DENMARK — The water in this small town near Orangeburg has become infamous in recent months because it was treated for a decade with a chemical, HaloSan, that hasn't been used in any other public drinking system.
That fact already had stirred distrust in the town and its water supply. But residents should know about other concerns hiding in their pipes, a scientist says.
Kenneth Rudo, who worked for the state of North Carolina as a toxicologist for 28 years, announced at a rally in Denmark that records he's examined from the town show many past episodes of contamination. Those include carcinogenic leachates from a dry cleaner that were present for years before the town shut down affected wells in 2006, and indications that gasoline had seeped into the water supply between 2006 and 2008.
There's no evidence those contaminants persist in the water today, Rudo said, and the town has not used HaloSan since last summer.
A spokesman for the S.C. Department of Health and Environmental Control acknowledged that dry-cleaning chemicals had been detected as early as 2002 but said readings did not reach the Environmental Protection Agency's threshold for action and the agency had never seen clear evidence of gasoline contamination.
What persisted, however, is the town's water also contains a naturally occurring metal: manganese.
The element is not uncommon in groundwater wells and, along with iron, causes the occasional water discoloration residents have reported. But the concentrations seen in Denmark on and off for at least a decade reach levels that emerging science shows could be harmful to young children's brain development, said Rudo, who has been hired by a law firm suing the town of Denmark.
"Look after your health," Rudo told a group of about 150 people at the Jan. 26 rally. "Get your doctor to look at you before something bad could happen."
Denmark residents march downtown with advocates of Flint and Virginia Tech for water crisis
North Carolina as a toxicologist Kenneth Rudo, Flint water advocates and members of Virginia Tech met for a rally to cause awareness for the town's drinking water on Saturday, Jan. 26, 2019 in Denmark.
Manganese is an essential nutrient to humans. But like many other environmental threats, its amount determines its toxicity. The metal has long been known to cause a condition similar to Parkinson's Disease in adults who inhale it in large concentrations.
In water systems in the United States, it's treated as an aesthetic concern. The EPA has a secondary standard for how much should be in the water, but it's a recommendation; water systems aren't required to regularly monitor for manganese.
In the past decade, however, researchers have begun to link drinking water laced with the metal to developmental problems in young children. Studies tracking the average concentration of manganese in well water in North Carolina counties have shown correlations between higher levels of the metal and increased infant mortality, heart defects and neurodevelopmental defects.
One study in Canada, published in 2011, showed an even stronger connection. The study of 362 children aged 6 to 13 years old showed that children who drank water with higher manganese levels had lower IQ scores.
"It's up to the regulators to decide, 'OK, what's the magnitude of the IQ deficit we are willing to accept?'" said Maryse Bouchard of the University of Quebec at Montreal, the lead author of the study.
It was Bouchard's work that helped convince regulators in Minnesota to set a health standard for manganese, said Sarah Johnson, of the Minnesota Department of Public Health. State officials there were most concerned about children younger than a year, who are even more sensitive because they may not have developed the ability to excrete the metal yet, as older people can.
"Infants have a unique susceptibility to manganese," Johnson said.
Minnesota is largely at the forefront of regulation. Rules on manganese are still under development in Canada, Bouchard said. Many states, including South Carolina, do not have any standards in place beyond the EPA's recommendation, even though concentrations well above Bourchard's recommended limit of .1 miligrams per liter have been found in wells in the piedmont region.
The state is now collecting data on the metal as the EPA monitors manganese across the country, said Tommy Crosby, a spokesman for DHEC. That data may form the basis for future rules on manganese.
A history of infractions
Other contaminants found so far by Rudo's review of Denmark's own water sampling largely tell the story of a water system that has been beleaguered for years.
Attorneys representing Denmark in two class-action lawsuits are not speaking about the town's water system, a receptionist at the law firm Ness & Jett LLC said. Denmark Mayor Gerald Wright previously directed The Post and Courier to speak with those attorneys. Wright also has said repeatedly the city's water is safe to drink.
Chlorinated solvents, a cleaning chemicals that are known human carcinogens, were in the town's water for years before a contaminated well was taken offline in 2006, Rudo said. The compound is so dangerous in part because even one molecule can change human DNA, starting off the cancer process.
Crosby said the amounts of the chemical did not meet EPA's standards for action until 2006. But the EPA's standard is not solely based on health effects: The agency's health-based rules for chlorinated solvents say there should be none in the water at all.
Either way, the episode sparked an emergency hookup to nearby Bamberg's water supply that lasted for two years.
By 2010, the town entered a consent order with DHEC because of complaints of discolored water and because it did not have basic system maintenance procedures. A year later, DHEC found that the town still had not fixed some of the maintenance deficiencies. It wasn't until 2013 that the dropped the orders.
But during both censures, the town was still using HaloSan — a chemical that wouldn't spark a flurry of renewed attention and public mistrust of its water until 10 years later.