jenkins 082206 congress wtc dust ph fraud

8/8/2019 Jenkins 082206 Congress WTC Dust pH Fraud

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These falsifications directly contributed not only to emergency personnel and citizens not takingadequate precautions to prevent exposures, but also prevented the subsequent correct diagnosisof the causative agents responsible for the pulmonary symptoms. Thus, appropriate treatmentwas prevented or misdirected, and loss of life and permanent disability undoubtedly resulted.

The following contrasts the statements from the EPA-funded research claiming the small WTCparticles were not corrosive with statements in the associated 2003 publication. Detaileddiscussions are provided later.

Neutral pH (non-corrosive) claims for smallparticle WTC dust

High pH (corrosive) claims for small particleWTC dust

2/11/02 Senate testimony from New YorkUniversity

[T]he less than one percent that was as PM2.5, orthe particles that would reach deepest in the lung,was found to have a neutral pH, with nodetectable asbestos or fiberglass ...

2004 Environmental Health Perspectives studyMaterials < 2.5 µm in aerodynamic diameter [ this is the same as PM2.5 ] comprised 0.88-1.98% of totalmass. Alkalinity decreased with decreasingparticle size, and particles <2.5µm had a morenearly neutral pH (Lioy et al. 2002; McGee et al.2003). This finding is consistent with the dominantpresence of highly alkaline, coarse cementparticles in the large size fraction.

2003 Environmental Health Perspectives study

pH levels of water-extracted WTC PM2.5 andcontrol samples are shown in Table 5. The pH ofwater-extracted WTC PM2.5 samples beforelyophilization ranged from 8.88 in WTCE to 10.00in WTC8. The alkaline pH results from thebuilding materials comprising much of the dust ...

The pH of lyophilized WTC PM2.5 reconstitutedin unbuffered saline [ pre-neutralized WTC dust ]was very close to neutral (pH 7.36) ... It is notknown why the pH of WTC PM2.5 should beclose to neutral after reconstitution in saline. ...

We conclude that water-soluble Ca containingcompounds were enriched in the WTC PM2.5fraction compared with those in the whole settleddust. ... The likely major acute inhalation hazardsof WTC PM2.5 based on the results from thisstudy are due to the presence of gypsum,calcite, and cement or concrete dustcomponents. ... The high content of gypsum andcalcite in the WTC PM2.5 fraction suggests thatpotentially toxic effects may also extend into the

smaller airways and lung parenchyma.

February 11, 2002 Thurston testimony before Senate subcommittee

On February 11, 2002, Dr. George Thurston, a scientist at New York University with EPAfunding for the World Trade Center environmental assessment, provided the following testimonyto the Senate Committee on Environment and Public Works: 2

Only trace amounts of asbestos were found in our samples. [ contrast this with NYU's later publication that the range was 0.8 to 3% for their samples. ] The less than one percent that was as PM2.5, or the particles that would reachdeepest in the lung, was found to have a neutral pH, with no detectable asbestos or fiberglass. Thus, while ouranalyses are consistent with the government’s conclusion that the WTC dust is not likely to have short or long-termserious health impacts on otherwise healthy local residents, we found that it is very irritating and capable of causing thesymptoms reported by many residents. [emphasis added]

Thurston was clearly and explicitly stating there was no cause for concern for any corrosivecaustic effects from WTC dust exposures deep within the lungs.

2 Thurston, G. D. (2/11/02) Statement of Dr. George D. Thurston, Sc. D. to the Committee on Environment andPublic Works of the United States Senate Re: the Air Pollution Effects of The World Trade Center Disasterhttp://www.senate.gov/~epw/107th/Thurston_021102.htm



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February 13, 2002 email interchange between Thurston, USGS, and Jenkins

On 2/13/02 I emailed Dr. Thurston because I was upset over his 2/11/02 Senate testimonyclaiming the smaller WTC dust particles were not caustic. I expressed disbelief, proffering thealternative hypothesis that the larger surface area to mass of the smaller particles could well

explain any discrepancy between their lower pH (lower alkalinity) results. During samplestorage prior to testing, moisture in the atmosphere could collect on the smaller particles, reactand neutralize them.

I also emailed my hypothesis to Dr. Geoff Plumlee, the U.S. Geological Service (USGS) scientistresponsible for the initial pH testing of WTC dust after the disaster, wherein universally highcorrosive pH levels were found. 3 He also was concerned about the aging of the smaller WTCparticles and their neutralization prior to any opportunity for testing by NYU.

Dr. Thurston referred my inquiry to Dr. Lung Chi Chen at NYU, who was the scientist actuallyresponsible for the pH testing. Dr. Chen did not admit in his email to me that he neutralized thesmaller PM2.5 particles by the saline solution "lyophilization" technique.

