Between 150 and 200 Asian Games athletes have already been tested for doping, the Olympic Council of Asia said on Monday, with no positive results so far.

Speaking at an anti-doping press conference on the second full day of the Games in the Chinese city of Hangzhou, the OCA said dope-testing was "gaining momentum" at the event.

Mani Jegathesan, an adviser to the OCA anti-doping committee, warned that drug cheats would be rooted out.

Up to 200 athletes have been tested so far, he said, but any positive results will take several days to come through.

"Every athlete participating in these Games must understand that they could be picked at any time," Jegathesan warned.

"That is the best step to ensuring we have a clean event."

There are about 12,000 athletes at the 19th Asian Games, more competitors than the Olympics, and Jegathesan admitted it would be impossible to test them all.

Instead, they will prioritise, including picking out those who break world or Asian records.

Qin sets new Asian Games mark

Breaststroke world champion and title favourite Qin Haiyang smashed the Asian Games record to surge into the 100m final on Monday as China set about shoring up their dominance in the Hangzhou pool.

The Chinese star caused a major upset at the world championships in Fukuoka in July when he won gold in 57.69 ahead of a stacked field in the absence of British great Adam Peaty.

He went on to complete an unprecedented clean sweep of the breaststroke titles, an achievement he is aiming to match at his home Asiad as he builds towards next year's Paris Olympics.

Qin, the second-fastest ever over 100m after Peaty, was in a class of his own in the heats, touching in 58.35 to better the previous Games best set by Japan's Yasuhiro Koseki in 2018.

South Korea's Choi Dong-yeol came in second -- a gaping 1.55 seconds behind Qin.

Qin has already claimed a silver after finishing second to storming Olympic champion Wang Shun in the 200m medley on the opening night of action on Sunday.

Wang's 1:54.62 was not only a new Asian record but made him the third-fastest man in history behind only swimming great Michael Phelps his fellow American Ryan Lochte.

It was one of seven gold medals won by the hosts, who swept all the titles on day one when a raft of Asian records were set.

Siobhan Haughey cruised into the 200m final as she looks to win Hong Kong's first-ever Asian Games swimming gold.

Haughey did not compete at the 2018 Asiad due to a nagging foot injury, but has since become one of the top freestyle swimmers in the world.

After earning silver behind Australian star Ariarne Titmus at the Tokyo Olympics, she narrowly missed the medals at the July world championships.

But she reinforced her credentials with a silver in Fukuoka over 100m behind flying Australian Mollie O'Callaghan.

Haughey qualified fifth-fastest in 2:00.75, conserving energy while capable of swimming under 1.54. China's Li Bingjie (1:58.90) was best through the heats.

In other action, China's Xu Jiayu backed up his gold medal in the 100m backstroke by qualifying fastest over 50m in 24.99.

China's Wang Xueer led the field into the final of the women's 50m backstroke in 27.59, while South Korea's Ji Yuchan (21.84) was quickest in the men's 50m freestyle.

Chinese teenager Pan Zhanle also made the 50m freestyle final, a day after swimming a monster 46.97 to shred the Asian record and take 100m gold. In the process, he became only the fifth man ever to go under 47 seconds.

Meanwhile, China's Yu Yiting (2:14.02) was quickest in the women's 200m medley heats, backing up her bronze medal performance in Fukuoka.

India fires first world record

India claimed the first world record of the Hangzhou Asian Games on Monday as hosts China snapped up more gold medals and 15-year-old skateboarder Hinano Kusaki triumphed for Japan.

The Indian trio of Divyansh Panwar, Rudrankksh Patil and Aishwary Tomar blew away the field with a new world best 1,893.7 points to win the men's 10m air rifle team event on day two of the multi-sports extravaganza.

They beat the previous mark of 1,893.3 set by China last month in Baku.

In doing so they won India's first gold of a Games where the hosts have swept 28 of the 44 titles decided so far.

"In the 10m event they are both perfect athletes," Tomar said of his teammates. "Playing with them is huge, it's really good."

Another shooting world record fell to China's Sheng Lihao in the men's 10m air rifle with his 253.3 points surpassing teammate Yu Haonan's 252.8 from Rio four years ago.

"I had good luck in the final. I did quite well today, I was basically smooth," said Sheng.

Like India, Macau clinched its first gold in Hangzhou, with wushu athlete Li Yi winning the changquan title to become the first woman in history from the Chinese territory to earn an Asian Games gold.

"I'm really proud. This one completes the process so I feel really fortunate," said the 31-year-old.

"This maybe brings my 20 years as an athlete to a perfect end."

In other early action on day two, Kusaki dazzled in skateboarding to easily win the women's park final at Qiantang Roller Sports Centre.

"I am very happy with how everything went," said the teenager.