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By Nancy Baron THE CELLS FROM HELL
From Saturday Night Online
http://www.saturdaynight.ca/Toxic algae has killed 400 sea lions off the coast of California and four people in Montreal. Researchers are only beginning to understand the problem. One thing's clear: it's only getting worse.
In late May, 1998, on the beaches around Monterey Bay, California, the sea lions began to come ashore. Dozens of the 250-pound animals dragged themselves out of the water, lumbering across the beach and into nearby parking lots and campsites. Some collapsed with seizures. Others sat on the sand, dazed and swaying back and forth. "There were so many of them," recalls Bill Larzelere, a volunteer with the Marine Mammal Center in Sausalito, which had been called on to corral the sea lions. "Normally we'd use nets to round them up, but they were so disoriented that we could just put our hands on them and guide them over to the carriers."
Sea lions were found up to a quarter of a mile from the water; some had staggered out onto the median on the highway; some waddled along the sidewalk; smaller ones crawled underneath parked cars. One comatose sea lion was found sprawled across a pile of groceries in the kitchen of a restaurant, and another had crawled onto a building's roof and collapsed.
And then there were the dead ones.
"We were discovering large numbers of dead animals on the jetties," says Larzelere. "We found one small critter trying to suckle on a dead mother. It was an emotional time." Over the next two months, hundreds of sea lions washed up on the shores of local beaches. Eventually, over 400 dead sea lions were collected by an army of local volunteers that ultimately grew to eighty people.
When volunteers found an animal alive, they'd take it to the Marine Mammal Center. At first, researchers there were flummoxed. The sea lions seemed to be in good shape, except that they were completely unresponsive, dazed, and prone to sudden, violent seizures. Of the seventy sick sea lions brought to the centre, only twenty-two survived. After performing necropsies on the others, the researchers began to formulate a theory about what had caused the deaths. In analyzing the contents of the sea lions' stomachs, the researchers found traces of domoic acid; or, more specifically, remnants of anchovies that had ingested domoic acid - a toxin found in algal blooms, the proliferations of algae that occur every spring in coastal waters.
Domoic acid was familiar to researchers in Monterey Bay. Six years earlier, in 1992, pelicans and cormorants in the area had started falling from the sky, inexplicably. A vet at California Wildlife, a state preservation agency, enlisted a Canadian scientist, Jeff Wright, to help investigate the birds' deaths. At the time, Wright was the senior researcher at the Marine Bioactives Program with the National Research Council in Halifax, and an expert on toxic algae of the type often discovered in algal blooms. The vet sent Wright a number of samples taken from the dead birds' stomachs; Wright confirmed that the birds were victims of a toxic alga they'd ingested in tainted anchovies and sardines. The algae were called Pseudo-nitzschia and the toxin was domoic acid - the same toxin later found in the sea lions' stomachs.
We owe a lot to algae. Algal blooms are not only natural, they're essential. Fuelled by lengthening days, rising water temperatures, and nutrients churned up from the sea bottom, algal blooms kick-start and feed the entire marine food chain - including us.
Coastal waters turn red, green, or brown with the concentration of various algae, before the blooms are devoured by a bestiary of marine life - from the microscopic, single-celled zooplankton to a host of shellfish, including clams, mussels, oysters, and scallops.
But some blooms are, at least from our perspective, a good thing gone very bad. While blooms have always occurred, the incidence of toxic blooms - those in which at least some of the algae present is toxic - appears to be on the increase. In the last three years, countries from Hong Kong to the Philippines to Scotland have been forced to close down coastal fisheries due to toxic algae, and every major coastline in the world has now reported incidents of toxic blooms.
The commonest threat to shellfish-eating humans is Paralytic Shellfish Poisoning, or PSP, which strikes when we eat clams, mussels, or other shellfish that have ingested algae laden with a family of poisons called saxitoxins. Saxitoxins act like corks, blocking the movement of sodium through the nerves and thereby deactivating them. The result is paralysis - only your heart, which runs on a separate system, and your brain remain functional. Eventually you suffocate and die. There is no known antidote for Paralytic Shellfish Poisoning.
Some of the highest recorded levels of PSP toxins in the world have been found in British Columbia; for example, in a sample tested in B.C. in 1998, psp toxin levels had reached 31,000 micrograms for every 100 grams of shellfish. (The legal limit is 80 micrograms of toxin per 100 grams.) The 1998 reading marked B.C. as the second-most toxic coastline in the world, behind only Tierra del Fuego in Chile. At these levels of toxicity, a quarter-pound of mussel meat could easily kill sixteen people.
