Many backyards in Greenpoint likely contain dangerous levels of lead, according to preliminary findings from a group of Columbia University graduate students.

A team of researchers led by Franziska Landes, a graduate student in the Department of Earth and Environmental Sciences at Columbia, have studied 264 soil samples from 52 private backyards since this spring, according to a report from Columbia's Earth Institute. It is the most comprehensive Greenpoint soil lead analysis to date.

Preliminary findings show that 92 percent of yards have at least one soil sample with lead levels higher than what the Environmental Protection Agency deems safe for humans. (Of 463 samples taken from public parks and sidewalks, only about 14 percent were in the danger zone.)

"I think this confirms a long-held suspicion with some community members that there's an issue, whether it relates to paint or lead in water or soil," said Alan Minor, chair of Neighbors Allied for Good Growth, a North Brooklyn environmental advocacy group. NAG recently received a grant to host workshops on lead exposure in the community, and connected with Landes, who offered to conduct soil tests in the community free of charge.

"This is a neighborhood, Greenpoint and Williamsburg, that has been heavily polluted over the last century-plus through industry, through the BQE, and lots of air pollution as a result," Minor added. "We figure that some of the lead in soil may be coming from that: leaded gasoline over the years."

Children under the age of six are most susceptible to lead poisoning, according to the NYC Department of Health. Tap water from lead pipes can pose a risk, as well as chipping lead paint in apartments and lead dust in soil. Exposure can impact a child's development and result in learning disabilities.

"This finding is deeply concerning," City Councilmember Steve Levin, who represents Greenpoint and Williamsburg, told Gothamist in a statement. "No child should be exposed to lead in their home and this includes their backyards. I'm grateful of the dedicated individuals working to understand the scope of the problem."

Levin added that he plans to work with DOH to expand regular testing methods.

"Here in Greenpoint we've dealt with contamination of one sort or another for decades," Levin said. "Realistically speaking, we will be dealing with the legacy of industry and environmental waste for decades more. Regardless, our responsibility is ensure the health and safety our residents."

As Levin pointed out, parts of Greenpoint are still coping with toxic pollution resulting from decades of dumping from dry-cleaning and metalworking businesses in the neighborhood, as well as other industries. High levels of phthalate and TCE have been detected around the former site of the Nuhart Plastics factory, a state Superfund site. And then there's the infamous Greenpoint blob, a 50-acre-wide subterranean stretch of petroleum and other toxic pollutants spilled by the oil refineries and storage facilities that formerly lined Newtown Creek—now a Superfund site. (A 2015 map attempted to mark the area's worst-polluted spots.)

NYC DOH has documented Greenpoint's high lead exposure in the past. A 2014 DOH report shows that Greenpoint children show elevated lead levels at about four times the rate of children elsewhere in NYC.

A spokeswoman for DOH declined to comment on the Columbia findings, as the city has yet to review them. However, she pointed to city data that the number of children with elevated blood lead levels has declined 70 percent city-wide since 2005.

"The next step is really to do a thorough study and find out the extent [of the problem]," Minor said. "It would be wonderful if we could... conduct a study that included soil, water and paint."

"The step beyond that is figuring out a remediation plan," he added. "There has been discussion of starting a clean soil network.... Right now the Office of Environmental Remediation has a program where it works with developers and construction contractors: clean soil is being excavated from a site and immediately picked up by another contractor. So, soil as commodity.... Right now, the two primary challenges are finding storage for the clean soil and distributing it an equitable manner."

Covering soil with grass or mulch can reduce the risk of lead exposure, according to DOH. Children who play outside should wash their hands frequently and take shoes off when coming indoors.