Washington, DC (February 6, 2014) — A chemical that can accumulate in seafood and is known to cause brain damage is also toxic to the kidneys, but at much lower concentrations. The findings, which come from a study appearing in an upcoming issue of the Journal of the American Society of Nephrology (JASN), suggest that officials may need to reconsider what levels of the toxin are safe for human consumption.
The world's oceans contain algae that produce certain chemicals that can be harmful to humans and other living creatures. Many of these chemicals are considered neurotoxins because they cause damage to the brain. The neurotoxin domoic acid, also called "Amnesic Shellfish Poisoning," is a very stable, heat resistant toxin that is becoming more prominent in coastal regions, likely due to environmental changes. It can accumulate in mussels, clams, scallops, and fish, and the FDA has set a legal limit of domoic acid in seafood based primarily on its adverse neurological effects.
Because domoic acid is cleared from the body by the kidneys, P. Darwin Bell, PhD, Jason Funk, PhD (Medical University of South Carolina), and their colleagues looked to see if the toxin might also have detrimental effects on these organs. By giving mice varying doses of domoic acid and the assessing animals' kidney health, the team found that the kidney is much more sensitive to this toxin than the brain.
"We have found that domoic acid damages kidneys at concentrations that are 100 times lower than what causes neurological effects," said Dr. Bell. "This means that humans who consume seafood may be at an increased risk of kidney damage possibly leading to kidney failure and dialysis."
While the findings need to be verified in humans, the researchers would like to see increased awareness and monitoring of domoic acid levels in all seafood. They say that the FDA may also need to reconsider the legal limit of domoic acid in food due to its kidney toxicity.
Study co-authors include Michael Janech, PhD, Joshua Dillon, John Bissler, MD, and Brian Siroky, PhD.
Disclosures: John Bissler, MD receives grant funding and honoraria from Novartis and has participated in its advisory boards. This study was supported, in part, by funds from the NIH, VA, DOD, and Dialysis Clinic, Inc.
The article, entitled "Characterization of Renal Toxicity in Mice Administered the Marine Biotoxin Domoic Acid," will appear online at http://jasn.asnjournals.org/ on February 6, 2014.
The content of this article does not reflect the views or opinions of The American Society of Nephrology (ASN). Responsibility for the information and views expressed therein lies entirely with the author(s). ASN does not offer medical advice. All content in ASN publications is for informational purposes only, and is not intended to cover all possible uses, directions, precautions, drug interactions, or adverse effects. This content should not be used during a medical emergency or for the diagnosis or treatment of any medical condition. Please consult your doctor or other qualified health care provider if you have any questions about a medical condition, or before taking any drug, changing your diet or commencing or discontinuing any course of treatment. Do not ignore or delay obtaining professional medical advice because of information accessed through ASN. Call 911 or your doctor for all medical emergencies.
Founded in 1966, and with more than 14,000 members, the American Society of Nephrology (ASN) leads the fight against kidney disease by educating health professionals, sharing new knowledge, advancing research, and advocating the highest quality care for patients.
AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.