Scientists have long been familiar with PSP, which is why commercial mussels are regularly screened. But the toxins that cause PSP are only one kind of dangerous algae that have been uncovered. Researchers are continually learning about various strains of toxic algae and have come across some so frightening in their effects that they've been dubbed "cells from hell."
In January, 2000, the science journal Nature ran an article examining the sea-lion deaths in Monterey Bay. The article, whose lead author, Chris Scholin, is the head researcher at the Monterey Bay Aquarium Research Insitute, argued that because the sea lions were poisoned by domoic acid in anchovies, not shellfish, "monitoring of mussel toxicity alone does not necessarily provide adequate warning of [domoic acid] entering the food web at levels sufficient to harm marine wildlife and perhaps humans."
In other words, the testing systems we have in place can't guarantee our safety. While Jeff Wright and other leading algal experts dispute the article's conclusion, everyone agrees that even the most scrupulous tests can't always keep up with toxic changes in the oceans. It's a fact that Wright knows from personal experience. He'd also encountered the domoic-acid toxin during a health crisis in Montreal. In that incident, the domoic acid didn't kill pelicans or sea lions; it killed people.
In December, 1987, Jeff Wright was lying in bed one morning at his home in Halifax listening to CBC Radio, when a report about a mysterious illness sweeping Montreal made him freeze. "Two or three people came to the Montreal General Hospital one night with the same symptoms," recalls Wright, in his soft Scottish brogue. "The first one who came in was an old man in his eighties who'd had some kind of a stroke-like seizure. It was his birthday, I believe, a big family outing, and he was the star of the show. He'd had a huge plate of mussels. When the second person came in with the same symptoms - full credit to the hospital - alarm bells started to go off."
Over the next couple of days, 115 people reported ill to hospitals, mostly in the Montreal area. All had eaten mussels that were eventually traced to a commercial site in PEI. At the time, Wright's job at the Marine Bioactives Program was to examine marine organisms as sources of new leads for the pharmaceutical industry. Several days after he first heard the news report, Wright was contacted by Health Canada and the Department of Fisheries and Oceans and enlisted, along with his team of researchers, to help isolate the toxin in the mussels.
The most confounding aspect of the illnesses was the fact that the mussels eaten by the victims had been tested for PSP-causing toxins. "As the days went by, it was obvious that this wasn't PSP or any of the other standard toxins," says Wright.
The day the first patient died, "things hit crescendo," says Wright. "It put enormous pressure on Health Canada, the Department of Fisheries, and now our group, to find out what the toxin was."
The scientists at Health Canada knew that mice, when injected with an extract of a compound from the tainted mussels, died in a very characteristic, very peculiar way. They'd start by scratching behind their ears, and then, within fifteen minutes, they'd be dead. "The question was," says Wright, "what kills a mouse in that particular way?"
Wright and his team decided to break down the compound into isolated components, then see which one would still kill mice. Within 104 hours, working around the clock, Wright's team isolated the toxin. It was domoic acid.
Wright was familiar with domoic acid, but only from a seaweed in Japan where, traditionally, fishing cultures had used the toxin as a dewormer for children. The acid was administered as a weak dose in tea, which killed the worms but didn't harm the children.
Domoic acid, it seems, doesn't affect children's memories. Older adults, however, are a different story. Domoic acid blows out the part of the brain responsible for short-term memory. The acid prompts the cells in the hippocampus to fire continuously until they rupture. The damage is permanent. In extreme cases the patient's heart rate goes up and down erratically, breathing is laboured, and eventually the body just can't stand it. The brain seizes. Death follows within minutes.
Once Wright's team had isolated the toxin, the prime minister's Challenger jet was dispatched to Halifax to pick up Wright and deliver him to Ottawa. He arrived at around 10 p.m. and was immediately taken to Health Canada, where senior scientists from Health Canada and the Department of Fisheries were waiting. Wright reached into his briefcase and handed them a flask. The Health Canada scientists analyzed the flask's contents, and confirmed Wright's findings: domoic acid.
Wright's next problem was to figure out exactly where the domoic acid was coming from, so he headed back to his lab in Halifax to conduct more tests. "I opened up the stomach of a mussel," Wright recalls. "It was green, just loaded with something. I took it over to a young post-doc across the way. She drew these cigar-shaped cells. 'That's what it looks like,' she said. It turns out that we were looking at Pseudo-nitzschia, a type of algae. I kept that drawing for a long, long time." At the time, Wright remembers thinking, "You know, this could be a problem. Pseudo-nitzschia is found everywhere."
