Study: Gulf oil spill cleanup workers show blood abnormalities

A new study reports that workers exposed to crude oil and dispersants used during the Gulf oil spill cleanup display significantly altered blood profiles, liver enzymes, and somatic symptoms compared to an unexposed control group. Investigators found that platelet counts were significantly decreased in the exposed group, while both hemoglobin and hematocrit levels were notably increased. Their findings, reported in The American Journal of Medicine, suggest that oil spill cleanup workers are at risk for developing hepatic or blood-related disorders.

In April 2010, Deepwater Horizon, an offshore drilling rig owned by British Petroleum (BP) exploded, spewing over 200 million gallons of oil into the Gulf of Mexico. In order to break down the oil slick, BP used nearly 2 million gallons of dispersants like COREXIT, and an estimated 170,000 workers participated in the cleanup effort. Currently, COREXIT is banned in the United Kingdom because of its potential risk to cleanup workers.

While other studies have identified a relationship between oil spills, dispersants, and human health, this new research from the University Cancer and Diagnostic Centers, Houston, TX, conducted by Mark A. D’Andrea, MD, FACRO, and G. Kesava Reddy, PhD, MHA, focuses primarily on the link between oil spill exposure and hematologic and hepatic functions in subjects who had participated in the oil spill cleanup operation. The investigators looked at a total of 247 subjects between January 2010 and November 2012, with 117 subjects identified as exposed to the oil spill and dispersants by participating in the cleanup over the duration of three months. The unexposed control group of 130 subjects was comprised of people living at least 100 miles away from the Gulf coast of Louisiana.

Using medical charts, demographic and clinical records, the team reviewed specific data points such as white blood cell (WBC) counts, platelet counts, hemoglobin, hematocrit, blood urea nitrogen (BUN), creatinine, serum beta-2 microglobulin, alkaline phosphatase (ALP), aspartate amino transferase (AST), and alanine amino transferase (ALT) for both groups.

While no significant differences were noted in the WBC counts of the two groups, the study did find that platelet counts were notably decreased in the oil spill exposed group. Also, BUN and creatinine levels were substantially lower in the exposed group, while hemoglobin and hematocrit levels were increased compared to the unexposed subjects. Furthermore, considered indicators of hepatic damage, the serum ALP, AST, and ALT levels in the exposed subjects were also elevated, suggesting that the exposed group may be at a higher risk for developing blood-related disorders.

"Phosphatases, amino transferases, and dehydrogenases play critical roles in biological processes. These enzymes are involved in detoxification, metabolism, and biosynthesis of energetic macromolecules that are important for different essential functions," says lead investigator Dr. Mark A. D’Andrea. "Alterations in the levels of these enzymes result in biochemical impairment and lesions in the tissue and cellular function."

Participants also reported somatic symptoms, with headache reported most frequently, followed by shortness of breath, skin rash, cough, dizzy spells, fatigue, painful joints, night sweats, and chest pain. "The health complaints reported by those involved in oil cleanup operations are consistent with the previously reported studies on major oil spills. However, the prevalence of symptoms appears to be higher in the present study compared with the earlier findings of other investigators," add Dr. D’Andrea and Dr. Reddy.

The investigators acknowledge that the lack of pre-disaster health data on the subjects involved in the study is the greatest limiting factor; however, the data collected have shown significant health effects on the cleanup workers.

"To our knowledge, no previous study has explored the effects of the oil spill specifically assessing the hematological and hepatic functions in oil spill cleanup workers," explain the investigators. "The results of this study indicate that oil spill exposure appears to play a role in the development of hematologic and hepatic toxicity. However, additional long-term follow-up studies are required to understand the clinical significance of the oil spill exposure."

-----------------------------------------------------------------------------
Are you concerned about chemical exposure? AllerAir specializes in air purifiers for chemicals and odors. Using the same technology found in military gas masks, AllerAir's deep-bed carbon filters remove the pollutants other air purifiers leave behind. Connect with us to learn more www.allerair.com.

Deepwater Horizon Debris Likely Source of Gulf of Mexico Oil Sheens

Photo: freedigitalimages.net

A chemical analysis of oil sheens found floating recently at the ocean’s surface near the site of the Deepwater Horizon disaster indicates that the source is pockets of oil trapped within the wreckage of the sunken rig. Both the Macondo well and natural oil seeps common to the Gulf of Mexico were confidently ruled out.

Researchers from Woods Hole Oceanographic Institution (WHOI) and the University of California, Santa Barbara (UCSB) used a recently-patented method to fingerprint the chemical makeup of the sheens and to estimate the location of the source based on the extent to which gasoline-like compounds evaporated from the oil sheens. The study was published online this week in Environmental Science & Technology.

