For months, Staten Island residents and environmental officials have tried and failed to identify the source of a stench described as a revolting combo of rotten eggs and broccoli.

The malodorous mystery seems to be emanating from sewers on Merrill Avenue near Graham Avenue. The city’s Department of Environmental Protection has installed filters in manholes to reduce the stench and is continuing to investigate. But in the meantime, residents told Gothamist they are continuing to endure the foul smell, which has caused burning eyes, headaches and nausea.

Some people said they left their homes and stayed elsewhere during particularly pungent stretches.

“We would go like a week or two, not smelling it, and then all of a sudden, boom, you’re smelling it really bad,” said Deborah Phelps-Seda, a call center agent who works from her apartment on Merrill Avenue. “The month of February was torture for us, absolute torture.”

The Bull’s Head neighborhood has a long history of stinky smells. Fresh Kills Landfill, which closed in 2001, was only a couple miles to the south. For some residents, the new stench brought up old memories.

Workers flushed the sewers earlier this year following complaints about the stench. But residents say the smell still returns.

Courtesy of Deborah Phelps-Seda

“At one point, [the smell] was almost as if they opened the dump again,” said Rob Angelone, a retired FDNY officer who lives nearby. “I don’t know how the people who live on Merrill weren’t physically getting sick from it.”

During a recent visit to the neighborhood, residents had many theories on what the cause could be. But they didn’t think it was the landfill site, which is now a park three times the size of Central Park.

Many residents initially suspected a gas leak because of the rotten egg smell. But environmental officials ruled that out. Residents said city officials told them the odors were originating from sewer manholes on the street. Jerry Reilly pointed at a manhole in the middle of the street, directly in front of his house.

“That’s where it’s coming from. Right over there,” Reilly, a retired correction officer, said. “If you have your windows open, you’re gonna smell it.”

Reilly said the smell did not infiltrate his home. Phelps-Seda wasn’t so lucky. She said the odor overwhelmed her dining room and kitchen. She and her husband sealed doors to those rooms with plastic, seeking to quarantine the stench.

“Even though the smell was outside, the smell was so strong in my house,” Phelps-Seda said. “So when you open the windows, it helped air it out.”

She described the smell as “rotten eggs.”

“But then sometimes … because it’s from underneath my sink, it will smell like rotten broccoli,” Phelps-Seda said.

Deborah Phelps-Seda points at the plastic she and her husband have used to reduce the spread of the smell.

Rhiannon Rashidi / Gothamist

She said her heat bill doubled in February because she left the windows open to release the stink. She said she’d taken the family to hotels at least five times.

“We had to evacuate late at night because I didn’t want us breathing it in, especially with [my son] being sick with pneumonia,” Phelps-Seda said. “I’m like, ‘Here’s the Tylenol, get in the car, we gotta go.’”

Gothamist visited the intersection last week, and didn’t smell the stench. But every resident cautioned it could come back at any moment, and 311 data shows complaints about the stench since December.

Phelps-Sada’s upstairs neighbor Amity Nigro said she left her apartment at midnight on Jan. 24, unable to endure the stink. She was gone for two weeks straight.

“To just do one load of laundry, to stay there for an hour, it was like a massive headache and nausea,” Nigro said.

Environmental protection spokesperson Deja Stewart said the agency is on the case.

“Crews inspected and cleaned the sewers at Merrill and Graham avenues and found all infrastructure operating as intended. We also installed filtration devices in nearby sewer manholes to help reduce odors,” Stewart said. “DEP is conducting ongoing wastewater and air sampling, reviewing data collected at the site, and has been in contact with nearby businesses to gather additional information. Our investigation into the cause remains ongoing.”

Councilmember David Carr, who represents the area, urged the health department to join the investigation. He said he also alerted Mayor Zohran Mamdani’s office.

“We want to make sure that this ends because people are talking about putting up for sale signs,” Carr said. “People chose this neighborhood for a reason and we want them to stay and be safe, secure and happy in their homes.”