The following are excerpts from this email interchange. This interchange is important inestablishing that Dr. Chen was extremely aware of the issue being presented to him both by Dr.Plumlee and myself, namely the selective neutralization of the smaller particles prior to anyopportunity for pH analysis. But he was completely silent on the fact that his laboratory had alsoobserved this same phenomena, because they had artificially neutralized the smaller particles, butnot the larger ones, prior to any pH testing.

____________________________________________________________ ____________________________________________________________ Cate Jenkins02/13/02 12:08 PM

To: [email protected]: Questions on your pH measurements- - - - - - - - - - - - - - - - - - - - - - - -George, I have another question for your that I am sure you can clear up, in the never-ending battle to clarifyhearsay: You are quoted as saying at the 2/11 hearing that in your studies you measured the pH of WTC dusts.You fractionated the dust into smaller, respirable-size particulates, and found that the smaller particles did nothave a high pH (a high pH meaning alkaline or caustic).

Considering the high surface to mass ratio of the small particulates, wouldn’t you be concerned that the high pHwould quickly be neutralized by the moisture in the air? The cause of the high pH would be the presence ofcalcium carbonate without any moisture content (anhydrous calcium carbonate), created by the extremely hightemperatures of the fires burning in the collapse of the WTC.

My questions would be as follows:1. How long was it from the time of generation (time the dust was deposited on the ground directly after being inthe dust cloud) to the time of analysis?2. Under what conditions were the samples maintained to preserve their anhydrous state?

3. Were WTC samples subjected to vacuum extraction and storage with a strong dessicant prior to analysis if infact they were collected almost instantaneously from the time of deposition from any smoke or dust plume?4. Were any experiments performed where the smallest particles of WTC dusts were re-subjected totemperatures comparable to the fires at the WTC to return them to their alkaline state, which would be moresimilar to what their pH was at the time they were in the dust cloud and inhaled by firefighters and policeofficers?

3 St. Louis Post-Dispatch (2/9/02) Caustic dust blankets World Trade Center areahttp://www.nyenvirolaw.org/PDF/StLouisDispatch-2-9-02-CausticDustBlanketsWTCarea.pdf

St. Louis Post-Dispatch (1/13/02) Scientists pull out all stops to test NYC dust. They found it hazardous.



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5. I heard that you said that you aerosolized the finer particulates to study them. What methods did you use?Did you aerosolize them prior to subjecting them to pH measurements? What type of anhydrous conditionswere employed during aerosolization to ensure that the moisture present in the air did not neutralize thealkalinity/caustic nature of the small particulates? 6. Were any of the dusts subjected to pH measurement everin a wet environment outside prior to collection (i.e., rain or fire hoses)?

Thanks again,Cate

____________________________________________________________ ____________________________________________________________ [email protected] (George Thurston)02/13/02 12:37 PMTo: [email protected]: Cate Jenkins/DC/USEPA/US@EPASubject: Fwd: Questions on your pH measurements- - - - - - - - - - - - - - - - - - - - - - - -Lung Chi,Can you please answer these questions regarding the pHanalyses of size=fractionated WTC dust.George...

____________________________________________________________ ____________________________________________________________ Lung Chi Chen <[email protected]>02/20/02 09:30 AMTo: Cate Jenkins/DC/USEPA/US@EPAcc: Thurston <[email protected]>,Mort Lippmann <[email protected]>Subject: Re: Questions on your pH measurements- - - - - - - - - - - - - - - - - - - - - - - -Dr. Jenkins:I am not sure I can answer you questions. We first mechanically separated particles (sieving) with a cut off at 53:m. We then aerodynamically separated the < 53 :m fraction to between 53 -10 :m, 10-2.5 :m, and < 2.5 :m. Wetook a small aliquot from each fraction and suspended in a small volume of distilled, deionized water and used apH meter to measure their pH. We found that the suspensions of the particles larger than 10 :m had a pH above11, for 10 -2.5 :m fraction, pH is above 8, and those < 2.5 : is near neutral.

I am not sure whether this measurement technique is applicable to what you are envisioned. An airborneparticle may absorbed moister if the material made up of the particle is hygroscopic. It will reach an equilibriumquickly with the surrounding air, and at very high relative humidity, may become a droplet. Unless otherchemicals present that may neutralize the pH, I can not see water itself would have any effect.

