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poluição na china
2008-01-25
As the lead exercise physiologist for the United States Olympic Committee, Randy Wilber has been fielding one bizarre question after another from American athletes training for the Beijing Games. Should I run behind a bus and breathe in the exhaust? Should I train on the highway during rush hour? Is there any way to acclimate myself to pollution? Wilber answers those questions with a steadfast, "No."

"We have to be extremely careful and steer them in the right direction because the mind-set of the elite athlete is to do anything it takes to get that advantage," he said. "If they thought locking themselves in the garage with the car running would help them win a gold medal, I'm sure they would do it. Our job, obviously, is to prevent that."

Wilber, a 53-year-old scientist based here at the United States Olympic Training Center, has spent most of the past two years vying with his counterparts from other nations to devise smarter, safer ways for athletes to face Beijing's noxious air.

To protect the athletes, Wilber is encouraging them to train elsewhere and arrive in Beijing at the last possible moment. He is also testing possible Olympians to see if they qualify for an International Olympic Committee exemption to use an asthma inhaler. And, in what may be a controversial recommendation, Wilber is urging all the athletes to wear specially designed masks over their noses and mouths from the minute they step foot in Beijing until they begin competing.

His multipronged strategy could give the United States team an advantage over teams from less-prepared countries. But the plan has a downside: it runs the risk of offending the host country, creating political tension.

Chinese officials say the air in Beijing, one of the most polluted cities in the world, will not be an issue when China's first Olympic Games start Aug. 8. They plan to limit vehicle use, close factories and do everything in their power to bring blue skies to Beijing. Jacques Rogge, the IOC president, said he was confident the air would be clean because Chinese officials "are not going to let down the world."

Rogge and Peter Ueberroth, the USOC chairman, recalled that pollution was a concern before the Summer Games in 1984 in Los Angeles and in 2004 in Athens, but that the air quality was not a problem when competition began. But with the Olympics less than seven months away, scientists are skeptical about the air quality for these Summer Games. Olympic teams around the world are preparing for the worst.

Pollution levels on a typical day in Beijing, some researchers say, are nearly five times above World Health Organization standards for safety. The marathon world-record holder Haile Gebrselassie, who has allergies, and the world's No. 1 women's tennis player, Justine Henin, who has asthma, have expressed reservations about competing in the Olympics for fear that pollution will exacerbate their breathing problems.

Some athletes who competed in Olympic test events last year complained that the foul air made it difficult to breathe and caused upper-respiratory infections and nausea. Colby Pearce, 35, an Olympic hopeful in track cycling from Boulder, Colorado, said he saw smog floating inside the velodrome in Beijing. His throat became scratchy and he developed bronchitis, he said, because of air pollution.

"When you are coughing up black mucus, you have to stop for a second and say: 'O.K., I get it. This is a really, really bad problem we're looking at,' " he said. The United States boxing team, while competing in China last month, ran in the hotel hallways instead of on the streets because the air was "disgusting," said Joe Smith, the team manager.

To combat the problem of air quality, Wilber and his counterparts from countries with sufficient money have been in silent, clandestine competition, each trying to devise a better plan. Jon Kolb, an environmental physiologist with the Canadian Olympic Committee, bristled when asked about Canada's plan, saying, "We would prefer to keep our strategies to ourselves." He did say, however, that Canadian athletes would not wear masks.

If Beijing is still badly polluted in August, the athletes most affected will be marathoners, triathletes and cyclists — endurance athletes who will compete outdoors for hours. Rogge has announced a backup plan for those sports. If the pollution level on competition days poses a danger to athletes, those events will be rescheduled.

The Body's Reaction
The body's reaction to pollution exposure is immediate, said George Thurston, a professor of environmental medicine at NYU School of Medicine. "Your body says, 'This air is bad; breathe less of it,' and that's a defensive mechanism," Thurston said. "For athletes, that means they will go into oxygen debt sooner and will start cramping up. At an event like the Olympics, that could be disastrous."

Pollution can also provoke allergic reactions, Thurston said, or set off an asthma attack. The risk of a heart attack rises on high-pollution days, he said. He worries most about ozone and particulate matter, two of five major pollutants — carbon monoxide, sulfur dioxide and nitrogen dioxide are the others — that could affect an athlete's performance. Vehicle emissions, coal-fueled factories and construction sites in and around Beijing generate the high level of air pollution.

