Dear EarthTalk: I've seen a lot of warm and fuzzy TV ads, some sponsored by BP Oil, urging me to vacation in the Gulf of Mexico. But are things really "back to normal?" -- Paul Shea, Dublin, Ohio
The Gulf of Mexico may be open for business and eager to attract tourists, but it's still unclear whether or not marine and coastal ecosystems there are healthy two years after BP's offshore drilling rig exploded 40 miles off the Louisiana coast, eventually releasing 205.8 million gallons of oil into the water column.
Five months after the April 2010 disaster, the Obama administration released a detailed recovery plan, calling for spending up to $21 billion -- most which would come from BP's civil penalties -- on clean-up and long-term ecosystem restoration. With much of this work -- designed to complement the restorative powers of Mother Nature -- well under way, some observers are pleased with the results so far.
"The natural recovery is far greater than what anybody hoped when it happened," said James Morris, a University of South Carolina biologist and a member of the National Research Council committee tasked by Congress to assess the effects of the spill on the Gulf's ecosystem. "The fears of most people -- that there would be a catastrophic collapse of the ecosystem in the Gulf -- never materialized."
"The fisheries have come back like gang busters," Morris reported. "One of the interesting findings was that after the oil spill, bait fish populations collapsed, and predator populations boomed. The reason was that there was no fishing pressure on the top predators because people stopped fishing after the spill. So the predator fish populations rebounded, and they grazed down their prey."
Not everyone shares such a rosy view. The international environmental group Greenpeace reported: "Throughout the food chain, warning signs are accumulating. Dolphins are sick and dying. Important forage fish are plagued with gill and developmental damage. Deepwater species like snapper have been stricken with lesions and their reefs are losing biodiversity. Coastal communities are struggling with changes to the fisheries they rely upon. Hard-hit oyster reefs aren't coming back and sport fish like speckled trout have disappeared from some of their traditional haunts."
Still other observers argue that two years is not enough time to tell whether the region's ecosystems will be severely damaged long term.
"We really don't know the effects the Deepwater Horizon spill had in the deep sea because we know little about the ecosystem processes there," reported Gary Cherr, director of UC Davis' Bodega Marine Laboratory and a lead author on a recently released paper published in the journal Bioscience. Cherr and his fellow researchers, including leading oceanographers, ecotoxicologists and ecologists, conclude that scientists need more time to study how to contain damage from such accidents, especially given the trend to seek new sources of oil in off-shore regions around the U.S. and beyond.
"The deep sea is not a dead zone. It's not a desert. There's a lot of life down there," added Cherr. "Unfortunately it's not until a disaster happens that we try to piece together the impacts. That's difficult to do when you don't have a complete -- or even partial -- understanding of the ecosystem."
Dear EarthTalk: Lead was long ago phased out of automobile gasoline, but it is still in aviation fuel and is now the largest source of lead emissions in the U.S. What's being done? -- L. Eber, Rye, N.Y.
Yes, aviation fuel emerged as the largest source of lead emissions in the U.S. once lead was phased out of automotive gasoline beginning in the 1970s. While jets, which comprise the majority of commercial aircraft, don't use leaded fuel, smaller, piston-engine planes use enough leaded aviation fuel (nicknamed "avgas") to account for half of the lead pollution in American skies, making it a real air quality issue.
Some of the health effects of repeated exposure to lead include damage to the central nervous system, kidneys and red blood cells, and decreased function in the cardiovascular and immune systems. Lower IQ levels and learning disabilities can also result from lead exposure, especially in children, whose young bodies are more sensitive than those of adults. And scientists at the National Toxicology Program have concluded that lead and lead compounds are "reasonably anticipated to be human carcinogens."
The U.S. Environmental Protection Agency recognizes lead as a neurotoxin and in 2008 set tough new standards for how much of it is safe in our air. In 2010 the agency identified 16 U.S. regions that fail to meet clean air standards for airborne lead; all either contained or were near airports where leaded avgas is the norm. But the EPA has not yet restricted lead in avgas, even though unleaded avgas is available.
A 2011 Duke University study found that kids living within 500 meters of an airport where leaded avgas is used have higher blood lead levels than other children, with elevated lead levels in blood found in kids as far as one kilometer away. The EPA estimates that 16 million Americans live close to one of 22,000 airports where leaded avgas is routinely used -- and 3 million children go to schools near these airports.
Friends of the Earth, a leading green group, filed suit against the EPA in late 2011, demanding that it respond to a petition originally submitted in 2006 asking for regulation of lead emissions from general aviation aircraft under the Clean Air Act. That original petition requested that the EPA issue a finding that emissions from aircraft using leaded avgas endanger public health.
"EPA has repeatedly concluded that lead is extremely toxic to humans, wildlife and the environment and causes health effects even at low doses," Marcie Keever, FoE's legal director, said. "EPA's continuing failure to do what the law requires and address this pollution leaves us no choice but to take this critical public health issue to the courts."
According to FoE, 70 percent of small planes could already be using unleaded avgas with no retrofitting needed. The group says that a meaningful plan by the EPA to ban leaded avgas could spark investment in technologies to replace the engines in the rest of the small plane market that relies on leaded avgas.
Some members of the aviation community are taking matters into their own hands. The Aviation Fuel Club, which aims to make aviation fuel affordable for sport aviators, is working to ensure that unleaded avgas is available at many airports across the country. Green groups are pleased with this development, but want the U.S. government to institute binding restrictions on the use of lead in aviation fuel.
EarthTalk is by Roddy Scheer and Doug Moss of E -- The Environmental Magazine (www.emagazine.com). Send questions to: email@example.com.