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Dermal exposure to weathered MC252 crude oil results in echocardiographically identifiable systolic myocardial dysfunction in double-crested cormorants (Phalacrocorax auritus)
Ecotoxicology and Environmental Safety (2017)
  • Kendal E Harr, Urika LLC
  • M Rishniw, Veterinary Information Network
  • Tracy L Rupp, Abt Associates
  • Dave Cacela, Abt Associates
  • Karen Dean, Abt Consulting
  • Brian S Dorr
  • Katie C Hanson-Dorr
  • Kate Healy, USFWS
  • Katherine E Horak, USDA National Wildlife Research Center
  • Jane E Link, Michigan State University
  • Drury R. Reavill
  • Stephen j Bursian, Michigan State University
  • Fred L Cunningham, USDA National Wildlife Research Center

During the Deepwater Horizon Natural Resource Damage Assessment, gross morphologic cardiac abnormalities,
including softer, more distensible musculature, were noted upon gross necropsy in hearts from
laughing gulls and double-crested cormorants exposed to weathered MC252 crude oil. A species specific,  echocardiographic technique was developed for antemortem evaluation of function that was
used to evaluate and better char- acterize cardiac dysfunction. Control (n=12) and treated (n=13) cormorant groups of similar sex-ratio and ages were dermally treated with approximately 13 ml of water or weathered MC252 crude oil, respectively, every 3 days for 6 dosages. This resulted in a low to moderate external exposure. Upon visualization and clinical as- sessment of the hearts of all test subjects, comprehensive diagnostic cardiographic measurements were taken twice, prior to oil application and after a 21 day dermal oil exposure. Oil-treated birds showed a decrease in cardiac systolic function, as characterized by an increased left ventricular internal dimension-systole and left ventricular stroke volume as well as concurrent decreased left ventricular ejection fraction and left ventricular fractional shortening when compared to both control birds’ and the treated birds’ time zero  values.  These changes are indicative of a possible dilative cardiomyopathy induced by oil exposure, although further eluci- dation of possible collagen damage is recommended. Arrhythmias including tachycardia in two treated birds and bradycardia in all treated birds were documented, indicating further clinically significant abnormalities induced by MC252 oil that warrant further investigation. A statistically significant
increase in free calcium concentration, important to muscular and neurologic function in treated birds was also noted. This study documents that weathered MC252 oil caused clinically significant cardiac dysfunction that could result in mortality and decrease recruitment.
  • Arrhythmia,
  • Naphthalene,
  • Cardiomyopathy,
  • Petroleum crude oil,
  • Polycyclic aromatic hydrocarbons (PAH),
  • Deepwater Horizon oil spill
Publication Date
Winter December, 2017
Citation Information
Kendal E Harr, M Rishniw, Tracy L Rupp, Dave Cacela, et al.. "Dermal exposure to weathered MC252 crude oil results in echocardiographically identifiable systolic myocardial dysfunction in double-crested cormorants (Phalacrocorax auritus)" Ecotoxicology and Environmental Safety Vol. 146 (2017) p. 76 - 82
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