E.P.A. Whistle-Blower Says U.S. Hid 9/11 Dust Danger

By ANTHONY DePALMA

08/05/06 "New York Times" -- -- A senior scientist at the Environmental Protection Agency has accused the agency of relying on misleading data about the health hazards of World Trade Center dust.

The scientist, who has been sharply critical of the agency in the past, claimed in a letter to members of the New York Congressional delegation this week that test reports in 2002 and 2003 distorted the alkalinity, or pH level, of the dust released when the twin towers collapsed, downplaying its danger.

Some doctors suspect that the highly alkaline nature of the dust contributed to the variety of ailments that recovery workers and residents have complained of since the attack.

Tests of the gray-brown dust conducted by scientists at the United States Geological Survey a few months after the attack found that the dust was highly alkaline, in some instances as caustic or corrosive as drain cleaner, and capable of causing severe irritation and burns.

The tests that are being challenged by the E.P.A. scientist were conducted by independent scientists at New York University. Those tests also indicated that larger particles of dust were highly alkaline. But they found that smaller dust particles — those most likely to reach into the lower airways of the lungs, where they could cause serious illnesses — were not alkaline and caustic.

The geological survey’s tests did not differentiate the dust by particle size.

A spokeswoman for the agency, Mary Mears, said in a statement that the E.P.A. stood behind its work on ground zero environmental hazards, as did the N.Y.U. scientists. The scientist making the complaint, Cate Jenkins, who has a Ph.D. in chemistry and works in the agency’s office of solid waste and emergency response, said the test results helped the E.P.A. avoid legal liability. Residents of Lower Manhattan have sued the agency in federal court, claiming that it bungled the cleanup.

Dr. Jenkins said the test reports had a costly health effect, contributing “to emergency personnel and citizens not taking adequate precautions to prevent exposures.”

In her statement, Ms. Mears distanced the agency from Dr. Jenkins, who has worked for the E.P.A. since 1979 and has been in conflict with the agency for years over her whistle-blowing activities.

“Dr. Jenkins has not participated in any aspect of the E.P.A.’s work on the World Trade Center,” the statement said. “This appears to be a disagreement about scientific methods and not the validity of the results.” The New York University scientists, who were not directly financed by the E.P.A., denied being pressured by the agency and said Dr. Jenkins’s claims were without scientific merit.

Representative Jerrold Nadler, a Democrat whose district includes Lower Manhattan, received a copy of Dr. Jenkins’s letter, and he said that he intended to look into the dispute.

“When a scientist who works for the E.P.A. makes serious allegations about the aftermath of 9/11, they must be examined carefully,” he said.

The two scientists named in Dr. Jenkins’s letter are faculty members of the New York University School of Medicine who collected dust samples from ground zero in the days after the attack.

One of them, George D. Thurston, is director of N.Y.U.’s Community Outreach and Education Program. He has helped inform Lower Manhattan workers and residents about health hazards related to the terror attack.

Testifying before a Senate committee in 2002, Dr. Thurston said that more than 95 percent of the dust was composed of comparatively large particles that were highly alkaline. He said that although they were irritating, those dust particles did not pose serious health concerns for residents because they were too large to enter the lower airways of the lungs.

Smaller particles, those less than 2.5 microns in size, are far more dangerous because they can be easily breathed deep into the lungs. Dr. Thurston told the Senate committee that tests showed those particles to be pH neutral, and therefore of less concern.

A year later, the same scientists, in conjunction with the E.P.A., among others, published a report in Environmental Health Perspectives, a professional journal, in which they described a new round of tests in which they found the smallest dust particles to have pH values from 8.8 to 10, which made them alkaline.

To keep the particles in the samples from congealing, however, they used a standard process that involved freeze-drying and soaking the samples in saline. When pH tested, the particles were then found to be “near neutral.”

Lung-Chi Chen, the second N.Y.U. scientist, an inhalation toxicologist with N.Y.U.’s School of Medicine who was responsible for the testing, said the saline could not have diluted the alkalinity of the samples so greatly that they went from alkaline to neutral.

“We were not trying to mislead anyone,” he said.

Dr. Chen said the samples tested prior to Dr. Thurston’s 2002 Senate testimony and those in the 2003 report came from different batches of dust, which probably accounted for the difference in their alkalinity.

He said he was not surprised that the smaller dust particles had characteristics and alkalinity levels different from the larger ones. He explained that the larger particles were made up of building materials that had been pulverized by the pressure of the imploding towers. The smallest particles, he said, were probably a combination of crushed material and the combustion byproducts produced by high-temperature fires that burned for weeks.

Copyright 2006 The New York Times Company