In nature, the struggle between predator and prey is never-ending. For an animal that can't run and hide, a toxic defence is a good alternative. It creates a memorably bad experience for predators - if the predator survives. Many marine organisms either concoct their own chemical cocktails or stockpile chemical weapons that they collect from other sources, such as toxic algae. Clams and mussels, for example, not only can withstand neurotoxins, they can use them in self-defence, transporting the ingested toxins to the part of their bodies most in need of protection - typically the pigmented tips of the shellfish's siphons, the part most vulnerable to nibbling by predators.
In response, some predators have developed toxin detectors. Young gulls, for example, have an automatic gag response. If they eat a clam tainted with PSP, they immediately regurgitate it. Given a mixture of toxic and non-toxic clams, sea otters taste them carefully and eat only the non-toxic ones. Somehow, they know. Humans, however, have no such defences.
Early accounts of coastal Indian tribes describe deaths from eating shellfish, and detail the use of toxic shellfish as a poison in tribal warfare. The first recorded incident of PSP was in 1793, when a member of Captain George Vancouver's crew died while mapping the mid-coast of B.C. A party went ashore and decided to cook up a breakfast of mussels. Vancouver wrote in his diary, "Soon after they quitted the cove several crew who had eaten of the mussels were seized with a numbness about their faces and extremities. Their whole bodies were very shortly affected in the same manner, attended with sickness and giddiness."
Although the others recovered, one crew member named John Carter did not. "He fell down and nevermore got up . . . his lips turned black and his face and neck were much swelled." As a result, wrote Vancouver, "to this bay I gave the name of Carter's Bay after this poor unfortunate fellow; and to distinguish the fatal spot where the mussels were eaten, I have called it Poison Cove and the branch leading to it Mussel Canal."
Shellfish have been monitored for PSP on Canada's west coast since 1940, when an outbreak on Vancouver Island killed three people. Monitoring began at the mouth of the Bay of Fundy four years earlier, after several people fell ill after eating shellfish. In 1982, testing was expanded to Newfoundland after a similar scare.
Tracking the country's coastal waters can be a logistical nightmare; B.C. alone has 26,000 kilometres of shoreline. In both the east and the west, the Canadian Food Inspection Agency (CFIA) works with fish farmers to monitor the coasts, focusing on the areas where there is commercial shellfish harvesting.
Testing for toxins is a finicky business. It requires a laboratory, several mice, and five to six hours. In B.C.'s southern waters, mesh sacks of mussels are dropped into the waters in seventy predetermined sites. Every week from May to October, and every second week the rest of the year, employees from the mussel fisheries collect a few mussels from each sack and send them by float plane to the CFIA lab in Burnaby, B.C. There, technicians make an extract from the shellfish, inject it into lab mice, and watch to see if they die.
"In B.C. we run three thousand three hundred to three thousand five hundred tests a year," says Klaus Schallié, a shellfish specialist for the CFIA. The agency performs about 6,000 tests for East Coast fisheries, bringing the national number of tests to roughly 10,000 a year. That represents about 30,000 mice. Researchers have long tried to develop a chemical test along the lines of do-it-yourself pregnancy kits that could determine shellfish toxicity in the field, but so far, they haven't come up with one.
Mussels are like the canary in the coal mine - because the mussels pick up the toxins quickly, they are an ideal early-warning system. But it also makes them risky to eat. Butter clams are even worse, because they can hold toxins for over a year.
It is almost impossible to monitor the outer coasts effectively, so the Department of Fisheries and Oceans typically enforces blanket closures in the north and on much of western Vancouver Island. Sometimes, harvesters become impatient for these areas to be reopened, so they resume collecting shellfish from areas that haven't been tested.
What's worse is that the demand for shellfish now exceeds the supply that can be legally harvested. Until the early nineties, cultured-shellfish harvesting was little more than a cottage industry; by 1997, the industry was selling $27.2 million worth of product each year, thanks mainly to the increased international demand for mussels.
This has created a hot market for poachers, who smuggle clams from closed areas into batches of legally harvested clams that have already been tested and cleared. These untested clams then make their way to restaurants and dinner plates. Poachers, of course, have no idea whether the mussels are toxic or not.
