During the oil spill there were ongoing complaints of odors in coastal communities andrespiratory symptoms dominated a health survey conducted in the aftermath of the spill. In addition, a recent study documented an additional air pollutant, aerosols (or tiny particles) that formed over the oil slick that threatened clean-up workers and may have impacted onshore communities. Scientists who collected air quality samples and agencies who conducted day to day air quality monitoring need to pool all their data to see if they can get to the bottom of the following questions:
1) What was the source of the odors? A comprehensive assessment of wind patterns, odor complaints, and measured concentrations of the full suite of hydrocarbon compounds detected by coastal monitoring stations should help shed some light on this question. Further toxicological assessments may be needed to understand the link between these compounds and health impacts because the health risks associated with the full soup of chemical compounds found in oil is not well characterized.
2) To what degree did the aerosols make it onshore and at what levels? Unfortunately, the limitations in EPA’s particulate monitoring in coastal Louisiana hampers the ability to definitively answer this question. Air pollution models, or data gathered by other means, should be pursued to help understand coastal air quality threats experienced during the spill.
3) What levels of aerosols were clean-up workers exposed to out on the slick? Analyses should be pursued to link offshore air quality monitoring conducted from airplanes to any available surface level data to estimate what workers may have experienced. Regrettably, worker level monitoring for particulates was sparse and not capable of detecting the small particles created by the oil spill.
Contaminants in oil, such as polycyclic aromatic hydrocarbons (PAHs) and metals, can accumulate in the food chain contaminating seafood and leading to health risks, particularly for people who eat a lot of seafood. The large volume of oil that spewed into this productive fishery, the use of subsurface dispersant chemicals to breakdown the oil into smaller particles, and the findings of plumes of oil-spill related contaminants in thesubsurface raise questions about the extent and duration of potential seafood contamination. A long-term monitoring program is needed that includes the following:
1) Continued testing of major seafood harvesting areas
The Food and Drug Administration (FDA) relied on a total of 67 samples of shrimp to certify the safety of shrimp harvested in coastal waters from Louisiana to Florida. The last of this dedicated sampling was conducted at the end of October. Since then, FDA has not gone back and actually re-sampled these areas. Instead, FDA has relied on asurveillance program that does not provide specific information about where the samples were collected and does not provide for comprehensive ongoing tracking of contaminant levels in coastal waters. For example, only 5 surveillance samples indicate that there were collected in Mississippi (2 in October and 3 in November) – we don’t know where these shrimp were actually harvested from or what contaminant levels are like now, almost 5 months after the last samples were taken. This testing is not sufficient to determined contaminant levels over time or to certify the ongoing safety of these seafood harvesting areas. The National Oceanic and Atmospheric Administration (NOAA), has shown that this can be done. NOAA’s belated release of “post opening surveillance data” reflects samples that were taken to monitor offshore areas (in federal waters) that have been re-opened, enabling comparison of contaminant levels over time.
2) Testing for heavy metals
Metals, such as cadmium, lead, and mercury, are found in crude oil and can accumulate in marine food chains resulting in health hazards for seafood consumers. Long-term monitoring at multiple levels of the food chain (including oysters, other shellfish, and fish), is needed to evaluate the ongoing impacts of this contamination on the Gulf Coast.
3) An evaluation of threats posed by non-PAH hydrocarbons
Independent testing of seafood in Louisiana, by the Louisiana Environmental Action Network (LEAN) uncovered evidence of contamination with petroleum hydrocarbons that is not currently covered in either FDA or NOAA testing. In addition, FDA scientists concluded in their report following the Exxon Valdez oil spill that further study is needed to characterize the full toxicity of oil-related hydrocarbons - beyond PAHs - in seafood. Despite this recommendation, a comprehensive assessment was not completed and the degree to which this contamination poses a human or ecosystem health threat should be investigated.
Worker and Community Health
The spill resulted in an onslaught of health threats ranging from environmental exposures, particularly for clean-up workers, to increased anxiety and depression stemming from community disruption and economic meltdown. Layered on top of a woefully inadequate healthcare system, with a shortage of clinics and a large fraction of the population uninsured, this was a recipe for the kind of suffering being experienced by Gulf communities today. My colleague Dr. Gina Solomon has blogged more on this issue here. Studies that track and evaluate the health status of clean-up workers and coastal communities are urgently needed including:
1) Tracking oil-spill related symptoms and illnesses through state and federal registries to collect reports of oil-spill related symptoms from healthcare providers
2) Community health surveys that identify health issues and impacted areas
3) Comprehensive evaluation of health impacts experienced by clean-up workers participating in the National Institute of Environmental Health Sciences (NIEHS) Gulf Long-term Follow-up (GuLF) study.
4) A companion study to track long-term health impacts of coastal communities.
They say that “time heals” but, unaddressed health threats can fester. Plus, what we learn from this disaster can hopefully make us better prepared and help prevent the types of devastation being experienced on the Gulf Coast. One year later, the questions have piled up and the communities at the frontline of this disaster deserve answers. Let’s mark this anniversary by doing the science to ensure public health threats are identified and addressed.