The former owner of a St. Joseph, Mo., tannery that is being sued over health concerns acknowledged that the plant used a cancer-causing chemical, but he said the tanning process posed no danger to the public.
The former Prime Tanning plant in St. Joseph has been sued over concerns that sludge it distributed to farmers to use for fertilizer contained chromium 6, a known carcinogen.
Grover Elliott, vice president and chief financial officer of Prime Tanning Co. in Maine, told The Kansas City Star that the company bought chromium 6, but it was converted to a safer form of chromium to tan the hides.
“We can’t stress it strongly enough that chromium 6 was never used in the tanning process,” Elliott said.
However, Prime Tanning’s use of chromium 6 at its St. Joseph plant surprised the Missouri Department of Natural Resources. The department gave the tannery an exemption from water pollution regulation five years ago after the company told regulators it would prohibit several hazardous chemicals, including chromium 6, at the plant.
“Based on their application (for the exemption), we did not think they were using chrome 6,” said Susanne Medley, a DNR spokeswoman.
But for the past three years, the tannery has reported to emergency agencies that it had at least 100,000 to 1 million pounds of sodium dichromate, a compound of chromium 6, according to records obtained by the Star. Records from previous years were not immediately available.
The sludge from the plant has been spread on thousands of acres of farmland in northwest Missouri since 1983. Lawsuits filed last month claim that the sludge contained chromium 6, and linked it to brain tumors in the area.
Prime Tanning sold the plant in March to National Beef Leathers, which told the Star that it uses only the safer form of chromium – chromium 3 – in its tanning.
In an application for the exemption in 2004, the company told the DNR it would prohibit eight hazardous chemicals, including chromium 6, from the plant, according to records obtained by the Star.
“The procedure basically restricts certain kinds of substances from being used in the plant,” according to the application. The plant would “endeavor to limit” the use of those chemicals.
DNR department granted the exemption, placing regulation of the sludge under the University of Missouri fertilizer program, which does not test for hazardous chemicals.
“This determination is based upon the testing results and other information submitted to the department,” wrote Curt Gateley, a DNR environmental specialist.
The St. Joseph plant was the last one in the country to convert chromium 6 to chromium 3, a tannery expert said. Most other plants now buy chromium 3 from suppliers.
Nicholas J. Cory, director of the Leather Research Laboratory at the University of Cincinnati, said converting chromium 6 to chromium 3 is a simple process, but other experts contend the process doesn’t always completely convert chromium 6.
Many tanneries quit using chromium 6 by the end of the 1990s because of the environmental hazards. Others have closed or moved their operations overseas, where chromium pollution has become a big problem.
Elliott said the St. Joseph plant continued to buy chromium 6 and convert it to chromium 3 because it had the equipment and capacity to do the conversion.
“Chrome 6 was converted on a batch-by-batch basis to the benign chrome 3 in a separate process – before the tanning process began,” Elliott said. “We were diligent in testing each and every batch of chrome 3 to ensure that proper conversion to chrome 3 took place.”
The conversion process doesn’t guarantee that all chromium 6 will become chromium 3, said Michael Baldwin, an associate professor in the chemistry department at the University of Cincinnati, the location of the Leather Research Laboratory.
George Baggett, a Kansas City environmental consultant who has sold lime to tanneries for the conversion process, said if an inadequate amount of reducing agents is used, an incomplete reaction could leave chromium 6 in the sludge.
Investigators for the law firms that filed the recent cancer lawsuit took samples of the tannery sludge and said in the lawsuit that the results showed dangerous levels of chromium 6.
Information from: The Kansas City Star, www.kcstar.com