BEIJING -- Athletes competing in a marathon on Sunday showed less concerns for air pollution during the incoming Beijing Olympics rather than possible heat waves and humidity.

Competitors start Good Luck Beijing 2008 Marathon in front of the Tiananmen Square in Beijing April 20, 2008. The marathon ended at the National Stadium, also known as the "Bird's Nest". [Agencies]

The 42.195-kilometer race was held as a test event for marathoners to run on a newly designed Olympic course which meets historical cites and major business streets including China's top two universities and is different from that adopted in annual Beijing marathon event.

The temperature dropped to about 15 Celsius degrees after the start, much cooler than the last two days when a race walking challenge was held at nearly 28 degrees. It turned heavy raining one and a half hours later, breaking up mass martial art performance in the finish, the National Stadium, or "Bird's Nest".

"Although it is freezingly raining today, I would make more preparation for heat and humidity in August," silver medalist Zhou Chunxiu, expected as another Olympic hope for China's track and field besides hurdler Liu Xiang, said in all wet body covered by towel after race.

No information from the marathoners was available during the race because the organizers temporarily canceled live TV broadcast on Sunday morning, giving a reason that there was no remote pickup unit in a short notice.

Being repeatedly asked by foreign journalists for a comment on Beijing's air pollution, many athletes stood shivering when passing the mixed zone, leaving only "it is cold."

"The pollution yesterday was bad, but today it rains and does not really bother the competition," said Mara Rosalind Yamauchi who finished fifth.

"Air pollution will be a challenge for the Olympics and I hope the organizers could improve it," she said.

The British, who married a Japanese, said she will come to Beijing this summer and try her best in marathon, but also confirmed that she will do her training in Japan, Macao and Switzerland before August.

"The overall preparation is good, it is just a test event," Yamauchi said the course is "smooth" and the stadium is "fantastic", despite some details to be improved.

Mongolia's Serod Batochir, gold medalist in men's race, said he had not felt any pollution because of the rain, adding that hot and wet weather in August will be a more headachy problem for him.

Toilet was another issue in the marathon race started from Tiananmen Square at the heart of the capital as a symbolic venue to hold prominent ceremonies in China.

The British marathoner told she has not found any toilets at the start to some foreign journalists.

However, some Chinese journalists and volunteers who had not been to the marathon start insisted that there must be some toilets since Beijing has held many marathons.

"It is also possible that the British athlete did not ask the volunteers at the start or they failed to told her toilet's location," one of the volunteers working at a press conference room for the race, "it is unfair to say there is no toilet only for one athlete claimed she didn't find one."