NCC Comments to EPA Regarding Dimethoate

In response to EPA's Sept. 25, 2015 Federal Register notice opening a public comment period on EPA’s draft human health and ecological risk assessments for the registration review of a group of 35 different pesticides known as sulfonylureas and other identified chemicals, the NCC provided comments urging the agency to retain all labeled uses of dimethoate for control of cotton pests.

Published: February 24, 2016
Updated: February 24, 2016

February 23, 2016

OPP Docket
Environmental Protection Agency Docket Center (EPA/DC), (28221T)
1200 Pennsylvania Ave. NW
Washington, DC 20460-0001

Ms. Kelly Ballard, Re-Evaluation Division (7508P)
Office of Pesticide Programs
Environmental Protection Agency
1200 Pennsylvania Ave. NW,
Washington, DC 20460–0001

Re: Docket ID No. EPA–HQ–OPP–2009-0059.

Dear Ms. Ballard:
In response to the Environmental Protection Agency’s (EPA) September 25, 2015 Federal Register notice opening a public comment period on EPA’s draft human health and ecological risk assessments for the registration review of a group of 35 different pesticides known as sulfonylureas and other identified chemicals, the National Cotton Council (NCC) appreciates the opportunity to provide the following comments related to the importance of the pesticide dimethoate as an insect management product.
The NCC is the central organization of the United States cotton industry.  Its members include producers, ginners, cottonseed processors and merchandizers, merchants, cooperatives, warehousers and textile manufacturers.  A majority of the industry is concentrated in 17 cotton-producing states stretching from Virginia to California. The NCC represents producers who cultivate between 10 and 14 million acres of cotton.  Annual cotton production, averaging approximately 16 to 20 million 480-lb bales, is valued at more than $5 billion at the farm gate.  The downstream manufacturers of cotton apparel and home furnishings are located in virtually every state. Farms and businesses directly involved in the production, distribution and processing of cotton employ more than 230,000 workers and produce direct business revenue of more than $27 billion.  Accounting for the ripple effect of cotton through the broader economy, direct and indirect employment surpasses 420,000 workers with economic activity well in excess of $120 billion. In addition to the cotton fiber, cottonseed products are used for livestock feed, and cottonseed oil is used as an ingredient in food products as well as being a premium cooking oil.

The NCC urges EPA to recognize that the benefits of dimethoate as a crop protection tool for cotton are not reflected in its volume of use.  Dimethoate provides producers with an alternate chemistry to incorporate into their Integrated Pest Management (IPM) and resistance management programs targeting cotton insect pests, particularly cotton fleahoppers, fleabeetles, stinkbugs, and thrips.  Without the product, producers will be forced to rely more heavily on only a few other alternatives, particularly neonicotinoid chemistries, to control piercing sucking insect pests.  The NCC urges EPA to recognize the value of resistance management and the need for multiple modes of action (MOA) to preserve products that provide control of insect pests.  Additionally, the NCC urges EPA to understand that many of these insect pests are not treated on a routine basis, but occasionally exceed threshold levels in some fields and require intervention with crop protection chemistries.  Even within a specific geographic area, some of these pests may only exceed thresholds in a small fraction of the fields, but it is critical to have an effective control product available to fill the niche created by these isolated needs.

The NCC is aware of the September 15, 2015 memo claiming justification to include a 10X Food Quality Protection Act (FQPA) safety factor for risk assessment of all organophosphates.  The determination to include the safety factor represents a major policy change, but did not engage stakeholders in a public notice and comment procedure, thereby eliminating transparency.  Simultaneously, EPA released “Pesticide Registration Review; Draft Human Health and Ecological Risk Assessments for Sulfonylureas and Certain other Pesticides; Notice of Availability and Request for Comments” on September 25, 2015 (EPA-HQ-OPP-2015-0386).  The notice announced draft human health risk assessments for some 35 various chemicals, with several, but not all, organophosphate chemicals listed among numerous Sulfonylureas and other pesticides including some insect growth regulators.  The Agency identifies some ecological risk assessments that were conducted as group assessments and separate human health risk assessments.  Although the Notice stated that comments could be submitted to the docket identified by EPA-HQ-OPP-2015-0386, the NCC was later instructed that comments were to be submitted individually to single dockets.  The NCC has submitted comments to several dockets, but expresses to the Agency that the announcement created confusion about what was grouped, what was not grouped, could comments be submitted to the one notice of the 35 chemicals or were commenters to locate the individual dockets in order to comment separately.  The Notice format with the 35 chemicals, not all of a similar chemical group, some ecological risk assessments for similar chemicals grouped, health assessments not grouped, and no single holding site for the materials contained in the notice of the 35 chemicals created confusion and difficulty in locating and understanding what the Agency was doing.

