[Marxism] Additional arguments against Gulf of Mexico optimism

Louis Proyect lnp3 at panix.com
Fri Jul 30 07:49:24 MDT 2010


http://www.huffingtonpost.com/2010/07/29/scientists-find-evidence_n_664298.html
Scientists Find Evidence That Oil And Dispersant Mix Is Making Its 
Way Into The Foodchain

by Dan Froomkin

Scientists have found signs of an oil-and-dispersant mix under the 
shells of tiny blue crab larvae in the Gulf of Mexico, the first 
clear indication that the unprecedented use of dispersants in the 
BP oil spill has broken up the oil into toxic droplets so tiny 
that they can easily enter the foodchain.

Marine biologists started finding orange blobs under the 
translucent shells of crab larvae in May, and have continued to 
find them "in almost all" of the larvae they collect, all the way 
from Grand Isle, Louisiana, to Pensacola, Fla. -- more than 300 
miles of coastline -- said Harriet Perry, a biologist with the 
University of Southern Mississippi's Gulf Coast Research Laboratory.

And now, a team of researchers from Tulane University using 
infrared spectrometry to determine the chemical makeup of the 
blobs has detected the signature for Corexit, the dispersant BP 
used so widely in the Deepwater Horizon

"It does appear that there is a Corexit sort of fingerprint in the 
blob samples that we ran," Erin Gray, a Tulane biologist, told the 
Huffington Post Thursday. Two independent tests are being run to 
confirm those findings, "so don't say that we're 100 percent sure 
yet," Gray said.

"The chemistry test is still not completely conclusive," said 
Tulane biology professor Caz Taylor, the team's leader. "But that 
seems the most likely thing."

With BP's well possibly capped for good, and the surface slick 
shrinking, some observers of the Gulf disaster are starting to let 
down their guard, with some journalists even asking: Where is the oil?

But the answer is clear: In part due to the1.8 million gallons of 
dispersant that BP used, a lot of the estimated 200 million or 
more gallons of oil that spewed out of the blown well remains 
under the surface of the Gulf in plumes of tiny toxic droplets. 
And it's short- and long-term effects could be profound.

BP sprayed dispersant onto the surface of the slick and into the 
jet of oil and gas as it erupted out of the wellhead a mile 
beneath the surface. As a result, less oil reached the surface and 
the Gulf's fragile coastline. But more remained under the surface.

Fish, shrimp and crab larvae, which float around in the open seas, 
are considered the most likely to die on account of exposure to 
the subsea oil plumes. There are fears, for instance, that an 
entire year's worth of bluefin tuna larvae may have perished.

But this latest discovery suggests that it's not just larvae at 
risk from the subsurface droplets. It's also the animals that feed 
on them.

"There are so many animals that eat those little larvae," said 
Robert J. Diaz, a marine scientist at the College of William and Mary.

Oil itself is of course toxic, especially over long exposure. But 
some scientists worry that the mixture of oil with dispersants 
will actually prove more toxic, in part because of the still not 
entirely understood ingredients of Corexit, and in part because of 
the reduction in droplet size.

"Corexit is in the water column, just as we thought, and it is 
entering the bodies of animals. And it's probably having a lethal 
impact there," said Susan Shaw, director of the Marine 
Environmental Research Institute. The dispersant, she said, is 
like " a delivery system" for the oil.

Although a large group of marine scientists meeting in late May 
reached a consensus that the application of dispersants was a 
legitimate element of the spill response, another group, organized 
by Shaw, more recently concluded "that Corexit dispersants, in 
combination with crude oil, pose grave health risks to marine life 
and human health and threaten to deplete critical niches in the 
Gulf food web that may never recover."

One particular concern: "The properties that facilitate the 
movement of dispersants through oil also make it easier for them 
to move through cell walls, skin barriers, and membranes that 
protect vital organs, underlying layers of skin, the surfaces of 
eyes, mouths, and other structures."

Perry told the Huffington Post that the small size of the droplets 
was clearly a factor in how the oil made its way under the crab 
larvae shells. Perry said the oil droplets in the water "are just 
the right size that probably in the process of swimming or 
respiring, they're brought into that cavity."

That would not happen if the droplets were larger, she said.

The oil droplet washes off when the larvae molt, she said -- but 
that's assuming they live that long. Larvae are a major food 
source for fish and other blue crabs -- "their siblings are their 
favorite meal," Perry explained. Fish are generally able to 
excrete ingested oil, but inverterbrates such as crabs don't have 
that ability.

Perry said the discovery of the oil and dispersant blobs is very 
troubling -- but not, she made clear, because it has any impact on 
the safety of seafood in the short run. "Unlike heavy metals that 
biomagnify as they go up the foodchain, oil doesn't seem to do 
that," she said. Rather, she said, "we're looking at long-term 
ecological effects of having this oil in contact with marine 
organisms."

Diaz, the marine scientist from William and Mary, spoke at a 
lunchtime briefing about dispersants on Capitol Hill on Thursday.

Dispersant, he explained, "doesn't make the oil go away, it just 
puts it from one part of the ecosystem into another."

In this case, he said, "the decision was to keep as much of the 
oil subsurface as possible." As a result, the immediate impact on 
coastal wildlife was mitigated. But the effects on ocean life, he 
said, are less clear -- in part because there's less known about 
ocean ecosystems than coastal ones.

"As we go further offshore, as the oil industry has gone offshore, 
we find that we know less," he said. "We haven't really been using 
oceanic species to assess the risks, and this is a key issue."

(Similar concerns have been expressed about the lack of important 
data that would allow scientists to accurately assess the effects 
of the spill on the Gulf's sea turtles, whose plight is emerging 
as particularly poignant.)

Diaz warned of the danger posed to bluefin tuna -- and also to 
"the signature resident species in the Gulf, the shrimp." He noted 
that all three species of Gulf shrimp spawn offshore before moving 
back into shallow estuaries.

Diaz also expressed concern that dispersed oil droplets could end 
up doing great damage to the Gulf's many undersea coral reefs. "If 
the droplets agglomerate with sediment," he said, "they could even 
settle to the bottom."

Nancy Kinner, co-director of the Coastal Response Center at the 
University of New Hampshire, said the use of dispersants in this 
spill raises many issues that scientists need to explore, starting 
with the effects of long-term exposure. She also noted that 
scientists have never studied the effects of dispersants when 
they're injected directly into the turbulence of the plume, as 
they were here, or at such depth, or at such low temperatures, or 
under such pressure.

She also said it will be essential for the federal government to 
accurately determine how much oil made it out of the blown well. A 
key data point for scientists is the ratio of dispersant to oil, 
she said, and "if you don't know the flow rate of the oil, you 
don't know what you dispersant to oil ratio is."

After a series of ludicrous estimates, the federal government 
settled last month on an official estimate of about 20,000 to 
40,000 barrels a day, but BP is widely expected to contest that 
figure and some scientists think it is still a low-ball estimate.

There seems to be no doubt that history will record that the use 
of dispersants was good for BP, making it harder to tell how much 
oil was spilled, and reducing the short-term visible impact. But 
what's less clear is whether it will turn out to have been good 
for the Gulf.




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