Climatide

Oysters are known to sequester high levels of toxic metals (e.g. lead, cadmium, and zinc) from contaminated sediments. Less is known about long-term accumulation of organic contaminants (e.g pharmaceuticals, personal care products, and pesticides), but NOAA’s MusselWatch program and the Massachusetts Water Resources Authority (MWRA) have done long term studies of resident and caged mussels in Massachusetts. A very nice review of these long datasets was just published (Marine Environmental Research Volume 70, Issue 5, December 2010, Pages 343-357).
[MusselWatch was a national NOAA bivalve monitoring program using mussels, oysters, and clams that was terminated for lack of funding].

It is likely that there is both bioconcentration and metabolism of organic contaminants by bivalves, but what this means for the consumer isn’t clear.

It saddens me that this type of “journalism” is being posted on NPR’s website, even under the disguise as a blog. It is neither journalism nor even an editorial but a summary of an article selectively paraphrased and even retitled to add shock value or perhaps to meet the author’s agenda. It concerns me that the public will quickly read the new title and take it as fact, which I suppose is the author’s intention. I would expect this type of spin on Fox News but not on NPR.

The truth is that this not a problem. In fact the Town of Falmouth already performs aquaculture in the salt ponds however very inefficiently and not under the title of aquaculture. Every year the town buys seed quahogs, oysters, and scallops from hatcheries elsewhere in the state, raises them in nurseries, then “plants” them in the salt ponds for commercial “wild harvesters” and general public to harvest up. This common practice is usually thought of as “resource enhancement” but it basically is aquaculture done very inefficiently. The impacts of seeding and harvesting is never questioned because it has been done for many years, not realized as “aquaculture”, and is not a problem.

People eat shellfish out of these salt ponds every single day. No one is getting sick from eating these aquaculture shellfish planted by the town unless the product is mishandled after harvesting (just as any food product would). Shellfish feed at the very base of the food chain, so how bioconcentration is considered a problem here and not in fish caught in the ponds is strange. If one reads into any of the recent scientific literature of shellfish and toxic metals they will find that results in fact do no support the previous post’s statements. Shellfish feed on plankton, which feed on the nutrients coming from the ground water. This is similar to a cow feeding on grass that was fertilized with compost. It doesn’t mean you are eating the compost, you are eating the nutrients that that have been transferred to the cow via the grass.

I should have disclosed in my previous post that I am a oyster grower in Falmouth, so have a strong interest in seeing that unfounded and incorrect statements relating to my business are not propagated. Perhaps the author of the previous post (Jed) also has something to disclose?

I am genuinely sorry to offend. It was never my intention to portray this as anything other than a nod to another’s reporting; Elise Hugus is a journalist I respect and trust. And your point about nitrogen not posing a risk to consumers is dead on. I am actually quite a fan of oyster aquaculture as a means for improving water quality and restoring ecosystem function.
My agenda (as you put it) is to raise public awareness of a problem that is gaining more and more recognition – that of pharmaceuticals and hormone-like chemicals in wastewater (and, thus, the coastal waters into which wastewater flows). As a concerned citizen, former toxicologist, and journalist, I take issue with the argument that we’ve never worried about this before so shouldn’t worry about it now. If you have data to show that oysters are not absorbing and accumulating pharmaceuticals and hormone mimics, I would be only too happy to share that information with the public.

How does one prove a negative? The burden is on you as a scientist and a responsible journalist to prove that oysters floating on the surface in these waters, feeding for 6-7 months a year (they are dormant in cold water), and harvested after 1-2 seasons do have this issues you insinuate. This kind of prove a negative logic would result in never ending and never resolved questions. My argument isn’t that “we’ve never worried about this before so shouldn’t worry about it now”. It is against yelling fire without knowing if there really is a fire. These kind of postings might not seem like a big deal, but they can have implications on many people’s livelihoods. Blogs about another blog usually aren’t something that I would take the time to be concerned with, except when it it is posted under a respectable media news source that a large audience trusts.

These are not contaminated sediments. Referring to shellfish from places like Boston Harbor or New York Harbor is not the same as comparing them from an area of no contamination. Shellfish from clean waters are clean. There is literature proving that and even more current and locally specific coming out that continues to prove that. It makes sense to use shellfish as a senitial spices but to say these have contamination so all have contamination doesn’t make sense. It is a bit like saying a pet canary here on the Cape is going to die of black lung because the ones in a Chinese coal mine are dyeing of black lung.

Your last sentence seems very silly and unscientific. I question the motivation for Jed’s post and relationship to the referred to blog about a blog.

Posting personal blogs on news media web sites seems like a very slippery slope……especially when the blogs uses other blogs as a reference. It is often hard to discern if the blog posted on a news distribution media source is an news article based on fact or just a blog.

In refer to your sentence: “My agenda (as you put it) is to raise public awareness of a problem that is gaining more and more recognition – ”

So using this logic: the next time I go into a movie theater I have the right to start yelling “there is going to be a fire!” because there is flammable material in the building. When they go to kick me out I can argue: “Hey, you can’t prove that there wasn’t going to be a fire”.

NPR should be responsible and remove this post from its website.

You have a point … one that I will attempt to address in the near future.

While there is great concern over hormone disruptors and the other chemicals that go into septics, how far they migrate is unknown. What is known is that they don’t appear to be causing fish and shellfish contamination as you insinuate. The projected $400M expenditure, $40,000 per household for the Town of Falmouth, would have a substantial impact if a significant portion were spent on direct environmental remediation of the degraded areas we are trying to restore with this indirect approach of sewers. We need to look more closely at how to maximize natures decentralized scrubbers and point source reduction. Sewers only transfer the problem at great capital and energy cost and they don’t by themselves recover lost critical habitat.