Of the 431 workers from the original group who were still living, 280 participated in the follow-up study and were interviewed about their lung health and work history, including particular exposure level and the numbers of years they worked. They were then given chest x-rays, which were assessed for pleural plaques, thickening and interstitial changes by professional radiologists.
When the researchers analyzed the workers with pleural changes by exposure levels, they found a significant trend of increasing changes with increased exposure. Workers with highest exposure levels had an average of 6 to 16 times the risk of pleural changes when compared to those who were minimally exposed. Moreover, the changes were significant even at levels of exposure currently permitted by law.
The findings indicate that “a significant number of workers exposed at the current limit would experience pleural abnormalities,” wrote Gregory Wagner, M.D., of the National Institute for Occupational Safety and Health, in an accompanying editorial.
Furthermore, regulations governing legal exposure limits to hazardous materials apply only to specific fibers, not to all types of fibers that have similar and predictable biological effects.
“When humans are exposed to any mineral fibers that are long, thin and durable in human tissue and can reach the pleural membrane, these fibers can cause health problems,” said Dr. Lockey. “Six types of asbestos are currently regulated, but other existing types of fibers that share similar characteristics are not.”
Perhaps most importantly, the research highlights the need to anticipate the health implications of occupational exposures.
“The initial Lockey investigation found a relatively modest prevalence of pleural abnormalities,” wrote Dr. Wagner. But the current study “found over 10 times that level, despite the fact that contaminated vermiculite had been removed from the production process by 1980.”
That italicized thing, radiologists indicate a belief about "mineral fibers that are long, thin and durable in human tissue" being problematic even when exposure levels were below present thresholds - that sure makes that Zanko geological engineer up at NRRI in Duluth look "exposed" beyond a reasonable limit too. Not to asbestos, but to criticism for delving where his expertise is inadequate - health and exposure issues.
Then this -- We see, 2007, PubMed has an abstract for an article not openly published in full on the Web; but the ending sentence from our very own Minnesota DNR is important:
Asbestos first became an issue to Minnesota's iron industry when it was revealed that mineral fibers similar to those in Reserve Mining's tailings were being found in drinking water for several communities that used Lake Superior as their primary water source. This discovery turned what had largely been an environmental court battle into a case concerning public health. The courts listened to much conflicting and uncertain scientific testimony on the size and distribution of the mineral fibers and on the potential health effects imposed by them. In April 1974, the plant was ordered to shut down by a federal judge but the company quickly appealed the decision. The appeals court granted a stay and ultimately ruled that the plant's closure could not be justified based on the unknown health effects of the mineral fibers since the consequences of such an action would have immediate and severe social and economic impacts. The plant was allowed to continue operation, but ordered to abate emissions to air around the plant and to switch to a land-based tailings disposal system. Much of the scientific uncertainty and public concern over mineral fibers in Minnesota's taconite industry remain today.
So - then we see the lab that Zanko's study relied upon, the one in Pennsylvania, the Lee lab, splitting hairs over "fibers" and long, thin, pointy "cleavage fragments" that are from minerals close in chemical makeup to asbestos "fibers."
Does that suggest the Zanko-labjockies etc., are sufficiently risk averse, to you, with your health risks? Not to me, no sir.
This to me sounds like pure lies, sophistry and excuse-making -- and hairsplitting over "fibers" when that above language was about "mineral fibers that are long, thin and durable in human tissue" and you look at some of the stuff, in the illustrations the Lee-Zanko labjockies offer in pictures, sharp points and all, while saying the functional equivalent of "Don't worry, be happy," to the MHSA, Mine Health and Safety Administration, a federal agency,
All of the identified particles shown in these photographs fail to meet the minimum definition of a fiber – there are no parallel sides on these particles. The laboratory acknowledged that these particles were not asbestos fibers, but were cleavage fragments ("… the fibers in these photographs were more 'fractured' in appearance …", page 30 of report). To compound matters, MSHA interpreted the data to show the vast majority of counted airborne particles to be asbestos ("… the total percent asbestos … ranged from 85% to 100% …", page 7 of report).
If a correct definition of fiber had been specified in the MSHA regulations, none of the reported particles would have been counted as fibers.