The oil sheens were first reported to the United States Coast Guard by BP in mid-September 2012, raising public concern that the Macondo well, which was capped in July 2010, might be leaking.

“It was important to determine where the oil was coming from because of the environmental and legal concerns around these sheens. First, the public needed to be certain the leak was not coming from the Macondo well, but beyond that we needed to know the source of these sheens and how much oil is supplying them so we could define the magnitude of the problem,” said WHOI chemist Chris Reddy.

When oil sheens appear on the ocean surface, how do researchers determine where the oil is coming from? Every oil sample contains chemical clues pointing to the reservoir it came from, allowing scientists to compare it to other samples to determine if they share a common source. The lead scientists Chris Reddy (WHOI) and Dave Valentine (UCSB) were aptly prepared to investigate these sheens. They have worked on the Deepwater Horizon for much of the last three years, investigating a wide range of problems from the composition of the oil, detection of subsurface plumes, the biodegradation of the oil, the fate of the dispersants, and the chemical transition from floating oil slicks to sunken tar balls.

“Because of our ongoing funding from the National Science Foundation, we were prepared to interrogate the source of mysterious oil sheens in the Gulf of Mexico,” said Valentine. “We’ve been exploring new ways to do this for several years in the context of natural seeps and this event provided us an opportunity to apply our fundamental advances to a real-world problem. This is a classic case where fundamental science finds a real world application.”

This research analyzed 14 sheen samples they skimmed from the sea surface during two trips to the Gulf of Mexico. Using comprehensive two-dimensional gas chromatography (GCxGC), a technique developed in Reddy’s lab, the researchers first confirmed the sheens contained oil from the Macondo well. But the sheen samples also contained trace amounts of “olefins”—industrial chemicals that are used in drilling operations—compounds that were absent from the sample taken directly from the Macondo well. The presence of “olefins” provided a fingerprint for the sheens that the authors could compare to the library of samples they had analyzed over the past three years.

The “olefins” are not found in crude oil and their uniform distribution in the sheens indicated that the Macondo well was unlikely to be the source. The team surmised that the sheens must be coming from equipment exposed to olefins during drilling operations. Reddy’s lab holds a patent on measuring olefins in crude oils.

“The occurrence of these man-made olefins in all of our sheen samples points to a single main source which contains both Macondo oil and lesser amounts of the drilling fluids that harbor the olefins,” said Valentine. “This pointed us to the wreckage of the rig, which was known to have both, as the most likely source for the sheens.”

It also meant the olefins could be used by the team as a fingerprint in the search for the source of the leak.

The research team compared the sheen samples to other field samples, some of which they expected would contain olefins and some they thought would not. The reference samples included two pieces of debris from the Deepwater Horizon, found floating in early May 2010, as well as oil collected by BP in October 2012 during an inspection of the 80-ton cofferdam that had been abandoned at the sea floor after its use in a failed attempt to cover the Macondo well in 2010.

The team’s GCxGC analysis of BP’s cofferdam samples definitively showed the cofferdam was not the sole source of the leak – there were no olefins present. Prior to the analysis, the cofferdam had become the prime suspect as the source when BP found small amounts of oil leaking from the top of the cofferdam. BP acquired oil samples from this leak point before sealing the leak, thinking they had resolved the problem. However, the sheens on the sea surface persisted, and the lack of olefins pointed to another source entirely.

When Reddy and Valentine compared the chemical makeup of the sheens with Deepwater Horizon debris found floating in 2010, they found a match. That debris, which came from the rig itself, was coated with oil and contaminated with drilling mud olefins.

”The ability to fingerprint synthetic hydrocarbons allowed us to crack this case. We were able to exclude a number of suspects and match the olefin fingerprint in the new oil slicks to that of the wreckage from the sunken rig,” said Valentine.

The chemical analysis also told researchers which sheens had surfaced more recently than others, allowing them to reconstruct a trajectory for local ocean currents that pointed back to the source of the oil. By looking for sheens that showed the least amount of evaporation, they determined that oil surfaced closer to the Deepwater Horizon wreckage than the cofferdam site.

To explain how the oil might be trapped and released from the wreckage, the scientists point out that when the Deepwater Horizon rig sank, it was holding tanks containing hundreds of barrels of a mixture of drilling mud and oil. Over time, corrosive seawater can create small holes for oil to slowly escape to the surface. The researchers suspect that the containers on the Deepwater Horizon rig holding entrapped oil may be the source of the recent oil sheen.