I hope this help.

best. -- Lung Chi Chen, Ph. D. New York University Schoolof Medicine 57 Old Forge Road Tuxedo, New York 10987Voice: (845) 731-3560 Fax: (845) 351-5472 E-Mail:[email protected]

____________________________________________________________ ____________________________________________________________ Cate Jenkins02/20/02 06:28 PMTo: [email protected]:NYU's pH measurement of fine particulates- - - - - - - - - - - - - - - - - - - - - - - -Jeff, attached is info from Kirk Othmer on cement chemistry, and an email exchange I have been having withNYU. Initially, calcium and magnesium hydroxides are formed, with a saturated water solution of pH up to 13.But that then reacts further with all the other mineral forms. NYU (George Thurston) testified on 2/11/02 at

Clinton/Lieberman's hearing in NYC that:

"Our analyses of the WTC dust samples revealed that some 99 percent of the dust was as particles too large tobe breathed deeply into the lung, being largely caught in the nose, mouth and throat when inhaled. This largedust, however, contained approximately one-third fiberglass, with much of the remainder as alkaline cementdust. This large dust was, therefore, quite caustic and irritating to the eyes, nose and throat, consistent with thenow famous "World Trade Center cough"... The less than one percent that was as PM(2.5), or the particles thatwould reach deepest in the lung, was found to have a nuetral pH, with no detectable asbestos or fiberglass."

I have been conversing with NYU on the matter, my theory being that the smaller particles could also have beenalkaline, but nuetralized with atmosheric moisture, or just common rain, due to their high surface area to massratio. What are your thoughts on the subject?

Cate Jenkins 703/308-0453



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____________________________________________________________ ____________________________________________________________ Geoffrey S Plumlee <[email protected]>02/21/02 12:52 PMTo:Cate Jenkins/DC/USEPA/US@EPA cc:Subject:Re: NYU's pH measurement of fine particulates- - - - - - - - - - - - - - - - - - - - - - - -Hi Cate-

The NYU results are quite interesting. I am glad that there are others who are working on the alkalinity of thedusts. It is not clear from the procedure described in the NYU email whether the NYU folks added the samemass of dust to the same amount of water for each of the size fractions. If not, then the differences in pH mayreflect at least in part a progressive dilution of the dust by water at increasingly finer particle sizes (ie there isless of the dust at the finer sizes, that would therefore not have as much portlandite, etc., as the coarser sizes,and that would therefore not shift the pH to as high a value as the coarser particle sizes).

If they did indeed add the same mass of dust to the same amount of water for each of the size fractions, thenthe variations in pH between different size fractions could potentially ref lect variations in the extent ofinteractions of the dusts with slightly acidic water vapor or rain water (the acidity coming from carbonic acid, ±low concentrations of sulfuric and nitric acids, found in rain). It could be that the smaller particles react morecompletely and more rapidly with rain or water vapor, and therefore would show a less alkaline pH than thelarger particles.

Based on my experiences in sulfide oxidation and acid-mine drainage generation, I have seen cases wherereactive sulfide mineral samples stored in sample drawers pull moisture from the air, oxidize, and form sulfuricacid droplets - I suspect that reactive concrete powder could similarly pull moisture from the air and becomeprogressively neutralized.

I think that it would be possible to grind up concrete and separate it into the same sorts of size fractions thatNYU used so that this hypothesis could be tested. I would put the different size fractions in humidity cells (whichare typically used to test the acid-generating capacity of mine wastes) for a given length of time, then do the pHtests. It would be interesting to measure how rapidly the fine particles react and lose alkalinity as a function ofthe relative humidity and temperature of the air - this could play in to whether or not people who inhaled thefinest dust fractions on or right after September 11th may have inhaled "fresher", more reactive and alkalineparticles.

Many Regards, Geoff Plumlee

[email protected] Geoffrey S. Plumlee, Ph.D. Research Geochemist U.S. Geological Survey Crustal imagingand Characterization Team MS964 Denver Federal Center Denver, CO 80225 303-236-1204, FAX 303-236-1229 [email protected]

____________________________________________________________ ____________________________________________________________ Cate Jenkins02/21/02 03:47 PMTo: [email protected]: Thurston <[email protected]>, Mort Lippmann <[email protected]>,[email protected] Subject: NYU pH studies of WTC dusts- - - - - - - - - - - - - - - - - - - - - - - -Dr. Chen,

Thank you for your clarification of 2/20/02. Attached are excerpts from the Kirk-Othmer Encyclopedia on thereactions that calcined (heated to high temperatures) uncured cement undergoes with the addition of water.Initially, calcium and magnesium hydroxides are formed. This accounts for the fact that dry, uncured cement, ina saturated solution with water, can have a pH of up to 13, which is quite alkaline.

