Politics & Government

Slime-killing pesticide worried DHEC, but agency didn’t keep it out of drinking water

South Carolina regulators raised questions seven years ago about an unapproved chemical in Denmark’s drinking water but did not force the city to quit injecting the slime-killing pesticide into a public well, according to state enforcement records.

Instead, the S.C. Department of Health and Environmental Control fined Denmark $3,000 for an array of drinking water violations that included questionable oversight of HaloSan, a product that can be harmful to people if not administered in the proper doses, records show.

Only this year, after regulators at Clemson University learned about HaloSan, were the injections halted because the chemical did not have federal approval. HaloSan has rarely, if ever, been used in drinking water systems across the country, records show.

Former state Rep. Bakari Sellers, a lawyer who has sued the city on behalf of Denmark residents, said DHEC and the city have plenty of questions to answer about Halosan injections in drinking water.

“For many of us, it looks like the city and DHEC are hiding more than they are telling,’’ said Sellers, a CNN commentator who grew up in the city of 3,300.

For 10 years, the city pumped HaloSan into a municipal well to kill iron slime, even though the EPA had not approved the product for use. Few people were aware of the injections.

Ingredients in Halosan can irritate people’s skin and eyes if not used properly in drinking water. A key question is whether anyone got sick, say attorneys who have filed two lawsuits against the city over the HaloSan injections.

“Imagine being a citizen in Denmark and you are not sure how this would affect your health,’’ said Sellers, who met with Denmark residents Monday to discuss the issue.

DHEC officials said last week that the chemical is safe and no one became ill from exposure to HaloSan, which had been certified for use by a national organization that examines chemicals in drinking water. Because NSF International had said HaloSan was safe, DHEC told Denmark officials in 2008 they could use the material, the department has said.

But agency enforcement records show that Denmark water treatment operators were ‘”unfamiliar with the function’’ of the HaloSan system.

The HaloSan system was supposed to register how frequently injections were occurring in the water, but that was not documented, according to a Sept. 30, 2011, DHEC memorandum obtained by The State. Critics, including one nationally known researcher, have said it’s unclear how much HaloSan was injected over the years.

After DHEC raised those concerns, Denmark brought in HaloSan’s manufacturer to train staff “to increase operational skills with the iron bacterial removal system,’’ according to a Nov. 15, 2011, letter to DHEC from Denmark administrator Heyward Robinson.

Records show that DHEC’s concerns in 2011 were mollified after training was held, according to a 2012 DHEC inspection report of the Denmark waterworks. The agency gave Denmark a satisfactory rating for the HaloSan system in 2012.

DHEC Spokesman Tommy Crosby said Wednesday that his agency did not force Denmark to stop using HaloSan because the city corrected the problem. Crosby said the Denmark system of injecting HaloSan was automated, rather than manual, so there was “no immediate threat’’ to drinking water, Crosby said.

As a result, there was “no need to stop the use of the treatment system,’’ Crosby said.

Denmark Mayor Gerald Wright was not immediately available for comment but he said earlier this week that the city has tried to comply with all requirements from DHEC through the years when questions came up. He said he remembers DHEC recommending HaloSan to Denmark. DHEC officials have said they don’t recall who recommended HaloSan.

“When things are pointed out to us that we need to change, we expeditiously change it,’’ Wright said. “It’s in our best interests.’’

Efforts to reach representatives of Berry Systems of Lugoff, HaloSan’s manufacturer, were unsuccessful. The company’s website said HaloSan provides “the most effective method to clean a well.’’ The website said HaloSan helps clear up clogs in wells that produce odors, discolored water and staining.

State officials say HaloSan was used to eliminate an iron bacteria found in one of the city’s water supply wells. The bacteria can build up, create a slime and keep groundwater from being siphoned into the well for dispersal to city residents.

HaloSan contains the chemical ingredient 1-bromo-3-chlorodimethylhydantoin, or BCDMH, which is used in other products with different names. HaloSan and other trade names, including Dantoin, were certified for use in drinking water and for cleaning wells, according to NSF International, a national organization that signs off on the use of such chemicals.

HaloSan has since been decertified at the manufacturer’s request, according to the NSF. The manufacturer now is using another product for the same purposes, the NSF said.

Most states require that water treatment chemicals comply with NSF International’s standards for drinking water, the organization’s Dave Purkiss said in statements emailed to The State newspaper. But HaloSan is a pesticide that also needs EPA approval for use in drinking water systems. Clemson has been designated by the EPA to regulate the pesticide program.

Researchers from Virginia Tech and the University of South Carolina learned last spring that HaloSan was being injected into Denmark’s water and began asking questions. That’s when pesticide regulators said the chemical had not been approved by the EPA and ordered Denmark to stop injecting it into the water.

Marc Edwards, the Virginia Tech researcher who helped expose the Flint, Mich., water crisis, has said it’s difficult to tell how HaloSan might have affected anyone’s health. But he said chemicals not approved by the EPA pesticide program should not go into drinking water.