It's hard to believe that the Deepwater Horizon incident, which discharged over 200 million gallons of oil into the Gulf of Mexico, happened six years ago. What's not hard to believe is that the environmental health implications of the spill are stubbornly lingering.
Gulf residents of variety of species are paying a high price for it -- so high that litigation against BP for its role in the spill, officially deemed "negligent," is likely to continue for decades as people fight to get help with ongoing medical expenses.
Last year, the National Oceanic and Atmospheric Administration announced that the spill was linked to an uptick in dolphin deaths, illustrating that this unprecedented release of petroleum products in the Gulf had a lasting health impact for animals.
Similarly, abnormalities in heart development among fish have also been connected to Deepwater Horizon exposure. Part of the problem is that sediments remain coated in oil and sludge. Because it was impossible to clean up every drop of crude from the Gulf, the oil that settled to the bottom continues to interfere with the embryonic development of a range of fish species.
But humans aren't doing too well either.
In the aftermath of the spill, people were exposed both to crude petroleum and to Corexit, a chemical dispersant used in unprecedented volumes during the cleanup.
Subsequent research has shown that in addition to having some hazardous health effects on its own, the combination of Corexit and the type of crude spilled during the Deepwater Horizon incident packs a hefty punch for marine animals.
In the weeks following the spill, first responders reported symptoms like rashes, respiratory problems, headaches, seizures and depression. In response to the complains, agencies closely monitored these individuals.
As the years went by, enough significant health problems arose for a class action lawsuit against BP. The company eventually agreed to a settlement that included the potential for filing future claims related to exposure.
Those "future claims" are ringing the doorbell now.
And they're not just coming from first responders. Those exposed to oil in other ways, including from living and working around the areas where oil washed ashore and handling clothing and tools used by first responders, are developing persistent health problems.
While it's too early to definitively link all their reported symptoms to the Deepwater Horizon disaster, the individuals claim that conditions like pneumonia, leukemia, infertility, nerve damage, cognitive disabilities and endocrine disorders are a result of their exposure to oil and solvents.
These kinds of health issues have been connected to other oil spills in the past, but BP is dragging its feet on helping with health expenses, which can be ruinously expensive in the the United States.
These lingering problems highlight the fact that the problems associated with an oil spill don't end when the last news camera goes away and the last containment boom is pulled up.
People in the Gulf will be dealing with Deepwater Horizon for decades, especially those who live in low-income communities. Given this reality, the government is conducting longitudinal studies on people who were exposed to analyze potential long-term health impacts.
While that research may help victims of the next big oil spill, it's hollow for Deepwater Horizon survivors who lost their livelihoods -- and their health -- to the disaster.