Tuesday, September 18, 2007

Goop 1, China 0

Environmental activist Zhang Zhengxiang points at toxic algae on China's Lake Dianchi

The goop that's swallowing the world

Across the globe, toxic algae outbreaks are getting bigger, nastier and more frequent. Can anything stop the rising tide of poisonous muck?

By Jonathan Adams
Newsweek International, September 24, 2007 (original draft)

Beside a lake outside Kunming, China, environmental activist Zhang Zhengxiang jabs his finger angrily over the water. The surface shimmers a bright, fluorescent green from the toxic algae that now clogs large swathes of the high-altitude, freshwater Lake Dianchi for most of the year.

The day-glo water may be pretty from a distance. But it's the tell-tale sign of a lake that's profoundly sick. Before the early 1980s, says Zhang, this was a swimming area, and shrimp from the lake was a prized delicacy at high-end restaurants in Shanghai and Beijing. Now, the lake's shrimp are inedible, and the toxins in the algae make swimming a decidedly unpleasant experience.

Zhang yanks up his trouser leg to show the rash left on his ankles from a recent wade into the once-pristine waters. "If you go in, your skin will turn red immediately," said a disgusted Zhang.

China's breakneck economic development has resulted in the world's fastest-growing toxic algae problem. But it's hardly alone.

Red tides of algae

Across the globe, scientists and officials are scrambling to contain a rising tide of poisonous green, brown and red goop. Monster algae blooms and toxic strains are laying waste to coastal fisheries, poisoning shellfish, sickening beachgoers, driving away tourists and fouling freshwater lakes and reservoirs -- some of which are critical sources of drinking water for nearby communities. Economic losses from toxic algae have been estimated at 830 million to 1.3 billion euros per year in Europe alone.

Pollution is the primary culprit. But now, scientists say a "perfect storm" of that and other causes -- overfishing, the transport of toxic algae species in the ballasts of ocean-going vessels, freak storms and global warming -- is raising the problem to unprecedented levels.

"We have more toxic algae species out there, more fisheries resources affected and higher economic costs," said Don Anderson, a top algae expert at the Woods Hole Oceanographic Institution in Massachusetts. "Globally, things are getting worse."

Growth in coastal algae blooms from 1970 to 2006

From Friend to Foe

Of course, most algae is harmless. In fact, it produces much of the oxygen necessary for animal life on earth, absorbs carbon dioxide, decomposes into critical fossil fuels, and is the base of marine food chains.

"If there's no algae, there's no ocean life," explained Wang Zong-ling, an algae expert at the First Institute of Oceanography in Qingdao, China.

Some algae is naturally toxic to humans and other animals, possibly to ward off predators, guess scientists, or else as a chemical fluke.

But rapid economic growth in advanced countries in the 20th century -- and now, in booming Asian economies like China's -- have increasingly turned algae from friend to foe.

Rising human exploitation of coastal areas has led to more run-ins with naturally occurring toxic algae. Meanwhile, pollutants have greatly increased the size and frequency of high-density "blooms" in oceans and lakes. In a reversal of algae's usual role, such blooms actually suck oxygen out of the water as they're dying, killing or driving away nearby aquatic life. And as such algae blooms increase in frequency, the amount of toxic blooms -- about a quarter of the total -- soars in proportion.

Fertilizer runoff from farms, factory waste, and untreated sewage are the key ingredients for many runaway algae blooms. Nutrients in such pollution fatten blooms to previously unseen sizes. Red algae feast on nitrogen, causing massive coastal "red tides", freshwater blue-green algae munch on phosphorous. Both types can also feed on nutrients from the atmosphere, for example in dirty rain.

Perhaps the most striking proof of the link between pollution and monster algae was the dramatic decline of such blooms' size and frequency in the northwest Black Sea in the early 1990s. That happened just after the former Soviet Union halted subsidies to the area, which greatly reduced fertilizer usage.

China: goop central

Today, the link between pollution and monster blooms is most apparent in China. Rogue algae is just one symptom of the environmental price China is paying for its roaring economy. Rapid growth has meant a surge in nitrogen and phosphorous pumped into the nation's waterways, which has fed both ocean and freshwater blooms.

