I have been mulling over the best way to respond to Bob Pyle's guest column for a couple of weeks. OK. I admit that I don't always come up with the perfect most accurate and concise way to convey information to reporters. Still I think Bob Pyle was unfair to me. More than anyone in Pacific County, I have worked to see that residents have access to accurate information about spartina control herbicides straight from the scientific experts. Working for the local non-profit Coastal Resources Alliance, I organized numerous public forums to address the concerns of local residents. One forum I organized was specifically devoted to explaining the research that has been done to evaluate the risks of imazapyr before it was registered for aquatic use. Toxicologists from the University of Washington and Washington State University were among the speakers.
But this is not about me and what I have done to try to provide people with the facts. The real message of Bob Pyle's column was about whether people should trust government or science when it comes to decisions about herbicides. Mr. Pyle seems to suggest we should not. Maybe it would build his confidence if he knew how hard it is to register a new herbicide for aquatic use. Before imazapyr was registered for aquatic use in 2004, EPA had not registered a new aquatic herbicide since 1986. The EPA team that was assembled to decide on imazapyr was made up of 15 scientists. Their official decision document included a 28-page bibliography listing hundreds of sources of scientific information. The Registration Eligibility Decision (RED) is available at EPA's Web site - www.epa.gov/oppsrrd1/reregistration/imazapyr/ - along with numerous other documents considered during the registration process. If that isn't sufficient, there's more. Washington state also conducted a review for its Environmental Impact Statement. The state permit review was specific to the use of imazapyr in Washington's estuaries to control spartina. The expert risk evaluation used in the State EIS is available online at www.ecy.wa.gov/programs/wq/pesticides/final_pesticide_permits/noxious/risk_assessment_Imazapyr.pdf. That document includes six pages of bibliographic references.
The impacts of imazapyr on phytoplankton have been studied. They were addressed in the state and federal reviews. The state review addressed the risks to algae in the following way: Risks to algae, based on hazard quotient calculations, are insignificant-within the same order of magnitude as risks characterized for aquatic invertebrates (Table 5-3). (p.80)
What was most disappointing was his reference to Agent Orange. I hope no one misread what he wrote. Bob did not claim that imazapyr is as dangerous as Agent Orange. He did not claim that imazapyr contains dangerous contaminants. He only pointed out that a couple herbicides used in the past had dangerous contaminants. I'm old enough to remember Agent Orange's use as a jungle defoliant in the Vietnam War. The impacts of the contaminant in Agent Orange were not at all subtle. So why did Bob bring up Agent Orange? It made me wonder, is he intentionally trying to scare people? Is he seriously suggesting that the science of pesticide risk evaluations is so cursory and unreliable that dangerous contaminants like Agent Orange could slip through without anyone noticing? I hope not.
I am glad that Bob acknowledged the scientific consensus that invasive plants are one of the greatest threats to native habitat we face. We are making excellent progress in ridding the bay of invasive spartina. There are a lot of people working very hard to restore the Bay to its pre-invasion condition. I guess it is human nature that some people would rather lecture from the sidelines about the world they would prefer - a world in which we use no chemicals and cost is no object. Mechanical control of nearly 20,000 acres of spartina - most of which were in soft and hard-to-reach mudflats - was never feasible. Even if it had been feasible, the impacts of repeated mechanical operations-of Rototilling the substrate over and over again - would have been significant and probably far greater than the impacts of the modern herbicides we are using.
The good news is that imazapyr is working well. Water quality is being tested regularly. Dr. Kim Patten's research has documented that the migratory birds are coming back. They are feeding in the mudflats that were covered with spartina just a few years ago. We are winning back the bay.