National Academy of Sciences did their study here.

In it’s investigation of a Groundwater contamination at Camp LeJeune the National Academy of Sciences Expert Panel  (see page 8 of 12 especially) concluded:

” The majority of the health outcomes reviewed by the committee were placed into the category of inadequate/insufficient evidence to determine whether an association exists, which means that the studies were too few in number, limited in quality, inconsistent, or inconclusive in results to make an informed assessment. It also means that such an association cannot be ruled out. For diseases and disorders in this category, the committee has concluded that the epidemiologic studies cannot tell us whether exposure to the chemicals is associated with the disease or not.”

Regarding those cases where  the evidence was suggestive of an association the National Academy’s report had this to say:

“The strongest evidence was in the category of limited/suggestive of an association, which means that there is some evidence that people who were exposed to TCE or PCE were more likely to have the disease or disorder but that the studies were either few in number or had important limitations. In many cases, the studies could not separate out the effects of individual chemicals because the people were exposed to mixtures. Some of these studies were of highly exposed groups of workers where detection of effects would be expected if present. Such studies might reach conclusions about solvents in general but not about TCE or PCE specifically. For diseases and disorders where the evidence is limited/suggestive of an association, the committee has concluded that the epidemiologic studies give some reason to be concerned that sufficiently high levels of the chemical may cause the disease, but the studies do not provide strong evidence that they actually do so. “

In the EPA’s just released Integrated Risk Information System  final risk assessment for trichloroethylene, they ignore the National Academy of Science’s expert opinions on the science  of Trichloroethylene. “The studies do not provide strong evidence...”

In the EPA’s latest IRIS assessment, EPA characterizes TCE as “carcinogenic to humans and a human noncancer health hazard.”

EPA 's Science

They state that “TCE is characterized as  “carcinogenic to humans” by all routes of exposure.  This conclusion is based on convincing evidence of a causal association between TCE exposure in humans and kidney  cancer.”

 According to National Academy of Science “the studies do not provide strong evidence.”

National Academy’s “No strong evidence” is EPA’s “Convincing evidence of a causal association.”

We wonder why the EPA decided not to heed the National Academy of Science-‘s findings- they were good enough for the Dept. of  Navy and the Marine Corps?

We wonder what are the criteria that help EPA to decide when to believe the National Academy of Science and when not?

We wonder why EPA failed to take into account comments by the public and other government agencies when creating this assessment?

We wonder why evidence the National Academy of Sciences characterized as “limited or suggestive of an association” became “convincing” to the EPA?

We wonder is this just another regulatory effort to curtail manufacturing jobs in the United States?

What do you think?

For more info on TCE

HSIA information regarding the EPA’s latest assessment on TCE.

She Blinded me With Science

As machinists, we are used to handling materials in the bulk world.
As machinists, our ease in obtaining productivity is influenced by the microscopic world of phases, microstructures, and chemistry.
Underneath this microscopic world lies the world of molecules  and atoms themselves.
This is the chemical formula for pentacene. It is used in organic thin film transistors.
Recently researchers from IBM research team in Zurich used an atomic force microscope to capture an image of a single molecule of this substance.

Compare to the structure above.
Compare to the structure above.

This image of a single molecule shows the five rings of six carbon atoms and suggests the hydrogen bonds along the edges.
The precision needed to resolve at this atomic level requires both extremely high vacuum and frighteningly cryogenic temperatures. And you thought you had temperature control issues in your metrology lab.
Our industry will not be at this atomic-level nanoscale any time soon, at least not for our production processes.
We hope this glimpse of what makes up our material world from the frontiers of science gives you a better appreciation for the work of all the chemists, metallurgists and engineers in the supply chain that produce our raw materials, tools, and metalworking fluids. For all of history, scientists have struggled to  make sense of their observations, develop theory, structure and formulas that made sense. This IBM image confirms that we’re on the right track.
Full story care of BBC .