So-called "red tides" off the Chinese coast have become larger and more frequent in recent years, particularly in the East China Sea off Shanghai. There were 22 red tides on the Chinese coast in 1998, according to government statistics. By 2005 there were 82 -- including 38 toxic blooms --covering more than 27,000 square kilometers and causing economic losses to the tune of $9 million.

"I wouldn't be surprised if more red tide events are reported along Chinese coasts in the near future," said Zhou Mingjiang, a red algae expert at the Institute of Oceanography in Qingdao. "The problem is getting worse."

Toxic blooms on China's freshwater lakes and reservoirs are even more worrisome, since they can impact critical tapwater supplies. This summer, the worst-ever such blooms were a media focus in China, as one lake or reservoir after another fell victim to poisonous goop. In May, a blue-green algae bloom on Lake Tai caused mass panic when it contaminated the water supply of 2 million residents of the city of Wuxi, in Jiangsu Province. Huge blooms were also reported on Lake Chao, further inland. And in late July, 100,000 residents in the northeast city of Changchun went waterless when a toxic bloom appeared on a key reservoir.

But the Ground Zero of China's toxic algae problem may be Lake Dianchi, in southwest Yunnan province. The situation's so bad that the nearby city of Kunming is now forced to gets its drinking water from upstream reservoirs instead of the lake. For at least five years running Dianchi's water has rated "5" or more on a key water quality index, meaning it's completely useless.

One reason: unlike with lakes further downstream in the Yangtze river system, officials can't divert river water into Lake Dianchi to help flush out toxic algae blooms. That's because it's too high -- nearly two kilometers above sea level – and fed by small mountain springs, or rivers that are themselves polluted. Nitrogen and phosphorous pours in from all sides and accumulates, turning the lake into the equivalent of a 200-square-kilometer clogged toilet bowl.

Lake Dianchi, outside Kunming, China

Other causes: overfishing and global transport

Such pollution isn't the only cause of monster blooms. In the Baltic Sea, the overfishing of cod has thrown the food chain out of whack in a way that leaves algae -- including the toxic kind -- the big winner. Fewer cod has meant more herring and less tiny critters called copepods, which are algae's natural predator.

Add plentiful nutrients from decades of fertilizer use and untreated runoff from countries surrounding the sea, and the result is goop gone wild: The largest-ever algae blooms were recorded in July 2005 and 2006, covering almost 150,000 square kilometers. (This year wasn't as bad due to heavy rains).

In Sweden, tourism has suffered, and swimming is a no-no in many areas because the toxins in the algae burn the skin. Unlucky dogs have slurped up algae-filled Baltic seawater containing hallucinogenic neurotoxins that give them the equivalent of a canine acid trip before killing them. And the blooms have become a massive eyesore on what was once an idyllic sea view.

"It's this huge brownish thing floating on the surface," said Edna Graneli, an algae expert at the Department of Marine Sciences at the University of Kalmar in Sweden. "If Jesus walked on water, it must have been on one of these blooms."

Algae blooms, Baltic Sea

Meanwhile, toxic algae is being shuttled around the globe by weird weather and ocean-going ships, whose numbers have soared along with globalization. The recent red tides off the northeast US coast, for example, are blamed primarily on a massive 1972 storm that introduced a foreign strain of algae to the region. This year for the third summer running, those tides led to a ban on shellfish harvesting, because mussels and clams mop up toxins in algae that can sicken and even kill humans if consumed in high enough concentrations.

And scientists suspect that a strain of toxic algae only recently seen in the Mediterranean may have hitched a ride on a ship from Brazil, where a genetically identical type has also been found. That toxic algae first grabbed headlines in July 2005 in Italy. Swimming was banned along a 15 kilometer stretch of the Italian Riviera near Genoa (including the elite, yacht-packed Portofino) after 200 people sought hospital treatment for nausea, diarrhea, stomach cramps, breathing difficulties, irritated eyes and vomiting. Such was the impact that local officials initially feared a bioterrorist attack.

What's most caught scientists attention is that this algae can spread toxins in airborne water droplets over large areas. Climate change may abetting the troublesome strain through warmer, more algae-friendly temperatures in the Mediterranean.

"We are facing a new kind of problem," said Naples-based algae expert Adriana Zingone. "But we're doing our best not to spread alarm about the situation."