However, on subsequent reaction of the hydroxides with the other mineral materials present, other reactionstake place, resulting in the formation of gels and eventually the crosslinked cured cement product itself, which

is no longer alkaline. In other words, the alkalinity of new cement powder when water is added is temporary.With the fires and high temperatures present during the collapse of the World Trade Towers, the cement-likematerials were essentially re-calcined and converted back to uncured, reactive cement. The resulting dusts,therefore, were found to be highly alkaline by both the US Geological Survey as well as yourself at NYU.

I raised the question of whether or not your group’s failure to find alkalinity in the very small particle fraction ofWTC dusts could be due to the fact that the very high surface-to-mass ratio of these particles could result in themore rapid neutralization of the particles with either rain or moisture in the air on storage.

As you can see from the below attached correspondence, I also forwarded my hypothesis to Dr. Geoff Plumleeof the US Geological Survey, who has also studied the alkalinity of WTC dusts. He has suggested a confirmingexperiment of grinding uncured, powdered cement (under anhydrous conditions, of course), then fractionating itinto small particles as you did for WTC dusts (under strict anhydrous conditions), and then immediately testingthe pH. Alternatively, in my original correspondence to Dr. George Thurston, there might be an easier



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experiment, namely heating the small, fractionated portions of WTC dusts to temperatures similar to thosefound in the WTC. Then the pH could be tested immediately. This would be helpful, I believe, in elucidating,diagnosing, and treating the health problems of those who were exposed to the dusts as they existed at thetime they were inhaled.

Thank you very much,

Cate Jenkins

____________________________________________________________ ____________________________________________________________

Associated 2003 study found that fine WTC PM2.5 particles were highly caustic (high pH)

An associated study was published in 2003 in Environmental Health Perspectives (EHP), fundedby EPA, and authored by many of the same scientists .4 One of the co-authors of the 2003 studywas the same Dr. Lung Chi Chen at NYU that corresponded by email with both Dr. Plumlee andmyself in 2002.

The 2003 EHP study found that the smaller PM2.5 WTC particles were equally caustic and ascorrosive as the larger particles. Furthermore, the 2003 EHP article also clearly stated that thesesame small WTC particles were enriched with water soluble calcium compounds like calciumcarbonate, which would cause the corrosive properties.

Fires at the WTC site continued for several months before finally being extinguished, and recovery andreconstruction efforts contributed to emissions of fine [particulate matter with a mass median aerodynamicdiameter (MMAD) < 2.5 µm; PM2.5], coarse (> 2.5 and < 10 µm; PM2.5–10), and larger (> 10 µm) PMfractions....The dust particles from the WTC site appear to be quite alkaline in nature ......Analytical chemistry of aqueous extracts of samples. pH and endotoxin levels. pH levels of water-extractedWTC PM2.5 and control samples are shown in Table 5. The pH of water-extracted WTC PM2.5 samplesbefore lyophilization ranged from 8.88 in WTCE to 10.00 in WTC8. The alkaline pH results from thebuilding materials comprising much of the dust , most likely the alkaline earth (Ca, Mg) compounds.Calcium carbonate, identified by XRD, is a major component of cement (McKetta 1978) and other building

materials. It is almost insoluble in water (14 µg/mL), yet a saturated solution produces a pH of 9.4 (Weast1985). For a 2 mg PM/mL ratio, this requires < 7 µg soluble calcium carbonate/mg PM. Such a level is easilyattainable in the WTC samples, given the percent ranges of Ca and carbonate carbon measured by elementaland OC/EC/CC analysis. The pH of lyophilized WTC PM2.5 reconstituted in unbuffered saline was very close toneutral (pH 7.36), whereas MSH was only slightly acidic (pH 6.61) and ROFA was moderately acidic (pH 3.74).It is not known why the pH of WTC PM2.5 should be close to neutral after reconstitution in saline....

Table 5. pH and endotoxin levels of PM 2.5 samples [ endotoxin levels in table deleted ] ______________________________________________________________________ Sample pH in pH in salinecode water [after pre-neutralization by "lyophilizing" ]

Extractionwater

5.28

WTC8 10.00WTC11 9.16WTC13 9.47WTCB 9.54WTCC 9.32WTCE 8.88WTCF 9.55SRM 1649a 4.20Sterile saline 6.67

4 John K. McGee, Lung Chi Chen, et al. (2003) Chemical Analysis of World Trade Center Fine Particulate Matterfor Use in Toxicologic Assessment. Environmental Health Perspectives, 11(7): 972http://www.ehponline.org/members/2003/5930/5930.pdf



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WTCX 9.35 7.36MSH 6.61ROFA 3.74

_______________________________________________________________________

We conclude that water-soluble Ca containing compounds were enriched in the WTC PM2.5 fractioncompared with those in the whole settled dust. Additionally, the WTC PM2.5 samples were remarkablyhomogeneous in their overall elemental content, considering the wide geographic range of sample collection.

