August 4, 2014

Veronica Dutch 

Office of Pesticide Programs (OPP)

Environmental Protection Agency (EPA)

Docket Center (EPA/DC) (28221T)

1200 Pennsylvania Ave., N.W.

Washington DC 20460–0001

Subject: Registration Review Proposed Interim Decision – Metofluthrin 

(Docket # EPA–HQ–OPP–2012–0105)

Dear Ms. Dutch:

On behalf of the California Stormwater Quality Association (CASQA1), thank you for the 

opportunity to comment regarding the EPA’s proposed decision to terminate the Registration 

Review of metofluthrin. We are very concerned about the potential consequences of this 

decision. Terminating metofluthrin's review:

• opens the door to increases in use without measures to prevent water pollution, and 

• prevents your office from requiring metofluthrin products to implement the mitigation 

measures that will be required for other pyrethroids.

On August 23, 2013, CASQA registered our concerns regarding the metofluthrin review work 

plan. EPA had neither proposed to examine water quality risks nor to review metofluthrin in 

parallel with the risk assessments of other pyrethroids. We are confounded that, rather than 

responding to our concerns, EPA has determined there is insufficient reason to continue the 

review altogether.

Pesticide water pollution has created a persistent regulatory burden for many of our municipal

members. Currently, EPA has listed 622 California water bodies as impaired by pesticides under 

Section 303(d) of the Clean Water Act; of those, 16 are listed for pyrethroids.2 Further, in 2013, 

CASQA compiled a report of statewide monitoring data for pyrethroids, concluding that 

pyrethroids are present in urban waterways throughout California at concentrations above the 

EPA chronic Aquatic Life Benchmarks for aquatic invertebrates in water.3 

 

1 CASQA is comprised of stormwater quality management organizations and individuals, including cities, counties, 

special districts, industries, and consulting firms throughout California. Our membership provides stormwater 

quality management services to more than 22 million people in California. 2 State Water Resources Control Board’s 2010 303(d) list is available at 

http://www.waterboards.ca.gov/water_issues/programs/tmdl/integrated2010.shtml. 3 Ruby, Armand. 2013. Review of Pyrethroid, Fipronil and Toxicity Monitoring from California Urban Watersheds. 

Available at https://www.casqa.org/LinkClick.aspx?fileticket=t%2btwBGMxunc%3d&tabid=194&mid=995.
CASQA Comments on Metofluthrin Proposed Interim Decision August 4, 2014

Docket # EPA–HQ–OPP–2012–0105

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As regulatory actions to protect water quality, including TMDLs, are taken to address those 

pyrethroids, manufacturers will seek to replace those with other, less-regulated insecticides. If 

EPA continues on this path to terminate review of metofluthrin, this will pave the way for 

metofluthrin use to increase as a replacement for other, more heavily regulated pyrethroids. As 

use increases, so does the likelihood of aquatic toxicity.

Therefore, it remains important for EPA to continue with its previous promise to address 

pyrethroid-caused water pollution through Registration Review of all pyrethroids as a group. 

EPA has recognized the importance of this methodology, noting in past Decisions (e.g., 

cypermethrin4) there is a relationship between pyrethroids and their uses, in that if a specific use 

were to be restricted for one pyrethroid, another would likely replace that pyrethroid. 

As you know, there remains no practical and cost-effective treatment technology that 

municipalities can use to remove these pesticides from stormwater runoff. The only technically 

and economically feasible way for municipalities to comply with current and future Clean Water 

Act requirements is for EPA to effect a true source control approach by using its regulatory 

authorities to prohibit pesticide uses that inevitably create pesticide related toxicity in urban 

waterways.

For these reasons, and per the details presented in our August 2013 comment letter, we 

respectfully ask you to reconsider your determination. 

Thank you for your consideration of our comments. If you have any questions, please contact

Dave Tamayo, CASQA Pesticides Subcommittee Co-Chair, at (916) 874-8024 

(tamayod@SacCounty.net); or CASQA Executive Director Geoff Brosseau at (650) 365-8620.

Sincerely,

Gerhardt Hubner, Chair

California Stormwater Quality Association

cc: Richard Keigwin, Jr., Director, EPA OPP Pesticide Re-Evaluation Division

Donald Brady, Director, EPA OPP Environmental Fate and Effects Division

Linda Arrington, EPA OPP Pesticide Re-Evaluation Division

Marquea King, EPA OPP Pesticide Re-Evaluation Division

Kevin Costello, EPA OPP Pesticide Re-Evaluation Division

Tracy Perry, EPA OPP Pesticide Re-Evaluation Division

Monica Wait, EPA OPP Pesticide Re-Evaluation Division

Molly Clayton, EPA OPP Pesticide Re-Evaluation Division

Mah Shamim, EPA OPP, Environmental Fate and Effects Division

 

4 EPA (2006). Reregistration Eligibility Decision for Cypermethrin. EPA OPP-2005-0293. Page 51.
CASQA Comments on Metofluthrin Proposed Interim Decision August 4, 2014

Docket # EPA–HQ–OPP–2012–0105

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Rosanna Louie-Juzwiak, EPA OPP, Environmental Fate and Effects Division

Hannah Yingling, EPA OPP, Environmental Fate and Effects Division

James Wolf, EPA OPP, Environmental Fate and Effects Division

Dana Spatz, EPA OPP, Environmental Fate and Effects Division

Melissa Panger, EPA OPP, Environmental Fate and Effects Division

Betsy Southerland, Director, EPA Office of Water, Office of Science and Technology

Andrew Sawyers, Director, EPA Office of Water, Office of Wastewater Management

Nan Singhasemanon, California Department of Pesticide Regulation

Jane Diamond, Director, Water Division, EPA Region 9

Patti TenBrook, EPA Region 9 

Debra Denton, EPA Region 9

Eugene Bromley, EPA Region 9

Erin Foresman, EPA Region 9

Richard Breuer, California State Water Resources Control Board

Tom Mumley, California Regional Water Quality Control Board, San Francisco Bay Region

Janet O'Hara, California Regional Water Quality Control Board, San Francisco Bay Region

Daniel McClure, California Regional Water Quality Control Board, Central Valley Region

Tessa Fojut, California Regional Water Quality Control Board, Central Valley Region

Jowin Cheung, California State Water Resources Control Board 

Charles Cheng, California Regional Water Quality Control Board, San Diego Region 

Mary Fiore-Wagner, California Regional Water Quality Control Board, Lahontan Region 

Johnny Gonzales, California State Water Resources Control Board 

Paul Hann, California State Water Resources Control Board 

Peter Meertens, California Regional Water Quality Control Board, Central Coast Region 

Jenny Newman, California Regional Water Quality Control Board, Los Angeles Region 

Amanda Palumbo, California State Water Resources Control Board 

Jodi Pontureri, California State Water Resources Control Board 

Terri Reeder, California Regional Water Quality Control Board, Santa Ana Region 

James Smith, California Regional Water Quality Control Board, San Diego Region 

Doug Wylie, California Regional Water Quality Control Board, Colorado River Region 

Ben Zabinsky, California Regional Water Quality Control Board, North Coast Region 

Man Voong, California Regional Water Quality Control Board, Los Angeles Region

Kelly D. Moran, Urban Pesticide Pollution Prevention Partnership

CASQA Board of Directors, Executive Program Committee and CASQA Pesticides 

Subcommittee