How climate change can affect our health within 30 years

WASHINGTON - Scientists have demonstrated how climate change could increase exposure and risk of human illness originating from ocean, coastal and Great Lakes ecosystems, with some studies projecting impacts to be felt within 30 years.

Using cutting-edge technologies to model future ocean and weather patterns, Stephanie Moore, with NOAA’s West Coast Center for Oceans and Human Health and her partners at the University of Washington, are predicting longer seasons of harmful algal bloom outbreaks in Washington State’s Puget Sound.

The team looked at blooms of Alexandrium catenella, more commonly known as “red tide,” which produces saxitoxin, a poison that can accumulate in shellfish. If consumed by humans, it can cause gastrointestinal and neurological symptoms including vomiting and muscle paralysis or even death in extreme cases.

“Changes in the harmful algal bloom season appear to be imminent and we expect a significant increase in Puget Sound and similar at-risk environments within 30 years, possibly by the next decade,” said Moore.

“Our projections indicate that by the end of the 21st century, blooms may begin up to two months earlier in the year and persist for one month later compared to the present-day time period of July to October.”

Researchers at the University of Georgia, a NOAA Oceans and Human Health Initiative Consortium for Graduate Training site, looked at how global desertification-and the resulting increase in atmospheric dust based on some climate change scenarios-could fuel the presence of harmful bacteria in the ocean and seafood.

Desert dust deposition from the atmosphere is considered one of the main contributors of iron in the ocean, has increased over the last 30 years and is expected to rise based on precipitation trends in western Africa. Iron is limited in ocean environments and is essential to most forms of life.

In a study conducted in collaboration with the U.S. Geological Survey, Erin Lipp, and graduate student Jason Westrich demonstrated that the sole addition of desert dust and its associated iron into seawater significantly stimulates growth and persistence of Vibrios, a group of ocean bacteria that occur worldwide and can cause gastroenteritis and infectious diseases in humans.

“Within 24 hours of mixing weathered desert dust from Morocco with seawater samples, we saw a 10-1000-fold growth in Vibrios, including one strain that could cause eye, ear, and open wound infections, and another strain that could cause cholera,” said Lipp.

The research was presented at the annual meeting of the American Association for the Advancement of Science (AAAS). (ANI)