Southeast
Photos by Shirley Woolaway | Nick Penniman presented information on Blue-Green Algae and Red Tide.

Blue-Green Algae and Red Tide: How Harmful Are They?

A discussion on Climate Change by Nick Penniman, long involved in civic and environmental advocacy in Collier County, brought not only clarity on the subject to his listeners, but also a sense of urgency about the need to address what’s happening in our local area. Penniman spoke recently to members of the Naples League of Women Voters and guests with a presentation titled, “Red Tide, Blue-Green Algae and Human Health.”

Perhaps many of us have been affected by red tide, noticing some physical symptoms like coughing and other respiratory distress and wonder how harmful it is. According to Penniman, recent medical research shows about 80% of those with asthmatic conditions are affected by red tide, but that symptoms generally are not long-lasting once away from the source of the problem.

Red tide, he explained, is a saltwater algae, whirling whip, that is single-celled and tiny with a wide tolerance for salinity and temperature with a diet cycle know as a “grazer.” When its cells are ruptured, their aerosolized polyether toxin is released as Brevetoxin. While there is currently no research connecting red tide to long-term human health issues, Penniman said shellfish and sea life are not so fortunate. Shellfish poisoning is common, as is the death of finfish that ingest through their gills. Manatee studies indicate more severe implications. One study showed lower lymphocyte counts and necropsy while a second study indicated manatees develop neuromuscular problems with higher levels of Brevetoxin from red tide in the liver, kidney, stomach and brain, which is caused from eating seagrass.

One slide showed sources of the problem as nutrients from the Mississippi River’s dead zone, coastal runoff, dissolved oxygen created by die-offs and an up-welling wind accounting for red tide issues on the Gulf coast.

Read the full story here.