In 1999, police officers in Victoria, B.C., raided two downtown restaurants, seizing illegally harvested shellfish destined for diners. That same year, the owners of a pub in Sidney, B.C., were convicted of buying and selling improperly processed shellfish - charges laid following the hospitalization of a man who'd been poisoned by shellfish he'd eaten at the pub.
In order to combat the rising poaching problem, the Department of Fisheries and Oceans has dedicated its Special Investigations Unit, a squad formed in 1986, to tracking and arresting shellfish poachers on both coasts. The squad in Nanaimo, B.C., headed by fisheries officer Bryan Jubinville, comes complete with a clam-sniffing German shepherd named Dart; a useful addition, considering that patrolling B.C.'s coastal beaches can be a logistical nightmare.
"I wish people realized the severity of the stuff they are dealing with," says Jubinville. "PSP has no known antidote. And as much as we try to control it and make sure the product coming into the system is clean, there is illegal harvesting going on. There's legitimate harvesters and there's illegitimate harvesters. Any imaginable way that you can think of to beat the system, they'll try it. November through March is the busiest time for poachers because the night tides are low and it's particularly nice for those guys digging illegally because they can work with minimal lights. If we show up, they just hide."
That's where Dart, the patrol dog, comes in. Dart's highly refined nose is trained to find hidden caches of shellfish and to track the poachers who typically run and hide in the bushes at the edge of the beach when detected. Jubinville recounts one close call: "A couple of years ago we had an individual who was illegally collecting the product here on the east side of Vancouver Island and shipping directly to Calgary. One time when this occurred, this fellow was poaching product during one of the highest readings of PSP that I have known in my career - we were getting PSP readings that were astronomical. So we sent a couple of officers to Calgary to try and intercept this guy. We were fortunate that we got him in time."
Jubinville urges consumers to ask restaurants and shellfish suppliers about the reliability of their sources. He's concerned that most people are oblivious to the potential danger. "The primary thing I want the public to be aware of is the devastating effects this stuff can have on you." As for himself, what Jubinville has seen has put him off shellfish. "I still eat clams at home," he says, "but I won't touch them in a restaurant."
As Klaus Schallié points out, there are many folkloric "rules" among West Coasters about how to detect toxins in shellfish. He cautions against all of them. "Don't believe the common expression that shellfish are safe to eat in months with the letter R in them - blooms can happen any time of the year." In 1999, for example, PSP outbreaks on the West Coast lingered well into October and November. And nibbling on a single clam to see if your lips tingle before chowing down on more - another commonly believed old wives' tale - is not just bad advice; it could spell disaster.
In April, 1992, Kerry Affleck of Kamloops, B.C., was on his annual fishing trip to Kingcombe Inlet on B.C.'s west coast. Taking advantage of a low tide, he and his friends paused from their fishing to dig butter clams. They cooked a batch, planning to eat them later, but Affleck began to chew on one and quickly spat it out.
He then wandered off to fetch some water for coffee. Within ten minutes his fingers and toes started tingling. Hurrying back to the camp, he asked his buddy Rick Cole, a certified industrial first-aid attendant, if he thought this could be shellfish poisoning. Cole called the Coast Guard on his boat radio for advice. Glancing back over his shoulder, Cole saw Affleck stagger and collapse. "How fast can we get a chopper?" Cole yelled.
By then, Rick's father, Ken, who had eaten a few clams, was vomiting violently. Affleck, meanwhile, lay with his eyes wide open, turning blue. He was completely paralyzed, except for his heart, which kept on beating. Rick Cole began doing mouth-to-mouth on his friend, praying meanwhile that his father wouldn't stop breathing as well. As two helicopters arrived to evacuate the men, Ken Cole entered the same locked-in state as Affleck.
No one thought to lower the men's eyelids as the helicopters landed, and the draft glazed their eyes with blowing sand. Inside one of the choppers, the paramedics connected Affleck to an automatic respirator. Affleck remembers their conversation. "I heard one of the attendants say, 'I wouldn't have given mouth-to-mouth to this guy.' I guess there was green slime coming out of my mouth."
The helicopters took the men to the Port McNeill hospital. "No one there knew too much about PSP poisoning," says Affleck. "As the doctors walked off, they said, 'Well, there's no more we can do for him. We'll have to send him on his way.'" They meant to Vancouver, but Affleck, who could hear everything they were saying, thought they were going to pull the plug on his breathing apparatus. His racing heart set off the monitor's alarm. "Hey," said one of the doctors. "There's something going on here."
