A Toxic Brew in the Gulf of Mexico
Molly Rauch, MPH
May 6, 2010
Last month an oil rig in the Gulf of Mexico exploded, killing 11 people. The destroyed oil rig is releasing more than 200,000 gallons of oil into the Gulf each day. This disaster threatens to dwarf the notorious Exxon Valdez spill, which dumped 11 million gallons of crude oil into the remote Prince William Sound in 1989. By contrast, the current catastrophe has already leaked over 12 million gallons, according to one environmental group. And the gallons keep pouring out, despite automated robot repair efforts.
Until the leak is plugged, and for many weeks thereafter, there are several instruments of defense against the oil. One is the thousands of feet of boom being laid out across the Gulf coast to prevent the oil from reaching wildlife and people. Another is the widespread application of chemical dispersant to the spill.
Concerns about the oil spill have been focused on the effects on wildlife and its delicate habitat, which are potentially grave. Alarm bells are ringing as well about the long-term effects on the Gulf Coast economy, especially its large and productive fishery. The National Marine Fisheries Service estimated the annual commercial seafood harvest from the five U.S. Gulf states at $661 million. Already fishing has been banned through much of the Gulf due to fears of oil contamination.
But there are other issues about which we here at PSR are also concerned. These relate to the public health consequences of the oil spill.
The oil itself is highly toxic. According to a 2009 report from Oceana, the threat to wildlife goes far beyond the oiling of feathers. Compounds in oil threaten the reproductive health of wildlife, cause tissue and organ damage, cause deformities and genetic mutations in the larvae of fish, increase the risk of developmental defects and mortality in turtles, lead to immune system impairment and suppression, impair maintenance of blood pressure in birds, trigger anemia in birds, and cause cancer in animals who ingest the oil, among other health effects.
On the Gulf Coast, all this wildlife lives in close proximity to people. And there is much in the oil for people to worry about as well. According to Gina Solomon, MD, Senior Scientist at the Natural Resources Defense Council:
Oil contains a mixture of chemicals. The main ingredients are various hydrocarbons, some of which can cause cancer (eg. the PAHs or polycyclic aromatic hydrocarbons); other hydrocarbons can cause skin and airway irritation. There are also certain volatile hydrocarbons called VOCs (volatile organic compounds) which can cause cancer and neurologic and reproductive harm. Oil also contains traces of heavy metals such as mercury, arsenic, and lead.
Dr. Solomon’s excellent blog series describes the acute health effects of exposure to oil as including headaches, dizziness, nausea, vomiting, irritation of the eyes and throat, and difficulty breathing. In addition, the off-shore burning of oil, one of the strategies being used to reduce the massive spill, could harm human health. Depending on the prevailing winds and other weather-related conditions, particulates of oil and those from the combustion of the oil could exacerbate respiratory problems throughout the region. Anywhere that oil can be smelled is a place where oil particles are being inhaled. This threatens the health of pregnant women and those with respiratory disease, who are particularly vulnerable to the health effects of these toxic chemicals, as well as the workers and volunteers working near the oil, who are going to be disproportionately exposed to the chemicals.
There are long-term health concerns as well. Even after the spill has been staunched, fish and shellfish may carry the contaminants in their bodies for decades. “Contaminants in oil can persist for years and accumulate in the food chain,” Dr. Solomon writes, “causing elevated cancer risks or neurological risks from exposure to heavy metals such as mercury.” We know that mercury in fish is already the primary source of human exposure to this neurotoxic chemical, due to coal combustion emissions settling on waterways and being taken up by wildlife. The future implications of the additional mercury and other heavy metals in this important seafood system are unknown.
In addition to the human health implications of exposure to the oil itself, there are concerns about the widespread use of chemical dispersants over the oil slick in the Gulf, which act to break up the oil into tiny pieces. The dispersants do not make the oil go away, but they break it up into tiny blobs so that it is not as harmful to wildlife and so that it is more accessible to being broken down by bacteria. At least that’s the thinking behind what is turning out to be a massive, uncontrolled experiment in the use of these chemicals, which are themselves potentially toxic.
As the New York Times reported today, 160,000 gallons of the dispersant have already been sprayed on the water surface and an additional 6,000 gallons have been injected directly into the leak itself, thousands of feet underwater. These chemicals are poisons, used only in a grim calculation that their effects on the ecosystem can’t be worse than the effects of the unchecked oil spill.
It’s a thicket of tough choices, made worse by the fact that we don’t know exactly what is in these chemicals. The ingredients are claimed as “proprietary information” by Nalco Company, which makes Corexit, the main dispersant being used in the Gulf. We don’t know the ingredients of these potentially hazardous chemicals, so there’s a lot about the health risks that we don’t know. Meanwhile, wildlife, workers, and volunteers are being exposed directly to the substances. The ocean is large, and the chemicals will be diluted quickly. But will they have long-term effects on the fish and shellfish? Will they accumulate in the animals and move through the food web? Are people likely to be exposed to these chemicals or their breakdown products in years to come? We don’t know.
Setting Health-Protective Policies
If the idea of proprietary business information sounds familiar, it is. For years now, PSR has been calling for the reform of our nation’s chemical regulatory system, which currently allows the chemical industry to shield basic information from the public under the guide of protecting proprietary information. We think this loophole is detrimental to the health and wellbeing of Americans – and we are working to educate people about the health implications. As a member of the Safer Chemicals, Healthy Families coalition, we support the regulatory changes laid out in the Safe Chemicals Act of 2010, introduced by Senator Lautenberg in April. The Gulf oil spill is just one example of how a stronger chemical regulatory system will be better for the health of all Americans.
And lest you doubt that chemicals in the environment can have adverse effects on human health, I point you to the report released today by the President’s Cancer Panel. The panel concluded that the contribution of environmental chemicals to cancer risk is underestimated, and it criticizes the U.S. approach to such chemicals as reactionary as opposed to precautionary. Our current regulatory regime presumes chemicals to be safe unless strong evidence emerges to the contrary; a precautionary approach would take preventive action when there is uncertainty about potential harm.
In the case of the Gulf oil spill, the lessons on a precautionary approach are multiple. A precautionary approach to chemical regulation would ensure that the chemical dispersants being used so widely are safe and that their ingredients are known. A precautionary approach to energy policy would ensure that off-shore drilling, with its unknown risks and potentially grave health effects, is phased out of our energy portfolio. And a precautionary approach to climate change would ensure that we move aggressively toward clean, renewable energy sources, and away from the fossil fuels that are harmful to our health and the environment. We need safer alternatives. Clean, renewable energy is the only medically defensible way forward.