Lead analysis indicates minimal effect from W.T.C.

Lead was the most common contaminant found among the 263 Lower Manhattan apartments the E.P.A. tested for a range of possible 9/11-related toxins, according to results released on Dec. 8. Of the 222 apartments E.P.A. contractors tested before and after cleaning, 70, or 31.5 percent, had lead levels before cleaning that exceeded the agency’s conservative benchmark of 25 micrograms per square foot.

Cities often have high background amounts of lead, experts say, making it difficult to pinpoint whether the amounts found in Lower Manhattan apartments come from the World Trade Center or other sources that can include lead found in paint or soil.

The E.P.A. results “clearly reflect the prevalence of lead throughout the city and in most urban cities,” said Dr. Joel Foreman, the director of pediatrics at the health specialty unit at Mount Sinai.

“I’ve yet to see information that convinces me that there’s a lead hazard directly from the World Trade Center,” Foreman said. Elevated lead levels are a health concern regardless of the source, he added.

Out of the 1544 wipe samples the E.P.A. took overall in over 200 apartments, 6.22 percent had lead levels over 40 micrograms per square foot, and 8.81 percent had levels over 25 micrograms per square foot. Forty micrograms per square foot is the standard used by the Department of Housing and Urban Development, and the E.P.A. adopted 25 micrograms as its standard for its Downtown cleanup.

One reason why scientists cannot determine the exact source of the lead found Downtown after Sept. 11 is that no comparable tests were taken in Lower Manhattan apartments before the trade center collapse. The E.P.A. tested and cleaned in apartments south of Canal, Pike and Allen Sts., and the background levels of lead in those apartments before 9/11 would be difficult if not impossible to determine without prior data, experts say.

“It’s not uncommon to see elevated dust lead levels” in New York City, said Dr. Jessica Leighton, an assistant commissioner with the New York City Department of Health and Mental Hygiene.

Even so, the health department studied the blood lead levels of Lower Manhattan children between Sept. 11, 2001 and Dec. 31, 2001 and found lower amounts than in the city as a whole, Leighton said. Children under seven are particularly susceptible to lead poisoning, which can cause cognitive defects and a lowered I.Q.

Catherine McVay Hughes, a member of Community Board 1 and an environmental activist, cautioned that the child blood lead statistics may not be a fail-safe indicator of Lower Manhattan children’s lead exposures. Children’s blood lead levels should be tested at ages one and two, but parents must be vigilant in requesting a blood lead test since pediatricians do not always perform these tests as needed, said Hughes, the mother of two boys. On Monday, the New York City Council passed a bill calling for more stringent protections against childhood lead poisoning, including an increase in building owners’ responsibilities to protect tenants with small children.

The E.P.A. began its voluntary residential cleaning and testing program nearly one year after the terror attacks, and apartments were still being sampled this spring. This time lag also makes it difficult to gauge the source of elevated lead, experts say.

“Lead does accumulate,” said Dr. Jack Caravanos, a professor of Environmental Health at Hunter College, who studied personal exposures to dust and volatile organic chemicals from the Twin Towers’ collapse.

In other words, Caravanos explained, lead from usual urban sources can pile up if surfaces are not regularly dusted with a wet cloth. Caravanos and his team wipe glass plates every week at their E. 25th St. offices and test the dust samples for lead. About 10 micrograms per square foot accumulates per week, he said.

Therefore, an apartment that had gone unoccupied after Sept. 11, 2001 might have tested high for lead simply because no one had been around to clean it for a while, Caravanos said.

But the prevalence of background lead does not rule out the World Trade Center as a possible source of the lead found in some Downtown homes, Caravanos and others have said. Even though the Twin Towers were built after the city banned the use of lead-based paint in 1960, some trace levels of lead could likely have been present in W.T.C. paint, Caravanos said. In addition, lead could be found in some old computers and in plumbing, Hughes said.

“Using logic, we know some of the lead comes from the World Trade Center,” said Mary Mears, a spokesperson for the E.P.A.

To help the E.P.A. determine the source of elevated lead in some Downtown apartments, the agency could have tested for lead-based paint in the apartments where it conducted wipe sampling, Foreman said. These tests cost between $500 and $1,000 per apartment, Foreman said, and they could possibly eliminate lead paint as a source.

The E.P.A. has spent just under $10 million on its voluntary residential cleaning and testing program to date, Mears said, with the full amount funded by the Federal Emergency Management Agency. The E.P.A. does not normally conduct lead-based paint tests and did not consider doing so as part of its Lower Manhattan cleanup, Mears said.

The E.P.A. will not go back and re-clean apartments where it found elevated lead, officials have said. Instead, the agency gives information to residents about cleaning methods to help reduce toxins.

Hughes said that the real issue is not where the lead comes from. She urged the E.P.A. to take responsibility for its wipe test results: “Regardless of what the source was it should be cleaned and it should be a wakeup call to test for more.”

Elizabeth@DowntownExpress.com