Deepwater Horizon crude oil impacts the developing hearts of large predatory pelagic fish
John P. Incardonaa,1, Luke D. Gardnerb, Tiffany L. Linboa, Tanya L. Browna, Andrew J. Esbaughc, Edward M. Magerc, John D. Stieglitzc, Barbara L. Frencha, Jana S. Labeniaa, Cathy A. Laetza, Mark Tagala, Catherine A. Sloana, Abigail Elizurd, Daniel D. Benettic, Martin Grosellc, Barbara A. Blockb, and Nathaniel L. Scholza
Edited by Karen A. Kidd, University of New Brunwsick, Saint John, BC, Canada, and accepted by the Editorial Board February 24, 2014 (received for review November 6, 2013)
Significance The 2010 Deepwater Horizon (MC252) disaster in the northern Gulf of Mexico released more than 4 million barrels of crude oil. Oil rose from the ocean floor to the surface where many large pelagic fish spawn. Here we describe the impacts of field-collected oil samples on the rapidly developing embryos of warm-water predators, including bluefin and yellowfin tunas and an amberjack. For each species, environmentally relevant MC252 oil exposures caused serious defects in heart development. Moreover, abnormalities in cardiac function were highly consistent, indicating a broadly conserved developmental crude oil cardiotoxicity. Losses of early life stages were therefore likely for Gulf populations of tunas, amberjack, swordfish, billfish, and other large predators that spawned in oiled surface habitats.
The Deepwater Horizon disaster released more than 636 million L of crude oil into the northern Gulf of Mexico. The spill oiled upper surface water spawning habitats for many commercially and ecologically important pelagic fish species. Consequently, the developing spawn (embryos and larvae) of tunas, swordfish, and other large predators were potentially exposed to crude oil-derived polycyclic aromatic hydrocarbons (PAHs). Fish embryos are generally very sensitive to PAH-induced cardiotoxicity, and adverse changes in heart physiology and morphology can cause both acute and delayed mortality. Cardiac function is particularly important for fast-swimming pelagic predators with high aerobic demand. Offspring for these species develop rapidly at relatively high temperatures, and their vulnerability to crude oil toxicity is unknown. We assessed the impacts of field-collected Deepwater Horizon (MC252) oil samples on embryos of three pelagic fish: bluefin tuna, yellowfin tuna, and an amberjack. We show that environmentally realistic exposures (1–15 μg/L total PAH) cause specific dosedependent defects in cardiac function in all three species, with circulatory disruption culminating in pericardial edema and other secondary malformations. Each species displayed an irregular atrial arrhythmia following oil exposure, indicating a highly conserved response to oil toxicity. A considerable portion of Gulf water samples collected during the spill had PAH concentrations exceeding toxicity thresholds observed here, indicating the potential for losses of pelagic fish larvae. Vulnerability assessments in other ocean habitats, including the Arctic, should focus on the developing heart of resident fish species as an exceptionally sensitive and consistent indicator of crude oil impacts.
In conjunction with previous studies, the findings here demonstrate that the response of teleost embryos to petroleumderived PAHs in both the laboratory and the field is highly conserved among species tested thus far. Tunas and amberjacks develop at higher water temperatures, and yet they display heart failure and other abnormalities that are remarkably similar to those previously reported for species, such as herring and salmon, which develop at very cold temperatures. Pacific herring were a focal species for natural resource injury assessments following the Exxon Valdez (41) (Alaskan waters) and Cosco Busan oil spills (38) (California Current). Herring early life stages exposed to both oil types, in both the field and the laboratory, developed cardiotoxic defects in the form of bradycardia (38) and pericardial edema (38, 41), with strikingly similar results to those reported here for subtropical spawning pelagic fish. The remarkably consistent morphological and physiological responses to oil across diverse fish species indicate that the core mechanisms of PAH-induced cardiotoxicity are conserved. Namely, the cardiotoxic injury stemming from embryonic exposure to crude oil observed in the scombrid and carangid species in this study is essentially identical to the response of a boreal clupeid (herring) (19), representing families that are separated by roughly 100 million y of evolution (42).
***Our findings thus have implications beyond the upper pelagic zone of the Gulf of Mexico, and are likely to be indicative of sensitivity to oil over a wider range of fish species spawning in other habitats contaminated by MC252 crude oil.
Saturday, March 22, 2014
Barge and Ship Collide off Texas City oil leaking into Galveston Bay
SEE UPDATES THROUGHOUT THIS BLOG DOWN BELOW...
Tuesday, March 25, 2014
Galveston Bay Oil Spill and the IKE dike VS Rice dike
Seafood Consumption Advisories
While Galveston Bay is an outstanding place to fish, you need to be aware of seafood consumption advisories!
The Texas Department of State Health Services (DSHS) issues seafood consumption advisories when tests on fish and shellfish indicate there is an increased risk to human health from the presence of toxic pollutants.
This map shows the seafood consumption advisories that are currently in place in the Galveston Bay system and its tributaries. There are really four areas, each having its own set of affected species.
