ORANGE (CBSLA.com) — A dozen social service staffers at an Orange County government building believe working inside the structure literally made them sick.

Forty-five new workers have been assigned to the building. Ironically, the new crew will supervise the Affordable Care Act, AKA Obamacare.

“We don’t have any concrete assurances that this building is safe for employees to come back into,” said union rep Jennifer Muir.

The union rep believes the building — located at 840 N. Eckhoff Street — could be a ticking time bomb.

The complex has been the subject of a bitter lawsuit.

Muir told KCAL9’s Tom Wait that she wonders why the federal government even wants to house workers in the building, formerly the home of an oil drilling company.

“We’ve had so many examples of women who have delivered children who have serious issues … people who have fallen ill with strange, auto-immune illnesses there is no explanation for, except for exposure to toxic chemicals,” Muir said.

A group of about 12 social services employees first went public with their concerns about the building about a year ago.

The group says their illnesses are directly related to exposure to toxic contamination. The union believes more testing should be done before anyone works in the building.

“I definitely think that a lot more testing needs to be done to assess the level and severity of the chemicals that still remain on this site,” said Muir.

The social services employees were ultimately moved out of the office space.

Orange County officials say the building is perfectly safe. They say a host of expert analysis shows soil samples contain toxic levels that fall within federal guidelines. Tests did not show any toxic chemicals in the air, reported Wait.

A spokesperson for county social services told Wait they have no vested interest in putting employees in an unsafe space. (He offered the spokesperson a chance to go on camera and the request was declined.)