These results were unexpected, given the complexity of the building material composition and scale of thedisaster. However, they are reasonable, considering the prevalent use of gypsum in building materials such asceiling tiles, wallboard, and cement, and the ease with which these materials can be crumbled into a f inepowder, mix, and homogenize.

The likely major acute inhalation hazards of WTC PM2.5 based on the results from this study are due tothe presence of gypsum, calcite, and cement or concrete dust components. Both gypsum and calciteirritate the mucus membranes of the eyes, nose, throat, and upper airways (Stellman 1998). Calcium carbonatedust causes coughing, sneezing, and nasal irritation (NLM 2002). These symptoms of inhalation exposure aresimilar to those reported by rescue and cleanup workers in the immediate aftermath of the WTC attack (Kelley2001). The high content of gypsum and calcite in the WTC PM2.5 fraction suggests that potentially toxiceffects may also extend into the smaller airways and lung parenchyma. [emphasis added]...

The 2003 EHP study also describes the artificial laboratory neutralization of only the smaller

WTC PM2.5 particles prior to pH testing. After pre-neutralization, predictably the pH testsshowed that the small WTC PM2.5 particles were now neutral and not corrosive.

2004 study co-authored by Landrigan, Lioy, Thurston, Chen, Geyh, Levin, others falsifiedfindings in the 2003 study

In 2004, the same scientists, joined by others, published another study in the journalEnvironmental Health Perspectives (EHP), 5 also funded by EPA. Very different statements weremade about the pH of fine WTC dust: :

Dust pH was highly alkaline (9.0-11.0). Mice exposed to WTC dust showed only moderate pulmonaryinflammation, but marked bronchial hyperreactivity....To assess the composition of settled dust by size, samples were mechanically sieved and then separatedaerodynamically into three fractions (Lioy et al. 2002; McGee et al. 2003). More than 95% of the massconsisted of particles larger than 10 µm in diameter. The largest mass concentration consisted of particles of >53 µm in diameter, and there were proportionately more particles in this large size range in outdoor than inindoor samples. Materials < 2.5 µm in aerodynamic diameter comprised 0.88-1.98% of total mass. Alkalinitydecreased with decreasing particle size, and particles <2.5µm had a more nearly neutral pH (Lioy et al.2002; McGee et al. 2003). This finding is consistent with the dominant presence of highly alkaline,coarse cement particles in the large size fraction.

It is important to note that falsifications of the pH levels of fine WTC dust did not first occur inthis 2004 EHP publication. Both Dr. Thurston and Dr. Chen, at a minimum, were making thesame false claims in February, 2002 through first Senate testimony and also by way of theiremail interchange with Dr. Plumlee and myself. Undoubtedly there are other publications and

5 Philip J. Landrigan, Paul J. Lioy, George Thurston, Gertrud Berkowitz, L.C. Chen, Steven N. Chillrud, Stephen H.Gavett, Panos G. Georgopoulos, Alison S. Geyh, Stephen Levin, Frederica Perera, Stephen M. Rappaport,Christopher Small, and the NIEHS World Trade Center Working Group and Sheung P. Ng (2004) Health andEnvironmental Consequences of the World Trade Center Disaster. Environ Health Perspect 112:731–739.http://ehp.niehs.nih.gov/members/2004/6702/6702.pdf

NIEHS through the Superfund Basic Research Program (P42 ES07384 at Mount Sinai and P42 ES05948 atUNC) and through the Centers for Environmental Health Science (P30 ES09089-04S; at Columbia; P30ES00260 at NYU; P30 ES03819 at Johns Hopkins; and P30 ES05022 at UMDNJ); by EPA through theParticulate Matter Health Research Center Program (R827351 at NYU) and a university partnership betweenNERL and EOHSI (CR-827033 at UMDNJ)



August 25, 2006

E.P.A. Whistle-Blow er Says U.S. Hid 9/11 Dust DangerBy ANTHONY DePALMA

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

Page 1 of 3E.P.A. Whistle-Blower Says U.S. Hid 9/11 Dust Danger - New York Times

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http://www.nytimes.com/2006/08/25/nyregion/25toxic.html?pagewanted=print



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.

Page 2 of 3E.P.A. Whistle-Blower Says U.S. Hid 9/11 Dust Danger - New York Times

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jenkins 082206 congress wtc dust ph fraud

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