“This study shows that drilling mud olefins are a powerful forensic tool to investigate the source of oil sheens,” the authors wrote.

In the process of their research, Reddy and Valentine operated with transparency, alerting the government and BP to their research plans. They believe this fostered a collegial relationship that ultimately improved their research. Throughout the effort to find the source of the oil, there was keen interest in the research both by BP and federal agencies; all stakeholders sought to determine the source of the oil, though each required a different level of certainty about the results, and each had different questions to answer. Reddy and Valentine required great certainty in their results before publishing them, but recognized that their preliminary data could be useful to others who could use it to take immediate action with less certainty.

“We had a fruitful exchange and developed a collegial relationship with both BP and the government. Both provided us with data, and in turn we gave them a preview of our findings with no strings attached,” said Valentine.

At the end of the day, Reddy said, “This is a good study, but the long lasting impacts of this effort were highlighting that academia can play a useful role during a crisis. We can be unbiased and collaborative without losing our integrity. What is lost on many of our colleagues is that interacting with representatives of the government and BP provided advice and input that improved our research. This is a win-win.”

In addition to Reddy and Valentine, the research team consisted of WHOI postdoctoral investigator Christoph Aeppli, UCSB Postdoctoral Scholar Matthias Kellermann, and Robert K. Nelson, a member of the WHOI technical staff.

This research was funded by the National Science Foundation, the Gulf of Mexico Research Initiative DEEP-C Consortium, Woods Hole Oceanographic Institution, and the Swiss National Science Foundation Postdoctoral Fellowship.

Health defects found in fish exposed to Deepwater Horizon oil spill

Photo: Victor Habbick/freedigitalphotos.net

Crude oil toxicity continued to sicken a sentinel Gulf Coast fish species for at least more than a year after the Deepwater Horizon oil spill in the Gulf of Mexico, according to new findings from a research team that includes a University of California, Davis, scientist.

With researchers from Louisiana and South Carolina, the scientists found that Gulf killifish embryos exposed to sediments from oiled locations in 2010 and 2011 show developmental abnormalities, including heart defects, delayed hatching and reduced hatching success. The killifish is an environmental indicator species, or a “canary in the coal mine,” used to predict broader exposures and health risks.

The findings, posted online in advance of publication in the journal Environmental Science and Technology, are part of an ongoing collaborative effort to track the impacts of the Deepwater Horizon oil spill on Gulf killifish populations in areas of Louisiana that received heavy amounts of oil.

Other species that share similar habitats with the Gulf killifish, such as redfish, speckled trout, flounder, blue crabs, shrimp and oysters — may be at risk of similar effects.

“These effects are characteristic of crude oil toxicity,” said co-author Andrew Whitehead, an assistant professor of environmental toxicology at UC Davis. “It’s important that we observe it in the context of the Deepwater Horizon spill because it tells us it is far too early to say the effects of the oil spill are known and inconsequential. By definition, effects on reproduction and development — effects that could impact populations — can take time to emerge.”

Killifish are abundant in the coastal marsh habitats along the Gulf Coast. Though not fished commercially, they are an important forage fish and a key member of the ecological community. Because they are nonmigratory, measurements of their health are indicative of their local environment, making them an ideal subject for study.

The researchers collected Gulf killifish from an oiled site at Isle Grande Terre, La., and monitored them for measures of exposure to crude oil. They also exposed killifish embryos in the lab to sediment collected from oiled sites at Isle Grande Terre within Barataria Bay in Louisiana.

“Our findings indicate that the developmental success of these fish in the field may be compromised,” said lead author Benjamin Dubansky, who recently earned his Ph.D. from Louisiana State University.

Whitehead said the report’s findings may predict longer-term impacts to killifish populations. However, oil from the Deepwater Horizon spill showed up in patches, rather than coating the coastline. That means some killifish could have been hit hard by the spill while others were less impacted.

Whitehead said it is possible that some of the healthier, less impacted killifish could buffer the effects of the spill for the population as a whole.

The research was supported by grants from the National Science Foundation, the Gulf of Mexico Research Initiative and the National Institutes of Health.

The other researchers in the study are Fernando Galvez, associate professor of biological sciences at Louisiana State University; and Charles D. Rice, professor of biological sciences at Clemson University in Clemson, South Carolina. The researchers have tracked the impact of the oil on killifish since the Deepwater Horizon spill occurred in April 2010.

 

------------------------------------------------------------

For more stories on health, pollution, chemical exposure and improving your indoor air quality visit www.allerair.com or call to speak to an air quality expert about improving the air in your home 1-888-852-8247.