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Atrazine and Amphibians: A Story of Profits, Controversy, and Animus

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Abstract

The herbicide atrazine is one of the most commonly used, well studied, and controversial pesticides on the planet. Much of the controversy surrounds the effects of atrazine on wildlife, particularly amphibians, and involves representatives from Syngenta Crop Protection, Inc., the company that produces atrazine, the US Environmental Protection Agency, and several academics with current, past, or no associations with Syngenta. Here, I briefly review the effects of atrazine on amphibians and provide a timeline of some of the most salient events in the history of the atrazine-amphibian controversy.
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... Despite the USEPA concluding in 2016 that atrazine poses risks to aquatic plants, fish, amphibians, mammals, birds, and reptiles (Farruggia et al. 2016), and in 2018, that it poses reproductive and developmental risks to humans, particularly children (US Environmental Protection Agency 2018), in 2020, the USEPA renewed the registration of atrazine and relaxed regulations, allowing 50% more atrazine to enter water bodies (Erickson 2019; US Environmental Protection Agency 2020). Although the story of atrazine has been partially told (Rohr 2018), these recent regulatory events, the Trump administration's regular dismissal of science (Lin 2019), and the change in the United States presidency, underscore the importance of drawing new attention to this remarkable story in the history of toxicology that is unfamiliar to so many. Hence, I provide a more complete and updated account of the most salient moments in the history of the atrazine controversy, emphasizing bent science and how it might have impacted decision making with potential consequences for ecosystem and human health and public trust in science. ...
... I focus predominantly on the effects of atrazine on amphibians because most of the controversy surrounding atrazine has centered on amphibian studies. Atrazine is documented to affect amphibian growth and timing of metamorphosis, (Larson et al. 1998;Karasov 2000, 2001;Boone and James 2003;Rohr et al. 2004;Storfer 2006a, 2006b) behaviors crucial for foraging and avoiding predators, (Rohr et al. 2003(Rohr et al. , 2004 and desiccation (Rohr andPalmer 2005, 2013). Moreover, delayed or persistent effects of atrazine on behavior and physiology can increase mortality risk (Storrs and Kiesecker 2004;Rohr and McCoy 2010b;Rohr andPalmer 2005, 2013). ...
... Atrazine is documented to affect amphibian growth and timing of metamorphosis, (Larson et al. 1998;Karasov 2000, 2001;Boone and James 2003;Rohr et al. 2004;Storfer 2006a, 2006b) behaviors crucial for foraging and avoiding predators, (Rohr et al. 2003(Rohr et al. , 2004 and desiccation (Rohr andPalmer 2005, 2013). Moreover, delayed or persistent effects of atrazine on behavior and physiology can increase mortality risk (Storrs and Kiesecker 2004;Rohr and McCoy 2010b;Rohr andPalmer 2005, 2013). There have been numerous studies on the effects of atrazine on physiology because of the role of physiology to vertebrate survival and conservation (Martin et al. 2010;Rohr et al. 2013b;Madliger et al. 2016). ...
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The herbicide atrazine is one of the most commonly used, well studied, and controversial pesticides on the planet. Much of the controversy involves the effects of atrazine on wildlife, particularly amphibians, and the ethically questionable decision making of members of industry, government, the legal system, and institutions of higher education, in most cases in an effort to “bend science,” defined as manipulating research to advance economic, political, or ideological ends. In this Critical Perspective I provide a timeline of the most salient events in the history of the atrazine saga, which includes a multimillion‐dollar smear campaign, lawsuits, investigative reporting, accusation of impropriety against the US Environmental Protection Agency, and a multibillion‐dollar transaction. I argue that the atrazine controversy must be more than just a true story of cover‐ups, bias, and vengeance. It must be used as an example of how manufacturing uncertainty and bending science can be exploited to delay undesired regulatory decisions and how greed and conflicts of interest—situations where personal or organizational considerations have compromised or biased professional judgment and objectivity—can affect environmental and public health and erode trust in the discipline of toxicology, science in general, and the honorable functioning of societies. Most importantly, I offer several recommendations that should help to 1) prevent the history of atrazine from repeating itself, 2) enhance the credibility and integrity of science, and 3) enrich human and environmental health. Environ Toxicol Chem 2021;00:1–15.
... Despite the plethora of controversies surrounding the toxicity of atrazine based herbicides on non-target organisms such as amphibians [26], they have been proven to have non-target effects on animals [15,27]. For example, atrazine based herbicides are known to alter reproductive processes and development in insects, amphibians, fish, reptiles, birds, rodents and goats [15,16,[28][29][30] Vogel et al. [15] reported that exposure to atrazine had significant effects on males of Drosophila melanogaster Meigen (Diptera: Drosophilidae) mating ability and the number of eggs his partner laid when he was successful at mating. ...
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... Despite the plethora of controversies surrounding the toxicity of atrazine based herbicides on non-target organisms such as amphibians [26], they have been proven to have non-target effects on animals [15,27]. For example, atrazine based herbicides are known to alter reproductive processes and development in insects, amphibians, fish, reptiles, birds, rodents and goats [15,16,[28][29][30] Vogel et al. [15] reported that exposure to atrazine had significant effects on males of Drosophila melanogaster Meigen (Diptera: Drosophilidae) mating ability and the number of eggs his partner laid when he was successful at mating. ...
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... Atrazine has been reported to interfere with physiological and biochemical systems in the nontarget aquatic organisms, affecting functions such as development, reproduction, and survival of aquatic biota (Nwani et al., 2010;Rohr and McCoy, 2010). These effects corroborate the reports on extreme population declines in Piscean and amphibian communities (Hayes et al., 2006;Hayes et al., 2010;Rohr, 2013). Atrazine has also been reported to bio-accumulate in various organ tissues (Xing et al., 2012;Dornelles and Oliveira, 2014;Singh et al., 2017). ...
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