13
Jul
California to List Atrazine and Other Triazine Weedkillers to Prop 65 as Reproductive Toxicants
(Beyond Pesticides, July 13, 2016) California’s Office of Environmental Health Hazard Assessment (OEHHA) has announced that atrazine, its chemical cousins, propazine, simazine, and its break down triazine compounds des-ethyl atrazine (DEA), des-isopropyl atrazine (DIA) and 2,4-diamino-6-chloro-s-triazine (DACT) would be added to the list of chemicals known to the state to cause reproductive toxicity for purposes of the state’s Proposition 65. The formal listing has been delayed and will not be effective until July 15, 2016 due to litigation from the manufacturer, Syngenta, which opposes the listing.
In 2014 the state announced its Notice of Intent to list the triazines: atrazine, propazine, simazine and their breakdown products under Proposition 65 — the state’s law on toxic chemicals. The listing of these chemicals was initially to be effective on August 3, 2015. However, Syngenta, manufacturer of atrazine, challenged the listing decision, leading to a delay in the formal decision. Syngenta Crop Protection v OEHHA (Sacramento Superior Court case#34-2014-800001868). Syngenta’s challenge was unsuccessful and now the official listing can move forward, in spite of Syngenta’s pending appeal. The six chemicals will now be known as reproductive toxicants in the state of California effective July 15, 2016. See listing notice. http://oehha.ca.gov/media/downloads/crnr/listingnoticetriazines070516.pdf
Proposition 65, officially known as the Safe Drinking Water and Toxic Enforcement Act of 1986, was enacted as a ballot initiative in November 1986. The proposition protects the state’s drinking water sources from being contaminated with chemicals known to cause cancer, birth defects or other reproductive harm, and requires businesses to inform Californians about exposures to such chemicals.
According to OEHHA, the determination to list atrazine and the other triazines is based on the findings of several previous U.S. Environmental Protection Agency (EPA) documents which conclude that they cause developmental and reproductive effects through a common mechanism of toxic action. Some of these cited EPA documents include, ”˜Triazine Cumulative Risk’ (2006); 2006 Decision Documents for Atrazine, ”˜Reregistration Eligibility Decision Document for Simazine’ (2006) and ”˜Propazine: Revised HED [Health Effects Division] Risk Assessment for the Tolerance Reassessment Eligibility Decision Document’ (2005). Further, EPA established several reference doses (maximum acceptable oral dose) on the basis of reproductive and developmental toxicity, relying on endpoints that included impacts on the endocrine system and physical malformations.
Specifically, 2006 EPA’s Cumulative Risk Assessment on the triazines states, “The underlying mechanism of the endocrine-related changes associated with atrazine and similar triazines is understood to involve a disruption of the hypothalamic-pituitary-gonadal (HPG) axis”¦ In particular, the triazine-mediated changes in the HPG relating to neuroendocrine and neuroendocrine-related developmental and reproductive toxicity are considered relevant to humans, and these adverse effects were identified as endpoints for the exposure scenarios selected for consideration in the quantitative cumulative assessment.” (p. 4) OEHHA explains that based on the evidence reviewed from EPA’s findings the requirements for Prop 65 listing have been met.
California’s Prop. 65 is the only law in the nation to prohibit businesses from knowingly and intentionally exposing consumers to a chemical known to the state to cause cancer or reproductive harm without first providing a warning. Violations are subject to potential penalties of up to $2,500 per day for each violation, and each sale can constitute a violation. Prevailing plaintiffs can also recover their attorneys’ fees.
In addition to atrazine and its cousin’s impact on human health, their impact on environmental health is also well documented. Just last month EPA released its triazine ecological risk assessment, which found that these chemicals pose risks to fish, amphibians, aquatic invertebrates, and even birds, reptiles and mammals. The assessments evaluated risks to animals and plants including, amphibians, birds, mammals, fish, reptiles, aquatic invertebrates, aquatic plant communities, and terrestrial plants. For atrazine, EPA concludes, “aquatic plant communities are impacted in many areas where atrazine use is heaviest, and there is potential chronic risks to fish, amphibians, and aquatic invertebrate in these same locations. In the terrestrial environment, there are risk concerns for mammals, birds, reptiles, plants and plant communities across the country for many of the atrazine uses.” Levels of concerns were exceeded by as much as 200-fold for some organisms! When it comes to amphibians, impacts which have been extensively documented by researchers like Tyrone Hayes, PhD, at the University of California, Berkeley, EPA finds that “there is potential for chronic risks to amphibians based on multiple effects endpoint concentrations compared to measured and predicted surface water concentrations.” Previous scientific reviews, like the 2009 analysis of more than 100 scientific studies conducted on atrazine, found evidence that atrazine harms fish and frogs. All three chemicals are mobile and persistent in the environment, which results in water contamination. According to the U.S. Geological Survey (USGS), atrazine is one of the most frequently detected pesticides, found at concentrations at or above aquatic benchmarks, and is also frequently detected in shallow ground water.
Studies by Dr. Hayes and others have shown that concentrations as little as 0.1ppb impact hormone function in organisms and turns tadpoles into hermaphrodites — creatures with both male and female sexual characteristics. Research also finds that atrazine interferes with mammary gland development in the breast of mammals and is linked to certain birth defects like gastroschisis and choanal atresia, which are significantly increased for pregnant women with high levels of atrazine exposure in agricultural areas, and in urban streams.
EPA is currently in the registration review process for these chemicals, and the draft ecological assessments are now open for public comment until August 5, 2016. EPA will have atrazine’s assessment peer reviewed by the Scientific Advisory Panel in 2017. Submit your comments for Atrazine (EPA-HQ-OPP-2013-0266), Simazine (EPA-HQ-OPP-2013-0251) and Propazine (EPA-HQ-OPP-2013-0250) by October 4, 2016 at the federal docket. https://www.regulations.gov/comment?D=EPA-HQ-OPP-2015-0794-0005
All unattributed positions and opinions in this piece are those of Beyond Pesticides.
Source: OEHHA
