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Dark tides and ill winds
ALL Susan Leydon has to do is stick her head outside and take a deep breath of sea air. She can tell if her 10-year-old son is about to get sick. If she coughs or feels a tickle in the back of her throat, she lays down the law: “No playing on the beach. No, not even in the yard. Come back inside. Now.”
The Leydons thought they found paradise a decade ago when they moved from Massachusetts to this narrow barrier island — called Little Gasparilla Island in Florida, which is reachable only by boat. There are no paved roads there but balmy air that feels like velvet on the skin.
Now, they fear that the sea has turned on them. The dread takes hold whenever purplish-red algae stain the crystal waters of Florida’s Gulf Coast. The blooms send waves of stinking dead fish ashore and insult every nostril on the island with something worse.
The algae produce an arsenal of toxins carried ashore by the sea breeze. “I have to pull my shirt up and over my mouth or I’ll be coughing and hacking,” said Leydon, 42, a trim, energetic mother of three who walks the beach every morning.
Her husband, Richard, a 46-year-old building contractor, said the wind off the gulf can make him feel like he’s spent too much time in an over-chlorinated pool. His chest tightens and he grows short of breath. His throat feels scratchy, his eyes burn, and his head throbs.
Their symptoms are mild compared with those of their son, also named Richard. He suffers from asthma and recurring sinus infections. When the toxic breeze blows, he keeps himself — and his parents — up all night, coughing until he vomits.
If the airborne assault goes on for more than a few days, it becomes a community-wide affliction. At homeowners’ meetings, many people wear face masks.
On weekends, the Leydons escape inland. They drive three hours to Orlando so their son can play outside without getting sick. They go to a Walt Disney World resort with water slides, machine-generated currents and an imported white sand beach.
“It’s a shame to leave this beautiful place and go to a water park,” Richard Leydon said. “But we don’t have much choice. We have to get away from it.”
Harmful algae blooms have occurred for ages. Some scientists theorise that a toxic bloom inspired the biblical passage in Exodus: “… (A)ll the water in the Nile turned into blood. And the fish in the Nile died, and the Nile stank, so that the Egyptians could not drink water from the Nile. There was blood throughout all the land of Egypt.”
What was once a freak of nature has become commonplace. These outbreaks, often called red tides, are occurring more often worldwide, showing up in new places, lasting longer and intensifying.
They are distress signals from an unhealthy ocean. Overfishing, destruction of wetlands, industrial pollution and climate change have made the seas inhospitable for fish and more advanced forms of life and freed the lowliest — algae and bacteria — to flourish.
A scientific consensus is emerging that commercial agriculture and coastal development, in particular, promote the spread of harmful algae. They generate runoff rich in nitrogen, phosphorous and other nutrients that sustain these microscopic aquatic plants. In essence, researchers say, modern society is force-feeding the oceans with the basic ingredients of Miracle-Gro.
Yet there is debate among Florida scientists over the precise causes of local outbreaks. Red tides date back at least 150 years, before the state became one of the nation’s most populous. Some scientists say their increased intensity is part of a natural cycle.
People who have spent many years on Little Gasparilla Island and in other Florida Gulf Coast communities say red tides used to show up once in a decade. Now, they occur almost every year and persist for months.
Red tide announced its arrival this summer by dumping dead tarpon and goliath grouper on the beaches. Soon after, coastal residents were coughing and sneezing.
The previous bloom, which ended in mid-February, peppered Florida’s western coast with its fiery breath for 13 months, stubbornly refusing to dissipate despite three hurricanes. The culprit is a micro-organism known as Karenia brevis. Each Karenia cell is a poison factory pumping out toxins collectively known as brevetoxin.
During red tides, they can be absorbed into the food chain by scallops, oysters and other popular seafood and can cause neurotoxic shellfish poisoning. The effects range from gastrointestinal illness to seizures, loss of muscle control and unconsciousness.
Brevetoxin also gets into the air. It collects on the surface of bubbles and concentrates in sea foam and on dead fish. When the bubbles burst, brevetoxin is flung into the air and carried by the wind.