Species Affected, and DSHS Advisories in Each Area of Concern
|Area||Species Affected||Pollutants||DSHS Advisory Number and Year Issued|
|The Houston Ship Channel and all contiguous waters north of the Fred Hartman Bridge (Hwy. 146), including the San Jacinto River below the Lake Houston Dam.||All species of fish and blue crab.||Dioxin, organochlorine pesticides and PCBs.||ADV-49 (2013)|
|Upper Galveston Bay and all contiguous waters north of a line from Red Bluff Point to Five Mile Cut Marker to Houston Point.||All catfish species, spotted seatrout, and blue crab.||Dioxin and PCBs.||ADV-50 (2013)|
|Galveston Bay system south of a line from Red Bluff Point to Five Mile Cut Marker to Houston Point, including Chocolate Bay, East Bay, West Bay, Trinity Bay, and contiguous waters.||All catfish species.||Dioxin and PCBs.||ADV-50 (2013)|
|Clear Creek upstream and west of Clear Lake.||All species of fish.||PCBs.||ADV-37 (2009)|
Consumption Advice You Should Follow for All Areas Except Clear CreekIn each of these three areas for the species listed, the following advice should be followed to decrease risks to human health:
Women of childbearing age and children under the age of 12 - DO NOT EAT ANY AMOUNT OF THE SPECIES LISTED!
Women past childbearning age and adult men - DO NOT EAT MORE THAN 8 OUNCES PER MONTH OF THE SPECIES LISTED!
Consumption Advice You Should Follow for Clear Creek Upstream of Clear LakeAll persons - DO NOT EAT ANY AMOUNT OF ANY SPECIES OF FISH!
Why Is There a Risk from Consuming the Species Listed in These Areas?When fish and crab eat, they accumulate toxic pollutants present in the prey they consume or in tainted sediment or water they filter. This process is called bioaccumulation. These toxic materials - such as organochlorine pesticides, dioxins and polychlorinated biphenyls (PCBs) - are in the environment as a result of rainfall runoff from land, spills, leaks, and improper disposal of industrial wastes.
These pollutants can especially accumulate in the fatty areas, glands, and organs of fish and crabs. As a result, some species of fish that have higher fat content - such as spotted seatrout and catfish - are listed for the advisories while others - such as red drum, black drum, croaker, and flounder - are not. However, in areas of heavy industry such as above the Lynchburg Ferry, all species of fish and blue crabs may have higher concentrations.
Exposure to organochlorine pesticides, dioxins and PCBs can cause a range of illness from skin rashes to immune system and nerve disorders to liver damage and increased risk of cancer. These toxins also pose a risk of birth defects and the development of children. The Agency for Toxic Substances & Disease Registry has more information on dioxins and PCBs.
What about Shrimp, Oysters and Clams?There are no DSHS seafood consumption advisories on shrimp, oysters, or clams. However, the harvest of molluscan shellfish (oysters, clams, and mussels) is illegal in DSHS designated “Prohibited Areas” that are in proximity to sewage treatment plant discharge locations, known contaminated areas, or other area with a high potential of containing unsafe levels of a pollutant. For example, the Houston Ship Channel/San Jacinto River upstream of Morgan’s Point is a prohibited molluscan shellfish harvest area. You can find more information and maps on the DSHS Shellfish Harvest Classification webpage.
How You Can Reduce Your Risk from These ToxinsYou should do your best to follow the advisory recommendations for consumption of the species listed in these areas. Instead of eating the same type of fish from the same waterbodies, you should fish for different species from a variety of waterbodies. You should eat smaller, younger fish that have less time to accumulate toxins in their bodies. Last, if you clean and cook the fish or crabs so that you avoid eating their fatty portions, you can reduce your risk.
The Houston-Galveston Area Council's Seafood Caution brochure has more information on the toxins and how you can prepare your catch so that your risk is decreased. DSHS has detailed information on each of these advisories. Click on the following links for PDF versions of each advisory:
DSHS Seafood and Aquatic Life Group webpage. Just click on "Fish Consumption Advisory" on the left-hand side of the page.
What is Being Done About Contaminated Seafood?The Texas Commission on Environmental Quality and the Houston-Galveston Area Council have initiated total maximum daily load (TMDL) projects for the Houston Ship Channel, San Jacinto River, Upper Galveston Bay, and Galveston Bay to pinpoint sources of dioxins and PCBs and develop a plan to reduce them. The U.S. Environmental Protection Agency is overseeing a cleanup of the San Jacinto River Waste Pits Superfund Site, one such source of dioxin to the San Jacinto River and Galveston Bay. You are encouraged to participate as a member of the public in both of these projects!
For More Information
For more information on the seafood consumption advisories, please contact:
- Galveston Bay Foundation: Scott Jones at (281) 332-3381 x209 or firstname.lastname@example.org.
- Texas Department of State Health Services: Michael Tennant at (512) 834-6757 or email@example.com.