Algae worse than red tide -- There's a nastier organism lurking in Florida waters
Ray Lopez Braindead Killfile the Pest
Algae worse than red tide
There's a nastier organism lurking in Florida waters
By ROSALIE SHAFFER
Special to the Herald
While "red tide" has become a household word, not as much attention has
been given to a growing problem in Florida - harmful blooms of blue-green
algae in warm, stagnant fresh waters.
These primitive, one-celled organisms can cover entire ponds and lakes
with thick green mats. But worse than the pollution and unsightliness is
their release of strong and even deadly toxins - more poisonous than
cobra venom.
"These are some of the most potent toxins we know of," said Kenneth
Hudnell, expert on freshwater algae blooms for the Environmental
Protection Agency.
The freshwater blue-green algae were the subject of a workshop Saturday
in Sarasota, sponsored by the Sarasota Department of Health and the
Sierra Club, and featuring federal, state and local specialists on the
subject.
A lot is still unknown about the many species of blue-green algae, said
Hudnell. What is known is what a major encounter with their toxins can
do. One type destroys the liver and another - a neurotoxin - causes
muscle paralysis and eventual suffocation. More frequently the toxins
cause skin rashes, respiratory, stomach and intestinal problems.
The main way Floridians come into contact with the toxins is by swimming
in contaminated waters, said Andrew Reich, coordinator of the Aquatic
Toxins Program for the Florida Department of Health. The toxins are also
ingested by eating fish or shellfish from contaminated waters, and
breathing the toxins that escape into the air as droplets.
Reich said there are no federal standards for acceptable levels of the
toxins in water supplies. However, illness from from the algae - formally
known as cyanobacteria - in public water supplies has been avoided
through water treatment.
The organisms occur all over the state, and massive blooms have occurred
in central and eastern Florida. One during the summer of 2005 covered the
St. Johns River for 100 miles. It was called "the Green Monster."
Preventing blooms works better than trying to get rid of one that already
exists, said Reich. Killing the organisms increases the amount of toxins
in the water, because when they die, the cells release all their toxins,
which persist, he said.
What causes these blooms? Both experts said they happen when conditions
are right for the algae: Sunlight, temperature, slow-moving waters and
nutrients from fertilizer runoff.
"While there is some uncertainty in their role in red tide," said
Hudnell, "there is no controversy about the role of nutrients in
cyanobacteria blooms."
At a glance
What: Blooms of blue-green algae, called cyanobacteria. Does not include
"red tide," which is caused by a different organism.
Problems: Releases toxins that are poisonous to humans, animals and
plants; also causes degradation of water quality, fish kills.
Conditions for intensive blooms: Warm, stagnant waters; sunlight,
nutrients
Control: Preventing nutrients from fertilizers, animal waste and sewage
treatment discharges from entering surface waters.
What's next: Local government ordinances controlling the chemical
composition and application of fertilizers. Newly created state task
force to recommend basic statewide rules.
To report blooms or illnesses: (888) 232-8635