Upon locating the various human health risk assessments for the organophosphate (OP) pesticides, it was clear the agency had already conducted the health risk assessment with the inclusion of the 10X FQPA safety factor referred to in the September 15, 2015 Memo.  It is also very clear from page 2 of the memo that the use of this safety factor will greatly impact the risk assessment of many extremely valuable, if not critical, pesticide products of agriculture.  It is also clear that the Agency released some of the OP human health risk assessments in the notice of 35 – which again were not all related chemistries – but did not release all of the OP risk assessments.  However, EPA identified a list of the organophosphate chemicals on page 2 of the Sept. 15 memo.  The list contains approximately 8 different active ingredients used in cotton.  The uses are predominantly defoliation for harvest and insect control.  Not all of these eight were identified in the EPA notice of the 35 chemicals, but it is NCC’s concern that action taken on the chemicals contained in the notice will set the precedent for all future review of OP’s.

The EPA’s argument for including the 10X safety factor relies predominately on an epidemiology study conducted at Columbia University.  The Agency notes other studies that suggest associations and speaks of correlations of various studies, but the agency knows well that correlations do not demonstrate cause and can easily be flawed by the inclusion of inappropriate variables or omission of relevant variables.  Many examples have been developed to demonstrate how correlations can result in absurd conclusions and do not identify the real causal affect.  For that reason, it would seem mandatory for EPA to have complete access to study data before giving the study sufficient credibility as a basis to adopt a major policy change.

The study in question did not originate in an agricultural setting, but rather in an urban housing setting where a particular organophosphate once held a legal use for control of household pests.  It should be noted that most of the organophosphates were never registered for household use.  It is clearly understood that conditions in a home limit the degrading process of pesticides as compared to agricultural environment conditions.  Sunlight, soil organisms, moisture, and many other factors of degradation are greatly reduced in home settings.  Similarly, movement in home settings greatly increases the likelihood of contacting treated areas.  The epidemiology study conducted by scientists at Columbia University reportedly focused on chlorpyrifos exposure in home settings and utilized a prenatal sample to document the exposure level.  The study reportedly followed the development of the children for the subsequent 7 years and conducted an IQ test.  The study reported a correlation in decreased IQ and exposure to chlorpyrifos as measured from the prenatal sample 7 years prior.  While this is admittedly a crude synopsis of a complex study, it does demonstrate why the study should be questioned openly before the Agency uses it to claim justification of a policy change.  In the Agency’s own assessment of the study, numerous flaws and limitations were highlighted that are critical to its interpretation to justify a 10X safety factor.  For example, no data was obtained after the prenatal sample to ensure additional exposure did not occur.  Were there other potential exposure concerns such as heavy metals (i.e. lead based paint) in the study homes? Were there subsequent uses of stored pesticides that resulted in exposure levels above those measured? Were demographic variables sufficiently controlled?  How do the study conclusions relate to the vast number of mandated EPA studies specifically designed to scientifically evaluate causal effects?  What evidence in the study scientifically shows the cause is a general mechanism of all organophosphates?  Additionally, the NCC does not find where the Agency compared the study to the vast number of required studies in order to weigh the contrast among conclusions. Such an approach would seem necessary given that the Agency has stated they can find no causal relationship between chlorpyrifos and these effects.
While the NCC is not refuting the Columbia University study, or other cited studies with suggested associations, the NCC believes the action of the Agency to implement a 10X safety factor on all organophosphates - most of which are used only in agricultural settings – represents a major policy change that warrants a separate public notice and comment period with a high level of transparency and scrutiny before being utilized to conduct multiple risk assessments.  However, the Agency has taken a different course by conducting multiple risk assessments with the 10X safety factor and announcing all simultaneously without separate consideration for the adoption of the 10X safety factor.  Of equal importance, these studies should be held to the same standards of transparency and scientific rigor required of registrants.

The NCC asks EPA to explain the causal mechanism involved in the results of the Columbia Study on chlorpyrifos and explain the data to demonstrate that mechanism in all organophosphates.  The NCC urges the Agency to withdraw all organophosphate risk assessments conducted with the 10X safety factor until such time that the Agency has completed notice, review with public comments, and final determination whether the 10X safety factor is supported by scientific evidence of a causal effect.
The NCC supports the protection of human health.  Unfortunately, the NCC has concerns that EPA is inferring harm beyond the scope of scientific data.  The NCC urges EPA to return to the historic path of reliance on credible scientific data and require all studies be evaluated based on scientific quality and merit.

The NCC urges EPA to retain all labeled uses of dimethoate for control of cotton pests.

Respectfully submitted,
Reece Langley
VP – Washington Operations
National Cotton Council