Environmental Factor, September 2005, National Institute of Environmental Health Sciences
NIEHS-Funded Research Graces the Cover of Science News
By Colleen Chandler
Five years ago, NIEHS decided to commit $6.6 million to research on red-tide toxins. That research is making quite a splash in the biomedical research community.
According to a cover story in the July 22 issue of Science News, the latest findings have been presented in more than a dozen papers and presentations. Perhaps the most visible result of red tide is in the numbers of dead manitees and dolphins showing up on beaches where red tide blooms are evident. Among the surprises researchers found: red tide toxins can be beneficial to human health.
The toxin, it turns out, actually turns the water greenish-yellow or brown, not red. But it is the invisible, airborne irritants that most affect people.
Principal Investigator Dan Baden heads the Center for Marine Science at the University of North Carolina at Wilmington. He and his team have been studying red tide and the process that produces toxins, called brevetoxins, through photosynthesis. The toxins kill fish, contaminate shellfish, and irritate the respiratory system of mammals, including humans.
Baden and his team have discovered that neurotoxicity is not the only way red tide can cause health problems. The Science News articles said red tide creates between nine and 13 toxins. Waves release the toxins in the water, turning the coastal waters into toxic soup, the article said.
However, an unexpected surprise came when researchers discovered potentially helpful effects of the toxins. They are now focusing part of their work on harnessing these toxins to treat lung diseases. One of the toxins may aid in the treatment of cystic fibrosis by clearing mucus from the lungs.
Baden presented his research at the Society of Toxicology Meeting in New Orleans in March. Brevetoxins accumulate in rodent cerebellums, which control cognitive function, breathing and muscles, he said. If the toxins have the same effect on manitees, that could explain their disorientation and seeming inability to swim out of the toxic water. Tainted fish are probably the reasons dolphins are dying, researchers speculated. Even low levels of the toxins can kill fish.