Mission impossible

Battling toxic algae isn't easy -- and requires expensive and in many cases coordinated, multinational efforts. For low-density toxic algae like the one now plaguing Italy, there's very little that can be done. Strict new rules on the ballast discharge of ocean-vessels will hopefully reduce the further global spread of such species, and other "bioinvaders."

But where such strains have already set up shop, avoidance may be the only option. Experts cite the US state of Florida -- where red tides have long plagued Gulf of Mexico coastal waters -- as a model in creating monitoring and warning systems to keep humans out of harm's way during toxic algae attacks. And Japan has become adept at simply moving its aquaculture when it's under threat.

South Korea has successfully protected small aquaculture sites by dumping clay pellets in the sea; algae sticks to the pellets and then sinks to the ocean floor. But that technique is controversial in the west, where environmentalists worry about the unknown long-term effects. It's only feasible for small, targeted areas -- not for battling blooms like the Baltic's that spread over thousands of square kilometers, or for larger-area industries like Chile's salmon farms. And it deals with the effects of blooms, rather than their cause.

"Algae problems aren't something you can get rid of easily," said Ma Jun, an environmental activist at the Beijing-based Institute of Public and Environmental Affairs. "There's no silver bullet."

China's learning that the hard way. For its lakes -- and places with similar high-density blooms like the Baltic Sea -- the only real solution is to tackle the problem at its root. That means curbing the amount of nitrogen-and phosphorous rich pollutants that enter the water.

View of Lake Dianchi from Xishan

But at Lake Dianchi, the challenge of doing that is evident. Some $660 million has been spent on the problem in the last decade, with measures such as curbing industrial pollutants, building sewage treatment plants, intercepting polluted water and banning detergents containing phosphorous. But the situation remains dire. One reason, say environmentalists, is that the government hasn't been willing to crack down on fertilizer use.

"We've been using too much fertilizer in agriculture," said Liu Hongliang, a retired environmental engineering expert. "[Lake algae] will become more and more serious in the coming years."

By one estimate, 40% of pollutants that continue to pour into the lake come from agricultural runoff that continues unabated. The farms on the lake's eastern shore produce massive crops of roses and other popular flowers for markets in Asia and beyond. Farmers douse fields with fertilizer to increase yield.

One elderly couple wrapping bundles of flowers at a lakeside farm told NEWSWEEK that lakewater was pumped up the lake banks to irrigate the flower fields, and then drained -- untreated -- back into the lake. Bright green algae floated in the drainage ditches dug between fields lined with plastic hutches. Such farms provide livelihoods and critical growth for the local economy -- even as they dump noxious chemicals into the nearby lake.

No easy fix

Even countries that have successful curbed pollutants haven't solved their algae problems. With the most advanced water treatment plants on earth, Sweden is a model in this area. But it can't fight the Baltic's megablooms without help from neighboring countries whose water treatment is far less stringent. Japan spent massive amounts to successfully reduce high-density blooms on the inland Seto Sea, only to see lower-density toxic algae actually become more frequent.

And stopping the flow of new pollutants into waterways doesn't clean up the accumulated gunk of decades that's already fouled many lakes and coastal areas. Experts say removing such existing nutrients from lakes is possible but exorbitant -- and removing them from coastal waters may be impossible.

"How do you empty huge ecosystems of nutrients? There's no easy answer to what can be done," said Henrik Enevoldsen, coordinator a the IOC Science and Communication Centre on Harmful Algae in Copenhagen.

In many places, there's also little urgency in tackling the algae problem -- until it affects drinking supplies, as in China. Though its impact on marine species is at times dramatic, such species usually rebound nearby: Witness the rock lobsters periodically decimated by dying red tides that suck oxygen out of water off South Africa.

Shellfish poisoning due to toxic algae strains can be life-threatening, and contaminated drinking water is linked to liver and other cancers. Still, as a health problem, toxic algae pales next to greater global threats.

Its major impacts are economic and social. Developing countries like China are increasingly dependent on freshwater lakes and reservoirs to supply drinking water to swelling populations, and on coasts for food, tourism and livelihoods.

"If coastal zones are constantly impacted by massive blooms or toxic species, then we can't exploit these resources," said Enevoldsen. "That's very problematic."

Humans are turning critical waters to goop through unchecked economic activity. Unless that's curbed, more and more will suffer the toxic fate of China's Lake Dianchi.

With Wang Zhenru in Beijing

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