Affleck was airlifted to Vancouver and rushed to Vancouver General. (Ken Cole, who was less seriously stricken, recovered at Port McNeill.) "In Vancouver, a group of doctors stood around me," recalls Affleck. "One of them said, 'Be careful what you say; there's always a chance he can hear us.'" For two days, he floated in and out of consciousness. When he finally surfaced, his mother was at his bedside praying for him. "I guess it worked," were Affleck's first words.
Max Taylor, a marine-biology professor from UBC, did the analysis on the clams that Kerry Affleck had eaten. "With a toxicity 10,000 times that of cyanide, all it took was less than half a clam," he says, with a note of admiration.
Seven years after Affleck's poisoning, Max Taylor sits in his office in the University of British Columbia's Department of Ocean Sciences. Above his head hangs a three-metre-long oceanographic map. Red lines criss-cross the seas tracing his many voyages in search of these strange phenomena, harmful algal blooms or HABs, as they are known among scientists. Black-and-white portraits taken by electron microscopy adorn Taylor's shelves. In his rogues' gallery, each picture features different species of toxin-producing algae called dinoflagellates.
"I'm probably the world's oldest continuously studying harmful-algal-bloom expert," Taylor says, with a touch of self-deprecating humour. "When I first got into the field, only two or three phenomena were recognized. Now there is a huge diversity." Having studied dinoflagellates for thirty-eight years, Taylor has seen his once obscure fascination gain worldwide attention. Countries are seeking out Canadian expertise on the subject. And as the president of the newly formed International Society for the Study of Harmful Algae (ISSHA), Taylor is now working with scientists from around the globe to try to understand the reasons for the increase in toxic blooms.
He recalls the first meeting of scientists to discuss toxic algae in the early seventies; there were only ten delegates from two countries. Last winter, he says, the ISSHA hosted an International Conference on Harmful Algae in Tasmania. This time 500 participants attended, representing forty-seven countries.
"What's scary is that the range of harmful effects has proliferated marvellously," says Taylor. These tiny toxin makers not only kill humans, marine mammals, and fish, but they can cause Alzheimer's-like memory loss, disorientation, nausea, immune failure, even personality changes. The increasingly unpredictable occurrence of toxic algae, combined with an increase in poaching, is creating a situation that scientists agree is only going to get worse, because one thing is for certain: we can expect more algal blooms and their toxic brews.
More than two-thirds of the world's population are coast-dwelling, and the nitrates and phosphates we're dumping into the ocean seem to be playing a role in triggering these toxic events. Pollution doesn't create blooms, but it can feed them. As Jeff Wright says, "Do we have new blooms? Probably not. These organisms have been around forever. But as we dump more nutrients and phosphates into the sea, we increase the extent of the blooms by giving them what they need to grow."
Max Taylor agrees. "I don't for a minute believe that these species are changing and becoming toxic," he says. "What's different is how we interact with the environment. We have more people living in coastal areas, which means more nutrients from our activities on land, from agriculture, and logging. Pollution can change the blooms and so can global climate change. If summer comes earlier, temperatures heat up, and you have more nutrients; that's a recipe for disaster."
The burgeoning business of aquaculture, or fish farming, is also a growing source of nutrients for harmful blooms. The fish in enclosed fish farms produce a huge amount of waste, which in turn feeds the blooms. Last year, an epidemic of toxic blooms spurred Scotland to ban scallop fishing from 8,000 square miles of coastal waters; the blooms were blamed on waste generated by salmon farms. According to the Suzuki Institute, fish farms off the coast of B.C. dump sewage equivalent to that generated by a city of 500,000 people into coastal coves every day.
This December, experts on toxic algae will gather at Woods Hole, Massachusetts, for a symposium sponsored by the U.S. National Office for Marine Biotoxins and Harmful Algae - the first of a series of biannual meetings now scheduled to allow scientists to explore the problem. Taylor himself believes that another outbreak of poisonings - a major, deadly outbreak - is only a matter of time.
For now, trying to understand toxic blooms is like skipping ahead and reading the last chapter of a book. We know the ending, but the events leading up to the climax - the factors and exact conditions that cause the toxicity - are still unclear. The basic biology of most of the harmful species remains a mystery.
The research money to do the work also eludes researchers, even world experts like Max Taylor. "It takes a catastrophe to get funding. What we need out west is a really big disaster," says Taylor, adding ruefully, "If Affleck and his buddy had died, I'd have research money coming out of my ears."