02/03/2011: "Are Our Waters Are Toxic To Salmon?"
Tried by a Hangman’s Jury| Homeowners
According to recent figures, 138 people have been released from death row because of DNA evidence, and an almost equal number have been released from prison. Each of these cases represents an instance where a jury relied on eyewitness accounts and probably some form of semi-quantitative evidence. But without definitive science, they were wrong.
Environmental science can be a lot like detective work. We look for the agents of environmental impacts. To assist in finding the right agent, there has arisen a very useful infrastructure of methods, procedures, and rules from EPA, the state, and from third-party organizations like the American Society for Testing and Materials (ASTM).
Kwiaht turns out a prolific volume of interesting work products. Nevertheless, these work products do not follow standard methods for producing scientifically defensible data. In fact, they frequently fail to come even close, but that is not a criticism. They do the best they can. It would be impossible to turn out defensible reports given their limited resources. Overall, I support citizen-based efforts like theirs.
But I question the motives of people like Mr. Olson [see letter below] who try to use questionable data to advance their own limited views. Mr. Olson inflates the certainty of Kwiaht data and conflates the effects of different surfactants. Generally, if you do not know the difference between an ELISA and an HRGC/HRMS, or if you do not understand the need for organic carbon normalization for non-ionic compounds in sediment, or if you think that parts-per-billion is the same as micrograms-per-liter of seawater; then you have no business drawing risk-based conclusions from environmental studies.
Mistaking eyewitness accounts, qualitative, or semi-quantitative information for definitive science is the biggest mistake of all. That is the problem that is all around us.
In 2008 Lopez based non-profit Kwiaht, conducted a well-crafted survey to discover if household-use pesticides or surfactants have accumulated in surface water or sediments in measurable amounts, and whether they may already pose a threat to salmon and other aquatic organisms in SJC.
The Common Sense Alliance also performed a survey for pesticides, herbicides, metals and phthalates in soils and surface water in SJC. Their study sampled only four sites and may have used less sensitive tests. Many chemicals are toxic at parts per billion (ppb), some even in the parts per trillion range. Their study found all results to be well within the “background” range for all compounds, except zinc.
Kwiaht sampled thirty-two sites throughout the county and found that 69% of the sites tested positive for pyrethroid pesticides at levels of 1-2 ppb. Pyrethroids have low mammalian toxicity, but are extremely toxic to fish and organisms that form the base of the nearshore food chain. Levels of less than 2 ppb are toxic to salmon; therefore, it can be stated, with confidence, that pesticides at levels that threaten salmon are already widespread in our waters.
Surfactants are widely used as emulsifiers. They were detected in all 32 sites at an average level of 570 ppb, which just exceeds EPA drinking water standards. Nonylphenol, a breakdown product of surfactants, is toxic to humans and aquatic wildlife, including salmon. The main SJC sources for both surfactants and pyrethroids are outdoor use and runoff.
The Kwiaht study convincingly demonstrates that we have a chemical surface runoff problem that can kill salmon, affect their ability to avoid predation, even at very low chemical levels, and threaten their nearshore food sources.
CSA has asked: Where is the problem? The answer: It’s here, all around us.