The city’s public advocate is pushing the MTA to do more to ensure straphangers that the air at Penn Station is safe.

Letitia James said her office received several complaints about construction dust at the station near the A, C and E subways two weeks ago and it was concerning because of possible levels of toxicity.

“The air has been so dense, that observers had difficulty seeing the lights in the cramped ceilings due to floating airborne dust,” she wrote in a letter to the MTA.

James said there are air testing machines inside Penn, but they are far from the subway entrances. The MTA promptly responded to James’s inquiry and said the dust from those instances occurred during a demolition of a concrete staircase.

“This activity is now complete and no more such work remains; however, the one-time activity produced more dust than expected,” the agency wrote.

The MTA added that the contractor has retrained its workers to make sure they are keeping the dust out of the station. James, however, said she still would like more monitoring devices.

“As decisions about further major renovations of Penn Station continue, we must not forget the interim safety of our all who utilize and work at the station,” she wrote.