Four days after L train riders began reporting noxious oil fumes on their commutes, the stench continues to linger, and multiple subway conductors told Gothamist on Thursday morning that the odor is no better than it was on Monday.

"It's making me uncomfortable," one conductor told a reporter at the Lorimer Street stop, adding that he has been riding trains on the L all week. "I'm not feeling too well. Yeah, nauseous, if you want to put it that way."

“I’m concerned about the smell," another conductor said. Asked if she was feeling nauseous or lightheaded, she nodded and pulled out of the station.

A third conductor, who like the others declined to provide his name, said it was his first time working on the L line, where he had been assigned because so many other workers had called in sick. "I smell it but what can you do?” he mused.

Asked if he was worried about the smell, an L train conductor who was finishing his shift at the Eighth Avenue stop replied, "Oh yes! We get drunk with the fumes!"

At least five MTA workers have been sickened by the fumes, according to the Transit Workers Union, and customers have fainted and vomited from the smell.

Pete Donohue, a TWU Local 100 spokesperson, said that on Thursday morning, "the union has pulled platform conductors off 3 stations—1st Ave., Bedford and Lorimer. They have been reassigned to stations outside the odor zone."

After the MTA shut down L train service between Brooklyn and Manhattan for several hours on Tuesday, they determined that the smell was caused by "non-flammable heating oil from an external source," but that source is still unknown. The state Department of Environmental Conservation said they found a minor water seep with sheens through the subway tunnel wall at Metropolitan and Graham Avenue. The DEC is continuing to investigate the seepages. Greenpoint and Williamsburg have seen numerous oil spills over the past century.

“I was at the Graham station today, and I want to reassure all New Yorkers that the air on the L train and in the stations is 100 percent safe," Pat Warren, the MTA's chief safety officer, said in a statement on Wednesday night. "We have removed almost all of the non-flammable heating oil near the Graham station and continue to vent the nearby stations as aggressively as possible."

Warren added, "We want to thank our customers for their patience while the odor dissipates and we thank the MTA employees for the difficult work they do every day to keeping the city moving.”

While the MTA has placed industrial fans at Graham Avenue, there were no fans at Lorimer Street on Thursday morning.

On Wednesday, L train riders talked with us about riding the train while breathing mysterious, sickening fumes:

Brooklyn Councilmember Stephen Levin, whose district includes the Bedford Avenue stop of the L, tweeted on Wednesday night that the MTA should replace L train service with shuttle buses until the issue is resolved.

[UPDATE 12:45 p.m.] In a statement, TWU Local 100 President Tony Utano called the current situation on the L train "completely unacceptable."

"The air still stinks and we are concerned about long-term exposure and the health of our members working 8-hour shifts along the line," Utano said. "We have pulled workers from some locations and if the situation is not abated over the weekend we will take further action to protect the safety of our members and that of the riding public."

Listen to Jake Offenhartz discuss the fumes with Jami Floyd on WNYC's All Things Considered:

This is a developing story, check back later for updates.