And, so you know what dots connect to others, back to vermiculite, the industry appologists there at work, same BS distinction the Lee-lab people are fobbing off - those pointy mean-looking "cleavage fragments" are not "fibers" because they lack parallel sides. Do you suppose it is the long sharp and durational stability, and chemical makeup, that caused the pleural degenearation reported in the first item; or did "parallel sides" make a big difference. Get serious. Yet, vermiculite advocate-appoligists at "vermiculite.org" are just like the Zanko-Lee crowd:
The elongated particles identified in the air tests as asbestos by the phase contrast light microscope test (PCM) were further analyzed by the more powerful electron microscope (TEM). These particles had the width and length typical of “cleavage fragments” under OSHA’s protocol 29 CFR 1926.1101 Appendix B2 and none of the particle widths were less than 0.1 to 0.2 microns which is the reported diameter of true actinolite-tremolite asbestos fibers.3 The fact that the particles identified as asbestos fiber were single fibers and were never found in bundles by EPA, OSHA or NIOSH is a further indication that the particles are likely to be cleavage fragments.4 Another test, the “Fibrosity Index”,5 which is a statistical method to identify “cleavage fragments” from “true asbestos”, shows these particles are cleavage fragments. The NIOSH reports did not differentiate actinolite-tremolite cleavage fragments from true asbestos nor did they calculate a Fibrosity Index.
So it's parallel sides, and a "Fibrosity Index" or some such that has Zanko saying it's safe for you and your family, in the paving in front of the home.
Closing question, do you suppose the bike trails this guy uses are paved with taconite tailings for which he'd sense no risk? If all the animals on Animal Farm were equal, it might be, but ... I just bet the trail-riding bike jockey has cause to smile broadly and safely, on HIS trails.
The Tinklenberg credibility gap IS widening.
And as a part of it, the date on this spec is Dec. 2007, but when do you suppose that p.3 thing about taconite tailings being an approved aggregate item, for MnDOT, as long as East is East and West is West, -- as a thought experiment, who might have been MnDOT commissioner when that specification was first approved? I do not know. I could only find this document, without any administrative history behind it.
But, again, the onus is on Elwyn Tinklenberg to explain himself. To say, "During my watch, I did it," or to say "Not during my watch." Then the fact-checking the GOP probably already has done, bent gussets and all - half as thick as they should have been - in 2003 where during prior years, before Oct. 2002, the view under the bridge could not have been too different. So, fact checking, Tink was or was not MnDOT commissioner when that p.3 "go ahead and use the junk" text was first promulgated; and he was MnDOT commissioner when the bridge gussets were half the right thickness and bent; and he says, "Metallurgy."
And, "Approved taconite tailing sources are on file with the Department Bituminous Engineer," being the 2007 MnDOT story, just when did the "Department Bituminous Engineer," collect (or more likely have handed to him) the "approved taconite tailing sources?" Tinkster, are you there? What's the story?
Finally, feature this, even if that spec came into being Dec. 2007 for the first time, did it do so, as part of a "logistics and marketing" contract effort, out of Tinklenberg Group? There's some 'splaning due, that is for certain.
BOTTOM LINE: The man has an awful lot of baggage to think he would be hauling it all to DC to take over the Michele Bachmann seat.
Hubris.
Hubris and baggage. It defines the man.
______POSTSCRIPT_________
I gave my thinking in an earlier post about sampling - good protocol and bad. Apparently it was no twenty samples from around each pile, but a TOTAL of eighteen from the various piles, and then the Lee lab did the lab work, guys and gals peering through microscopes, etc., and they as well as Zanko have advacatorial positions publicly advanced. It is like the concern some are expressing for pharmaceutical company funding of drug screening clinical tests. The incentive to call the close pitches one way rather than the other exists if the umpire is being paid by one team, not the league. Or if the umpire "likes" one team's image over the other. Or if he has background ties, one way or the other.
I don't think the sampling is clear; and I would prefer the lab work done by a university lab and not an outfit like the Lee lab, with its "cleavage fragment" distinctions from "fibers" having "parallel sides."
I think the vermiculite people are correct in pointing out, fiber bundles are different from isolated cleavage fragments - more threatening - but how many particles, puncturing and lodged into lung tissue does it take to start a cancer?
I sure doubt the Lee lab techs, Zanko, or Tinklenberg know that answer. I believe it fits with the DNR comment, quoted above, Much of the scientific uncertainty and public concern over mineral fibers in Minnesota's taconite industry remain today. With El. He is certain where his cash flows from. Independent of any "scientific uncertainty" he knows that - since his contract is not about science, but about logistics and marketing. Huckstering is not the heart and soul and core of the scientific method.