One of New Hampshire’s largest landlords, Brady Sullivan Properties, is under scrutiny from city, state and federal regulators for lead contamination in one of its buildings in Manchester.

Tenants contend their landlord and a contractor hired by Brady Sullivan are responsible for the lead dust that permeated their apartments, and 22 have filed a lawsuit.

It will be up to the courts to determine who’s at fault, but one thing is clear: Brady Sullivan has downplayed the health risk to its tenants in the weeks since the contamination happened.

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Brady Sullivan has made a name for itself converting old mills around New England into commercial and residential space. But since many of those mills spent decades as industrial sites, they often come with a host of environmental risks, requiring complex renovations.

"So a contractor will come in," says Beverly Drouin, a lead expert with the Department of Health and Human Services, "they’ll remove the lead, the asbestos, the pigeon guano, the PCBs, the mercury, whatever’s in that building – but that building is empty. Never in my professional career have I ever seen sandblasting activities in an occupied building."

That is, she had never seen sandblasting in an occupied building until May 12, when regulators shut down a construction site just below 98 Brady Sullivan apartments in a Manchester building called Mill West. Brady Sullivan markets Mill West as a luxury development, and rents range from $1,200 to $2,550 a month.

Within one day of regulators stepping in, here’s what was clear: Brady Sullivan’s contractor did not have the proper permits or training; toxic lead dust had piled up in at least one apartment; and tenants had complained clouds of dust poured through their windows and cracks in their floors.

Infographic: A timeline of lead concerns at Mill West

Yet two days later, Brady Sullivan sent an email to tenants stating the dust had been fully contained, and there was no evidence of a “risk of any health hazard.” Since then Brady Sullivan’s efforts to address the problem prompted regulators to crack down on the landlord, pushed a contractor to quit, and left many tenants angry, scared and confused.

The biggest known lead hazard in recent New England history

Kurt Milligan’s apartment was the first found to have dangerous levels of lead dust.

"They have a complete disregard for the health and safety of everyone in their building," Milligan says of his landlord.

Lead is a powerful neurotoxin, particularly for young children and developing fetuses. It can cause serious problems, including lowered IQs, hyperactivity and behavior and learning problems. Federal law cracked down on lead paint in 1978, but it is still a problem in many older buildings, especially when renovations create dust that settles in living spaces.

"I am happy to discuss any issues you may have but can tell you the constant threats to call city officials and code enforcers will not remedy anything for you. The vendors are doing everything by the book as allowed by their permits." Email from Scott Payrits of Brady Sullivan to Mill West tenant Cody Mattiello, May 8, 2015

When Milligan found out his apartment was full of lead dust, he and his fiancée, Barbara Bannon, moved out. She was pregnant.

"It’s a public health issue," says Bannon. "It’s not just our issue. And our physician overseeing the pregnancy also said that unless it’s considered completely lead free, that I should not be living in the building at those levels."

So how exactly did this happen? How did dust invade dozens of luxury apartments, creating the biggest known lead hazard in recent New England history?

It starts in late April, when a Brady Sullivan contractor began sandblasting lead paint off the walls of the lower two floors of Mill West. Brady Sullivan planned to convert that space into 210 more apartments.

Tenants upstairs and in an annex building complained about noise and dust, and Brady Sullivan assured them the contractor, Environmental Compliance Specialists Inc, had proper permits. But tenants organized themselves after some learned that, just last year, a storage company battled with Brady Sullivan over lead dust – in the same space now under construction under their feet.

Dozens of tenants hired Debbie Valente of Alchemy Lead Management to test their apartments. She took photos of window wells that she says were coated in lead dust.

"Well, it’s filthy," says Valente. "This picture shows you how filthy. I can scoop teaspoonfuls of debris out of the window wells."

On one windowsill on the fourth floor, Valente found lead at 680 times the legal limit. A few doors down, in the midst of the construction, Eric Fleming took a photo of his two year old daughter, Parker – resting her lips on a windowsill.

"That photo has a different meaning to me now because these windowsills are some of the places that are confirmed universally throughout the building to have some of the highest reported levels of lead," says Fleming.

Communication breakdown

As tenants pieced together what was happening, many came to believe Brady Sullivan wasn’t telling them the full story.

A few examples. Brady Sullivan did eventually email tenants to say lead dust had left the construction site, but only after the New Hampshire Union Leader reported that fact. Then Brady Sullivan organized a forum to educate tenants about health risks and cleaning efforts, but only after tenants posted fliers indicating their intention to sue.

The Environmental Protection Agency and Department of Health and Human Services confirm that after Brady Sullivan sent an initial email that omitted essential facts, regulators began editing emails from Brady Sullivan to tenants.

Brady Sullivan declined to comment on the specific points raised in this story. In an earlier interview, though, the company's attorney put blame for lead dust on the contractor. When asked about statements to tenants and the press later shown to be false, the attorney said, “When those statements were made they were believed to be true.”

In fact, Brady Sullivan’s communication with tenants caught the attention of the City of Manchester, federal regulators from the EPA and OSHA, and the state’s Department of Health and Human Services, where Beverly Drouin works. The EPA and DHHS confirm that after Brady Sullivan sent an initial email which omitted essential facts, regulators began editing emails from Brady Sullivan to tenants.

"So we wanted to make sure the tenants had the real, honest information," says Drouin. "I don’t know that the tenants know that. And I’m sure there’s a level of distrust at this point."

Tenants were not the only ones claiming they were left out of the big picture. Nineteen days after the problem was first identified, Brady Sullivan promised most tenants it would clean their apartments. Ron Peik’s company Alpine Environmental was one of the lead cleaners hired.

But Peik says he quit, in part, because Brady Sullivan was not giving him the information he needed to clean, including details about how much lead was in what locations.

"It was really a funky crossfire, something I had never been involved in before in 25 years in this business, and we were kind of happy to leave," says Peik.

Questions about quality of cleaning

Cody and Danielle Mattiello set up cameras in their apartment to film Brady Sullivan’s lead cleaners at work. They say the cleaning is substandard.

"We had a camera in our bedroom, and they never went into our bedroom to clean," says Danielle Mattiello.

The tenants’ lead expert says these cleaners are leaving behind dangerous levels of lead.

The Mattiellos and other tenants say Brady Sullivan will not let them break their leases because of lead dust. And at the same time, Brady Sullivan is advertising one month free rent for new tenants at Mill West – its only New Hampshire property with that offer, according to the company's website.

The EPA is threatening to fine or sue Brady Sullivan if the company does not clean up Mill West by the end of July. The EPA is still considering a range of actions, including a potential audit of all of Brady Sullivan’s converted mills in New Hampshire, Rhode Island, and Massachusetts.