Impact of Gulf spill uncertain

A year after the Deepwater Horizon explosion, scientists remain unsure as to the effects of the massive oil spill on the Gulf of Mexico.

Dozens of scientists surveyed in the US have ranked the “overall health” of the Gulf as almost at the same levels as before the spill, but have warned this is not the full story.

Asked to rank the environmental health of the Gulf on a scale of 1-100, the average score was revealed as 68, just three points behind that given before the spill.

However, scientists argued that while the surface of the ocean appears clean, an increase in the number of dead dolphins and turtles being washed up along the coastline during January, February and March signal that environmental impacts are not over.

Christopher D'Elia, dean at the School of the Coast and Environment at Louisiana State University said: "People had said this was an ecological Armageddon, and that did not come to pass"

Jane Lubchenco, head of the National Oceanic and Atmospheric Administration, agreed that things were “much better than people feared” but warned “the jury is out about what the end result will be. It's premature to conclude that things are good.”

D’Elia is also unconvinced as to the long-term impact. "There are cascading effects. It could be accumulation of toxins in the food chain, or changes in the food web,” he said.

The final stretch of Gulf waters closed by the Gulf of Mexico spill was finally opened by the US National Oceanic and Atmospheric Administration (NOAA) on 19 April, the day before the anniversary of the explosion that killed 11 workers and caused the release of 4.9 million barrels of oil.

The NOAA confirmed that tests on fish from the area, including tuna and swordfish, found no detectable oil or dispersant odours or flavours in the fish, and stated that chemical analysis for oil-related compounds and dispersants were well below the levels of concern.

While uncertainty remains about the long-term impacts environmental group Greenpeace has marked the anniversary of the spill by calling on the UK public to petition MPs to halt deepwater drilling in the North Sea.

However, the call comes just weeks after an Energy and Climate Change Committee investigation into the implications of the Deepwater Horizon spill concluded that there was no need to suspend deepwater drilling off the coast of the UK.