Source: The Charleston Gazette (WV), March 18, 2014
Posted on: http://envfpn.advisen.com
Two new reports from an independent team confirmed Monday that people can smell extremely low concentrations of Crude MCHM and that significant data gaps exist that cloud what is known about the potential public health impacts of January’s Elk River chemical spill.
The reports from the West Virginia Testing Assessment Project, or WVTAP, outlined findings about the odor threshold for Crude MCHM and summarized the limited data about the toxicity of that chemical and others spilled into the Elk River on Jan. 9 by Freedom Industries.
Perhaps the most significant new conclusion is one that humans appear to be able to smell the licorice-like odor of Crude MCHM at far lower levels than state officials had previously believed.
The “odor threshold concentration” for the chemical is estimated to be 0.15 parts per billion, according to one of the two new reports made public by the WVTAP team. Previously, state officials had said they were using an odor threshold number of 1.0 part per billion, which they obtained from work done by the Louisville Water Company in Kentucky.
In its other report, a review of potential health effects of the spilled chemicals, the WVTAP team gave a more detailed description than government officials had previously provided, while emphasizing that there is little scientific data about the materials involved.
“Very limited toxicological data has been reported for MCHM Crude or pure MCHM,” says the health effects review, co-authored by Craig Adams, an environmental engineer at Utah State University.
Adams conducted his review as part of the WVTAP project, launched by Gov. Earl Ray Tomblin amid significant public pressure over concerns about lingering and long-term impacts of the January spill at Freedom Industries that contaminated the drinking water supply for 300,000 residents in a nine-county region.
Andrew Whelton, a University of South Alabama environmental engineer who is helping lead WVTAP, said Monday the public should expect a flurry of new reports from the project over the next few weeks.
“There was conflicting and confusing information that was released by various parties as this incident progressed,” Whelton said. “What we’re going to release over the next couple of weeks will address many of the questions the public has and provide a roadmap for going forward.”
In his 22-page health effects report, Adams provided short descriptions of the limited number of studies published about MCHM, PPH and the known constituents of the two major chemicals believed to have been spilled by Freedom Industries.
For many of the constituents, the report simply says that “no toxicology data were listed” in a major U.S. Environmental Protection Agency database of such data.
Also, the report notes “neither the statistical analysis nor control sample data was presented” in a key chemical industry study that the U.S. Centers for Disease Control used to come up with what the CDC called a “screening level” for MCHM.
Interestingly, the report notes that the term “screening level” — used by the CDC and by state officials in West Virginia — “is non-standard terminology for drinking water.” Typically, the report says, drinking water experts use the terms “health advisory,” “drinking water equivalent level” and “reference dose.”
The health effects report also notes that there are various routes of possible exposure to drinking water contaminants, including drinking the water, inhaling steam while taking a shower, or getting it on your skin while bathing. The report said that the various routes are “a relevant topic” to be considered by the WVTAP’s toxicology panel, which will convene later this month or in April.
In the odor report, the major finding was that the “odor threshold concentration” — 0.15 parts per billion — for MCHM is “in the realm of parts per trillion, an extraordinarily low concentration.”
There are 1,000 parts per trillion in 1 part per billion. The odor threshold of 0.15 parts per billion is the same as 150 parts per trillion.
“The ability of the expert human nose to detect this compound is far greater than any analytical method available today,” the report said.
Following the Freedom Industries spill, water company officials and state government representatives repeatedly told the public that Crude MCHM from the Elk River chemical leak had a low odor threshold. Residents would smell it in their water at levels far below what was dangerous, officials said.
The problem was the “material safety data sheet” from Eastman Chemical, which made the chemical that leaked from Freedom Industries, said there was “no data available” on Crude MCHM’s odor threshold.
As part of the WVTAP project, California environmental consultant Michael McGuire convened an “odor panel,” in which trained experts use their sense of smell to try to project what concentrations of a chemical humans can detect.
The report defined the “odor threshold concentration” as the chemical concentration usually determined in a laboratory setting, where about 50 percent of human panelists can detect the odor of a chemical.
The report included two other numbers.
One was the “odor recognition concentration,” defined as the level where half of the panelists can correctly recognize and describe the odor characteristics of the chemical. For MCHM, that concentration was 2.2 parts per billion, the report said.
The other was the “odor objection/complaint concentration,” defined as the level that causes consumers to object to their water supply and to call and complain. For MCHM, that concentration was 4.0 parts per billion, the report said.
The WVTAP report said that the findings “support consumer observations” that “people recognized and objected to the licorice odor caused by Crude MCHM in their drinking water, even though the analytical reports were showing non-detect” using a test method that reported results when concentrations of 10 parts per billion or greater were found in water.
“Not surprisingly, many people in Charleston did not use tap water even after the ‘Do Not Use’ restriction was lifted,” the report said. “They also did not start using tap water after they were told that the concentration of MCHM was non-detect.
“They continued not using tap water because their sense of smell recognized it and objected to its presence,” the report said. “For many people, smelling an off-odor in tap water means that it is not safe for them to drink.”
Federal officials had encouraged the state government to advise residents to flush their home plumbing systems until they no longer smelled the licorice odor, but the state declined to follow that federal recommendation.
West Virginia American Water officials have said their system could not have sustained that amount of flushing, and the region would have run out of water for sanitation and firefighting.