If inhaled, most particles lodge in the nose and throat, but some are drawn deep into the lungs. People don’t have to set foot in the ocean or even on the beach to experience a red tide. It comes to them.
The Leydons thought they found paradise a decade ago when they moved from Massachusetts to this narrow barrier island — called Little Gasparilla Island in Florida, which is reachable only by boat. There are no paved roads there but balmy air that feels like velvet on the skin.
Most of those affected feel as if they have a cold or an allergy. But researchers reported last year that red tides coincided with outbreaks of severe respiratory ailments. They compared emergency admissions at Sarasota Memorial Hospital during three months of red tide with the same period a year later, when there was no toxic algae.
During the red tide, admissions for pneumonia, bronchitis, asthma, sinus infections and similar afflictions rose 54 per cent. No such increase was reported inland.
“You can tell when it’s a bad red tide,” said Dr Brian Garby, the hospital’s chief of emergency medicine. “The waiting room is filled with people coughing and they don’t know why.” Most alarming was a 19 per cent increase in cases of pneumonia, a leading cause of death among the elderly.
Brevetoxin doesn’t cause those maladies directly. Instead, researchers believe, it makes people vulnerable by inflaming their sinuses and suppressing their immune systems, allowing bacteria and viruses to flourish.
Boxy air filters stationed around Sarasota have detected the wind-borne neurotoxin three miles from the coast, said Barbara Kirkpatrick, a researcher at Mote Marine Laboratory, a private research institute in the city. “The public health message has been, ‘If you leave the beach, you’ll be OK.’
“Now we know better. People who are window shopping or eating in outdoor restaurants are still being exposed to the toxins.”
Hundreds of visitors from the Midwest and New England have posted questions and complaints on websites, seeking to learn why, after a short beach vacation on the west coast of Florida, they suffered weeks of coughing, bronchial infections, dizziness, lethargy and other symptoms.
Researchers are hearing a growing number of complaints about neurological symptoms. Ruth DeLynn, a 79-year-old retired biologist and volunteer curator at Mote Marine Laboratory, was hospitalised for five days last year with respiratory distress during a particularly virulent red tide.
DeLynn also experienced numbness and a burning sensation in her legs that made it difficult to walk. She and her doctor believe the toxin triggered a resurgence of peripheral neuropathy that had been dormant for 15 years.
“If this is going to continue this way,” said DeLynn, who lives on a barrier island near Sarasota, “I’m thinking of moving inland.”
Neurological symptoms usually flare only with high levels of exposure, said Dr Lora Fleming, a University of Miami epidemiologist and physician. “It’s all about dose.”
Fleming isn’t persuaded that people on the beach can inhale enough to suffer serious neurological effects, but she thinks surfers may be more vulnerable.
John Purdy, a former Manatee County lifeguard, was paddling his surfboard over a wave last fall when some sea foam lifted off the water and into his mouth just as he was gulping for air. “I felt like I inhaled a garbage bag,” said Purdy, 33, a former high school swimming champion.
“It locked up my lungs and throat like a paralysis.” The seconds ticked by. “I was thinking, ‘Is this the way it’s going to end?’ “ Eventually, he managed to sneak in a little air.
It was like sucking through a cocktail straw. He made his way to shore but didn’t feel much better until emergency medical technicians hooked him up to oxygen. “It was the closest thing I’ve had to a near-death experience,” he said.
Unlike surfers, marine mammals can’t seek refuge on land. Last year’s red tide took the lives of at least 88 manatees, some weighing more than a ton. Hundreds of these massive sea cows have succumbed during outbreaks in previous years.
Greg Bossart, a veterinarian and pathologist at Harbour Branch Oceanographic Institute in Fort Pierce, dissected the tissue of manatees and determined that many died from inhaling brevetoxin-laden air just above the ocean’s surface.
The result was a cascade of nerve and tissue damage that filled their lungs with blood. “The manatees are gassed to death,” Bossart said. “They die of toxic shock.”
Bossart considers the manatee a sentinel for human health, or, as he puts it: “Florida’s 2,000-pound canary. We’ve opened a Pandora’s box of health issues.” — Dawn/LAT-WP News Service (c) Los Angeles Times
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