"Ozone directly affects the lungs, and at high-enough levels, it would cause fluid to come into the lungs," Thurston said. "Particulate matter is actually breathed in, and the particles deposit on the lungs and can actually pass through the lungs and into the bloodstream. Both can cause acute reactions in people exposed to them."

Recently, Wilber has become an expert on those pollutants. Since coming to the USOC 15 years ago as a doctoral candidate at Florida State University, Wilber has helped athletes adapt to different environments: high altitudes, extreme cold, time-zone changes and, in the case of Beijing, high heat and humidity. In March 2006, his focus turned to the pollution in China.

Since then, he has traveled to Beijing three times to measure the pollution at each Olympic site. Along the way, he has bumped into some of his colleagues, all stealthily measuring the same air. He said none of them wanted to rely on the statistics provided by Chinese officials.

Wilber said his numbers were disturbingly high, with levels of certain pollutants "significantly higher" than they were at the 2004 Athens Games and at the 1984 Los Angeles Games. So Wilber scouted for possible alternate training sites in South Korea, Singapore, Japan and Malaysia for use in the days before the Beijing Games. The triathlon team will train in South Korea, and the canoe and kayak athletes will go to Japan.

"We've got to take a lot of precautions to keep our athletes away from the Olympic hoopla and out of the pollution before their event," said Chris Hipgrave, the Olympic high performance director at USA Canoe/Kayak.

Inhalers May Be Popular
The canoe/kayak athletes participated in Wilber's testing for exercise-induced asthma to see who may need an inhaler at the Olympics. The inhalers, which would help breathing by opening the airways, contain beta-2 agonists, a category of drug banned by the World Anti-Doping Agency. The IOC would then review the documentation of the athletes who hope to use the inhalers. Wilber said that one-fourth of United States Olympic athletes since 1994 had tested positive for exercise-induced asthma.

"It's pretty rare to have a full-blown asthma attack because of pollution, but it will affect an athlete's performance, and our testing shows that," Wilber said. "You're not going to drop dead, but your oxygen transport is definitely being compromised. It could mean the difference between a gold medal and finishing in the back of the pack."

Tim Hornsby, an Olympic hopeful in sprint kayak who has exercise-induced asthma, said having an inhaler would be crucial for those with breathing problems. "It's frightening to feel like you can't breathe," he said.

Wilber's USOC laboratory here helped design a mask featuring an activated carbon filtration system. He is secretive about the details, hesitant to show it or to have it photographed.

Roughly 750 to 1,000 masks, which cost about $20 to $25 each, will be part of the Olympic gear given to athletes. The masks filter 85 percent to 100 percent of the main pollutants, Wilber said, compared with paper masks, which filter 25 percent to 45 percent.

At the 2006 world junior track and field championships in Beijing, Wilber tested an early version of the mask, but it impeded breathing. After redesigns that Wilber would not describe, the new mask can be worn during training and competition.

The IOC spokeswoman Sandrine Tonge said the international federation for each sport made the rules on what athletes can and can't wear in competition. So it is conceivable that some athletes will wear masks during their Olympic events, but Wilber said no Americans would do so.

"I think it would be a huge political issue and an embarrassment to the Chinese people and to the IOC if American athletes wore masks in the event itself," Wilber said. "If that image was beamed around the world on TV, it would cause nothing but problems." He added, "It's much more important to guard against the pollution beforehand and go to the line with clean lungs."

In an effort to do that, United States triathletes wore masks in China last September, but removed them before competing. They stepped off the bus looking like a group of incredibly fit surgeons or, as one triathlete put it, a gathering of Darth Vaders. No other teams were wearing masks. Some opponents snickered.

"You do look kind of silly wearing it," said Jarrod Shoemaker, 25, of Sudbury, Massachusetts, who had competed in Beijing twice before. "But I wore it before the race this time, and I didn't feel burning in my throat afterward. I could still taste the grit on my teeth, but I could actually talk and breathe. That wasn't the case in other years. "For now, it looks like we're the ones with a huge advantage. We want to keep it that way."

(By Juliet Macur, International Herald Tribune, 24/01/2008)


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