http://www.timesonline.co.uk/tol/news/environment/article7134581.ece
May 24, 2010
Oil spill brings ‘death in the ocean from top to bottom’
Frank Pope
It has been an hour since our sport-fishing boat started streaking through the freshly oil-soaked marshes of Pass a Loutre, but we’re still only halfway through the slick. Eighteen miles out and the stink of oil is everywhere. Rashes of red-brown sludge are smeared across vast swaths, between them a swell rendered faintly psychedelic with rainbow-coloured swirls.
Cutting the engines, we slide to a stop near Rig 313. We’re not supposed to be in the restricted zone, but other than the dispersant-spraying aircraft passing overhead there’s no one to see us. Despite the thick oil, we’ve seen only two clean-up boats out of the 1,150 that the response claims to have on site: one was broken down, the other was towing it.
Skimming and burning are the most visible elements of the clean-up operation, and that’s no accident. Over the past few days it’s become clear that far more oil is gushing from the seabed than BP had admitted. Oil has been prevented from reaching the surface by dispersants injected into the flow some 5,000ft below, but is spreading through the midwater in vast, dilute plumes.
Along with the marine toxicologist Susan Shaw, of the Marine Environmental Research Institute, I’ve come to peer into the hidden side of the Deepwater Horizon disaster. Wreathed in neoprene and with Vaseline coating the exposed skin around our faces, we slip into the clear water in the lee of the boat. Beneath the mats of radioactive-looking, excrement-coloured sludge are smaller gobs of congealed oil. Taking a cautious, shallow breath through my snorkel I head downwards. Twelve metres under, the specks of sludge are smaller, but they are still everywhere.
Among the specks are those of a different hue. These are wisps of drifting plankton, the eggs and larvae of fish and the microscopic plants and animals that form the base of almost all marine food webs. Any plankton-eating fish would now have trouble distinguishing food from poison, let alone the larger filter-feeders.
Onshore, small landfalls of the same sludge have started to cause panic among locals as they coat the marshes. Here, just a few feet beneath the surface, a much bigger disaster is unfolding in slow motion.
“This is terrible, just terrible,” says Dr Shaw, back on the boat. “The situation in the water column is horrible all the way down. Combined with the dispersants, the toxic effects of the oil will be far worse for sea life. It’s death in the ocean from the top to the bottom.”
Dispersants can contain particular evils. Corexit 9527 – used extensively by BP despite it being toxic enough to be banned in British waters – contains 2-butoxyethanol, a compound that ruptures red blood cells in whatever eats it. Its replacement, COREXIT 9500, contains petroleum solvents and other components that can damage membranes, and cause chemical pneumonia if aspirated into the lungs following ingestion.
But what worries Dr Shaw most is the long-term potential for toxic chemicals to build up in the food chain. “There are hundreds of organic compounds in oil, including toxic solvents and PAHs (polycyclic aromatic hydrocarbons), that can cause cancer in animals and people. In this respect light, sweet crude is more toxic than the heavy stuff. It’s not only the acute effects, the loss of whole niches in the food web, it’s also the problems we will see with future generations, especially in top predators.”
When a gap in the slick opens, I dive on one of the huge steel legs of the rig. Swirling around it are dozens of some of the biggest fish I’ve seen in nearly 20 years of diving. Huge cobia, amberjack, mangrove snapper and barracuda thrive on the shelter provided by the rig structures, creating some of the most sought-after game fishing in the United States: our skipper claimed that he’d hosted three world record-breaking catches last year.
“They’ll be healthy enough now, but it’s just a matter of time,” Dr Henry Bart, a fish biologist at Louisiana’s Tulane University, told me later. “Cobia feed on upper water-column species. The oil is going to magnify up through the food chain.”
What happens to marine species in the dark, unseen waters below us is less certain. In the Gulf the depths are better known than almost anywhere in the world, for the oil industry has to show what exists on the seabed before any drilling can begin. This, along with an on-going Census of Marine Life, has helped to reveal that life within seabed sediments is astoundingly varied.
A pod of sperm whales resides off New Orleans and is believed to be dining on giant squid. These ultimately depend on the tiny specks of life that are slowly being poisoned at the surface.
What happens next, no one can say for sure.
Special thanks to Richard Charter