similar results were obtained with the carbamate BEs (USEPA, 2020c, 2020d) and neonicotinoid BEs (USEPA, 2021a(USEPA, , 2021b(USEPA, , 2021c.…”

Exogenous Melatonin Alleviates Atrazine-Induced Glucose Metabolism Disorders in Mice Liver via Suppressing Endoplasmic Reticulum Stress

“…These four groups were the Con group (control), ATZ group (170 mg/kg ATZ), MLT group (5 mg/kg MLT), and ATZ + MLT group (170 mg/kg ATZ + 5 mg/kg MLT). The lethal dose of 50% (LD 50 ) of ATZ in mice is 1750 mg/kg; therefore, a dose of 170 mg/kg ATZ (about 1/10 of the LD 50 ) was chosen as the dose for subchronic treatment in this study . Before weighing, mice were fasted for 1 h to eliminate the effects of food and water on body weight.…”

Versatile Metalloporphyrin‐Based Electrochemical Sensing Applications: From Small Gasotransmitters to Macromolecules

“…Atrazine (ATZ) is an herbicide used predominantly on corn, sorghum, and sugarcane [173] . Although it is currently used in the United States and Australia among other countries, the European Union banned its use in 2003 when elevated levels were found in groundwater [174] .…”

“…Atrazine (ATZ) is an herbicide used predominantly on corn, sorghum, and sugarcane. [173] Although it is currently used in the United States and Australia among other countries, the European Union banned its use in 2003 when elevated levels were found in groundwater. [174] Although there is a general consensus that atrazine is not carcinogenic [175] , there is evidence that it is an endocrine disruptor.…”