By Michael Kahn
LONDON (Reuters) - Bad air could cause major problems forOlympic athletes who will have to deal with Beijing's pollutionand strict anti-doping regulations surrounding asthmamedication in August.
Olympic teams across the world are rushing to screen theirathletes to determine who has exercise-induced asthma, whichcan be triggered by smog and hurt performance. Many competitorsdo not even know they have the condition.
"What we are trying to do is diagnose who has asthma andget them on the right medication," said John Woodside, aphysiologist with the English Institute of Sport which iscoordinating the testing of Olympic athletes.
"There has been a special interest in these Olympicsbecause of the pollution factor."
Beijing is one of the most polluted cities in the world anddespite a 120-billion-yuan (8.8 billion pound) clean-up overthe last decade air quality remains a big concern.
Officials have pledged to cut the number of cars on theroad during the August 8-24 Games but some athletes are stillworried, including twice Olympic champion Haile Gebrselassie,an asthma sufferer who feared running the marathon would damagehis health.
The Ethiopian has pulled out of the Olympic marathon,though he hopes to run in the 10,000 metres in Beijing.
Experts believe there is good reason to worry. Tak Lee, anallergy and respiratory medicine researcher at King's CollegeLondon, said bad air combined with exercise could trigger adebilitating asthma attack.
The condition occurs when people inhale particles from theair during exercise, inflaming the lungs and making it harderto breathe. Some can run through it while others may get wheezyand have to stop.
VEHICLE EMISSIONS
The problem in Beijing is that all the vehicle emissions,construction sites and factories pumping pollutants into theair when combined with hot, sticky conditions might make ittough for athletes to catch their breath, he said.
"It is a concern," Lee said in a telephone interview. "Anattack of exercise-induced asthma can be quite severe."
Karen Holzer, part of the Australian team's medical staff,said the Australian Olympic Committee had increased asthmatesting for these Games.
She estimates exercise-induced asthma could affect anathlete's performance by up to 30 percent, underscoring theneed to identify and treat people with the condition.
"If they get a moderate increase in the asthma, it may meanthey have to pull out of the event," she said.
Once doctors diagnosed an athlete with exercise-inducedasthma, getting the waiver for using medication from theInternational Olympic Committee (IOC) was prettystraightforward, said Woodside.
The problem, however, is that some standard treatmentsbreak anti-doping regulations, requiring athletes to thinkabout more than just their training. Many sporting governingbodies have reminded athletes to make sure they know the rules.
Athletes need to ensure they have a valid therapeutic useexemption form so they can take medication.
BANNED LIST
So-called beta-2 agonists are banned as asthma medicationunless athletes have a therapeutic use exemption allowing themto take formoterol, salbutamol, salmeterol and terbutaline wheninhaled, according to the World Anti-Doping Agency (WADA).
These treatments work by copying certain effects ofnaturally-produced chemicals -- adrenaline and noradrenaline --to open up the airways so that more air reaches the lungs.
"Because some of the medication is on the banned substancelist the IOC must be sure that only asthmatic athletes areusing asthma medication," said Ken Van Someren, leadphysiologist at the English Institute of Sport.
"Although it should be stressed that therapeutic doses ofasthma medication will not have any performance-enhancingeffect."
The test involves measuring lung function before exerciseand then either after 10 minutes of hard exercise or 10 minutesafter an athlete takes asthma medication.
A drop of 10 percent or more in lung function wasconsidered a positive test and a signal the athlete needed tosee a doctor to get on medication, he said.
At the Los Angeles Olympics in 1984, 1.7 percent of allathletes who competed sought and were granted exemptions to useasthma medication, according to Joseph Cummiskey, a respiratoryphysician and member of the IOC.
This figure has steadily risen since then and in the 2004Athens Games 7.4 percent of the athletes were given exemptions,though some were rejected, he said.
(Editing by Clare Fallon)