Remember the Deepwater Horizon drilling disaster? It’s been a few years now. This video is a brief update on some of our research on how the spill might have affected, and may still be affecting oysters off the coasts of Louisiana, Alabama and Florida. This has been very slow and difficult work, mostly because we have been monitoring the oysters for several years, and have had to develop protocols for the tissue analyses. But it is now moving toward publication.
On April 18th, as the second anniversary of the Deepwater Horizon accident approached, the California Academy of Sciences published a press release regarding some of our research on coastal oysters in the Gulf of Mexico. You will find a nice reprint of it here in Science Daily. In a nutshell, our study compared specimens collected in the Gulf during the 20th century, in May 2010 prior to landfall of the spill, and August 2010 (and some intervals after that) after landfall of the spill. We also included a specimen collected off North Carolina in 2010. Our main conclusions are:
- Concentrations of several heavy metals, vanadium, cobalt and chromium, are significantly higher in shells exposed to the spill.
- Concentrations of several heavy metals, vanadium, cobalt and lead, are significantly higher in gill and muscle tissues of specimens exposed to the spill.
- Eighty seven percent of specimens exposed to the spill and examined by us show transformation (metaplasia) of gill tissues.
It is very important to note that these results are preliminary, and both our sample sizes and coverage (temporal and geographic) will be increased as time goes on. It is also important to note that we are not claiming that the levels of these metals are dangerous to humans. Much more work, and additional expertise, are required to make that decision. We are ultimately interested in the environmental impact of the spill, and the ability to assess and trace the impacts of future such accidents.
Nevertheless, our results have proven to be quite unpopular with some folks, and has drawn both ire and support from various quarters. A very nice summary of the controversy, and the exchanges, can be found in this article from Food Safety News. To the supporters, you have my sincere appreciation.
While some people may see oysters as only a delicious delicacy, researchers are using them to understand the long term environmental impact of the Gulf oil spill. Oyster shells turn out to hold important clues about past ecological disasters. This hour, the importance of oysters – more than just good eating, these mollusks play a key role in the ecosystem. Guests PETER ROOPNARINE, a curator at the California Academy of Natural Science and PAUL CALLOMON, a collections manager at the Academy of Natural Science, tell us about reading oyster shells and the threats oysters face from pollution, climate change, acidification, overharvesting, and invasive species.
(The Oakland Tribune and The Contra Costa Times)