Public comment sought on proposed standards
FRISCO — When BP’s failed Deepwater Horizon drilling rig spewed millions of gallons of crude oil in the Gulf of Mexico nearly five years ago, the emergency response included the massive use of oil dispersants, chemicals meant to break up potential oil slicks before they reached the shoreline.
But numerous studies since then have shown that the dispersants — and especially the mix of oil and dispersants — was probably far more toxic to some organisms than anyone knew.
“During the Deepwater Horizon response, chemical dispersants were used without prior understanding of their impact on the health of the people and the animals that depend on the Gulf of Mexico – many of these impacts continue today,” said Marylee Orr, Executive Director of Louisiana Environmental Network.
About 1.84 million gallons of chemical oil dispersants were released into the Gulf of Mexico during the Deepwater Horizon disaster despite widespread recognition that little was known about the health and environmental effects of applying such massive quantities of these chemicals.
One laboratory study found that the oil-dispersant mix was up to 52 times more toxic to tiny rotifers, microscopic grazers at the base of the Gulf’s food chain.
Other research found a dramatic change in the composition of microbial communities on some Gulf beaches, while another study found traces of a toxic blend of oil and dispersants present in the surf line, where swimmers and surfers could be exposed.
Basically, the studies found that the mixture of oil and dispersant is more easily absorbed by organisms, raising the question of whether the benefits of using dispersant are enough to offset the negative effects.
The Deepwater Horizon spill marked the first time dispersant was used in such massive quantities, being mixed directly with the oil spewing out of the broken well.
Now the EPA says it’s ready to change some of its rules guiding the use of dispersants, in part to address questions raised by the Deepwater Horizon disaster.
The changes include:
- New and revised product toxicity and efficacy test methodologies for dispersants, and other chemical and biological agents;
- New toxicity and efficacy criteria;
- Additional human health and safety information requirements from manufacturers;
- Revised area planning requirements for chemical and biological agent use authorization; and
- New dispersant monitoring requirements when used on certain oil discharges.
“Our emergency officials need the best available science and safety information to make informed spill response decisions when evaluating the use of specific products on oil discharges,” said Mathy Stanislaus, assistant administrator for EPA’s Office of Solid Waste and Emergency Response.
“Our proposed amendments incorporate scientific advances and lessons learned from the application of spill-mitigating substances in response to oil discharges and will help ensure that the emergency planners and responders are well-equipped to protect human health and the environment,” Stanislaus said.
According to the EPA, dispersant manufactures will be able to use a new, well-tested and peer reviewed laboratory method for determining the effectiveness of their dispersant on two types of crude oils at two temperatures measured against proposed performance criteria.
The agency is also proposing an aquatic toxicity threshold such that products that meet both the performance and toxicity criteria will offer greater performance at less environmental impact.
EPA is also proposing product chemical ingredient disclosure options and new evaluation criteria and a process for removing products from the Product Schedule.
The agency will accept public comments on the proposal for 90 days following publication in the Federal Register. More details on the proposal are at this EPA web page.