Do not breathe: Dangerous, toxic gas found at Siam Square One

Have you smelled rotten eggs while wandering around Siam Square One?

That’s actually a highly toxic and flammable gas which has been sickening employees since the mall opened in June, according to health officials and the shop owners who’ve banded together to go public with their complaints to the media after they said the mall’s management ignored them.

They said five letters complaining of foul-smelling gas went ignored by mall management until health officials came last month and confirmed health-threatening quantities of hydrogen sulfide were found in the mall.

The mall has since acknowledged the problem but will remain open despite the confirmed, ongoing presence of highly toxic and dangerous fumes.

Sitprapat Rodpim, a shop owner at Siam Square One, filed a police report last week after the department store attempted to evict him because he closed his shop and displayed messages on the window glass warning shoppers of the toxic air.

“Warning: the hydrogen sulfide level in here varies from 10-83 ppm. The level is dangerous for living creatures!” shop owner Sitprapat Rodpim wrote on signs posted outside his closed shop to warn customers. Photo: Pantip

Another sign in English explained the shop had been closed due to the effect of the gas on the staff’s respiratory systems, which had made them sick.

Sitprapat also showed a medical note from his doctor proving he has been suffering from a sinus inflammation since five months ago, around the time the mall opened. Other shop owners reported illness in a Channel 3 news report.

“I don’t know how Chulalongkorn, which is an educational institute, allowed this to happen to the tenants and their customers,” Sitprapat said. “Why didn’t you close the mall? Why did you allow this to happen?”

The tenants said they have been smelling the gas since the opening of the shopping mall on June 5 and also believed the chemicals in the air caused rust damages to their metal products and even coins.

Damaged items posted on popular forum Pantip

The tenants said the toxic smell comes from the basement parking lot where the waste water system is located. They claimed the Department of Health inspected the building on Sept. 29 and found out the level of hydrogen sulfide in the basement reached an alarming level of 83 ppm. According to information about the gas, a level of 15 ppm is considered “high alarm.”

Typical concentration in clean air is about 0.0001-0.0002 ppm.

“It’s health-threatening,” one officer from the government who inspected the building said in a video distributed to the media. “The level should not exceed 10 ppm or even exist in the building at all.”

Although the scent can be observed clearly in the mall, it was unclear whether health officials took reading inside the mall’s common areas.

After the story went public, the mall management responded to the story Monday.

“We’d like to pay for the cost of damage to their products if they declare how many items were damaged,” said General Manager Ralintorn Lahori. “Or if they’d like to leave, we’d consider case by case because we haven’t really collected any rent since the opening.”

Despite the tenants’ complaints of the smell since the mall first opened, Ralintorn insisted the smell did not exist at first.

“There was no smell when the mall opened,” she said.

The smell is simply caused by a failed system to treat waste water, according to Chaiyaporn Polprasert, faculty head of Environmental Engineering at Chulalongkorn University.

“The system can be fixed by pumping out all the waste water out, which is not easy when we’re dealing with this amount of water,” Chaiyaporn said.

He added the original system must have been flawed.

“The gas indicates that the waste water was never really treated, and the system did not work,” he said.

A private company has been contracted to fix the issue, according to Siam Square One, and the smell should go away by next month.

“One month from now the smell should start to fade, and at the end of November there will not be any smell at all,” Ralintorn said.


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