Monday, July 25, 2005

Money Tox - More on Cambridge Environmental (revised)

BrooklynDodger recently blogged about a review paper discounting risks of particle pollution [abstracted below], now spreading like a virus through the internet as an abstract in Regulatory Toxicology and Pharmacology.

This post was initially going to be a piece of free floating hostility simply attacking the enterprise, but BrooklynDodger recanted, believing these posts should mostly be foundationed by an abstract.

Another paper by the same authors was found:

Clin Occup Environ Med. 2004 Aug;4(3):481-96, vi.

Chlorinated hydrocarbon solvents.

Armstrong SR, Green LC.

Cambridge Environmental Inc., 58 Charles Street, Cambridge, MA 02141, USA.

Chlorinated hydrocarbon solvents, such as trichloroethylene and 1,1,1-trichloroethane, have been used widely in many industries because of their ready ability to dissolve oils, greases, and other materials, their low acute toxicity, and their non-flammability. Although these materials share certain toxicologic, functional, and chemical similarities, important differences exist. These differences largely explain why certain solvents, once common, are no longer in use and why others have become more widely used over time. This article reviews the properties, toxicologic effects of interest, workplace limits, and use history of the most common chlorinated hydrocarbon solvents

BrooklynDodger wonders at the editors of this publication printing an abstract that conveys no information. Actually, in this case, the literature is better served by not propagating the authors' brief over medline.

What's the paradigm, as the Dodger tries to trash the quality of Cambridge Environmental's work?

A high school student can download abstracts, even full papers, and collect quotations supporting one or another view. The point of PhD school is that practitioners can't understand the work unless they have done the work, written and published as well. The authority of a review stands on whether the reviewer has done original original research in the field relevant to the review. But not many original researchers write reviews, and then largely after they have become statespersons of science.

There's a reason why textbook writers, even at the college level, are frequently not muchers, has beens or never weres from the perspective of original research. [Graduate textbooks tend to be compendia of review articles, in turn compendia of abstracts.]

The problem of intellectual synthesis arises because an individual's research generates particles of knowledge, which are meaningless unless held together with the cement of a paradigm to create concrete knowledge [that's a pretty good metaphor, particles should really be aggregate]. The practitioner who may be successful at generating data within a paradigm may not be able to narrate the paradigm or be conversant with the gaps in the paradigm.

For a research university, the key to admission to the faculty is some record of original research. To a degree, conversing with paradigm and its discontents generates quality research. But poor teaching is common, and few scientists are conversant with the notion of paradigm and incommensurability.

In public health areas, the data-synthesis problem intensifies because the work is interdisciplinary, and the key disciplines change from issue to issue. In a mortality study, is absence of exposure-response a consequence of uncertainty in response [epidemiology-biostatistics] or exposure [industrial hygiene]? In a bioassay, does a marginally significant result come from variation in pathologists readings or is it a real departure from historical control rates? Has the author of the review sat in the meeting where co-investigators argued over the conclusion of a single project?

Back to the matter at hand. Where do these people get off with getting their reviews into the peer reviewed literature?

Green LC, Armstrong SR.

Particulate matter in ambient air and mortality: toxicologic perspectives.
Regul Toxicol Pharmacol. 2003 Dec;38(3):326-35.

Green and Armstrong appear as co-authors on one other review found by medline, a description of health effects of chlorinated solvents with an uniformative abstract. However, the provenance of that paper is found below.

Clin Occup Environ Med. 2004 Aug;4(3):481-96, vi. Review.

Armstrong SR, Green LC.

Chlorinated hydrocarbon solvents.

Through the magic of google, the Dodger found Cambridge Environmental, its named staff, and its list of products. The staff includes previously known heavy hitters from the right side of the plate, Crouch and Charnley.

Green is a "senior scientist" and president of the Cambridge Environmental. BrooklynDodger, being an older person, questions whether a 1975 bachelors degree [there is a PhD, but the bachelors is a measure of age] without a university appointment is really "senior." Cambridge sports another "senior scientist" without even a masters degree. "LC Green" is not that easy to search on medline, but the Dodger found no original research in toxicology. Armstrong has a masters degree, usually not enough to get published.

The review of chlorinated hydrocarbon toxicity would appear to be a recycling of this project:

Cambridge Environmental helped a defendant successfully argue a Daubert motion by showing that the scientific testimony of the plaintiff’s causation witness was unreliable. The case had been brought by a young woman what had contracted leukemia and sued the manufacturer of the cleaning fluid, perchloroethylene, used in the dry-cleaning shop where she had briefly worked, claiming that exposure to perchloroethylene had caused her cancer. We took the lead in preparing a joint expert affidavit signed by one of our staff, an epidemiologist, and a hematologist that strongly criticized the scientific method used by the plaintiff’s expert epidemiologist. We offered detailed testimony before the judge and the physician-scientist she had appointed to assist her. The case was dismissed on summary judgment.

The Cambridge environmental website also recounts another regulatory brief which made the literature:

"A private company sponsored our research on the potency of asbestos as a cause of lung cancer. Existing estimates of this parameter had not been updated to account for results from about a decade of epidemiologic research; and prior attempts to combine epidemiologic studies were only semi-quantitative. We assimilated dose-response data from fifteen groups of asbestos-exposed workers detailed in 22 publications, using maximum likelihood techniques to obtain measures of the relationship between cumulative exposure to asbestos and relative risk of lung cancer. Our meta-analysis (Lash, Crouch, and Green, Occup. Environ. Med. 54:254-263, 1997) explored sources of heterogeneity in the dose-response coefficient, generating a potency estimate under a fixed-effect model and another under a random effects model. These estimates were 24-fold smaller and fourfold smaller, respectively, than the OSHA (1986) estimate relied upon for rule-making."

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