Bossier City and Louisiana state officials said last week that chlorine levels in the city's water will remain safe.
Erin Brockovich, the famed legal clerk-turned-environmental activist, claimed in a social media post last week that Bossier City officials were not telling the truth about the safety of the city's water.
Brockovich made her claim Oct. 10 after Bossier City officials announced that the city would flush its water system with chlorine as a precautionary measure after a nearby water system tested positive for the brain-eating amoeba.
State officials confirmed later that day that the water system tested positive for the brain-eating amoeba and that the flush was underway.
In the post, Brockovich claimed that the chlorine-flushed water would be dangerous for residents to drink and bathe in.
The state's health officer and Bossier City officials maintain that the water is safe and that the slight increase in chlorine levels is well within proper guidelines.
Brockovich is best known for legal work in California in the 1990s. Her efforts inspired the 2000 film "Erin Brockovich" starring Julia Roberts. Brockovich regularly posts on social media about drinking water systems and water resources across the country.
"You are going to be burned out and flushed ... because the City won't get off chloramine and clean the dirt out of your drinking water like they are supposed to," she said of Bossier City's chlorine flush. "And the line about the 'Water Still Safe to Drink' is a ridiculous LIE !!!"
Brockovich said one result of chlorine flushing is an elevated level of trihalomethanes, chemicals formed in drinking water primarily as a result of the coloration of organic material in the water supply.
Brockovich said the chemicals are toxic.
"You can actually inhale more than you could possibly ever drink," she wrote. "These toxic volatile chemical compounds will linger in your homes as indoor air pollution."
The U.S. Centers for Disease Control and Prevention reports that chlorine protects against waterborne diseases and small amounts are not harmful to health.
Bossier City began flushing chlorine through its water system on Oct. 10 after one of five samples of city water tested positive for Naegleria fowleri, the brain-eating amoeba. The flush is to last about 60 days.
In 2017, the World Health Organization wrote about trihalomethanes in a section of its "Guidelines For Drinking-water Quality." The chemicals are bromoform, bromodichloromethane, chloroform and dibromochloromethane. Of the four, chloroform is the most common, the WHO wrote.
The state department of health records and analyzes trihalomethane levels for water systems statewide.
Long-term health effects of exposure to trihalomethanes in the water could include liver, kidney or central nervous system problems and increased risk of cancer, said the Louisiana Department of Health.
Only two of the four trihalomethanes — bromodichloromethane and chloroform — are considered potential human cancer-causing agents, the World Health Organization reports.
During the 60-day flush, Bossier City will switch to free chlorine, which is a stronger and faster-acting disinfectant than the substance it normally uses. That substance is chloramine, a combination of chlorine and ammonia.
Sligo Water Systems, which serves a portion of southern Bossier Parish, tested positive for the amoeba in late September.
Country Place Subdivision, the Town of Benton and the Cypress Black Bayou Water Systems also are undergoing the chlorine flush because those entities buy water from Bossier City.
Dr. Jimmy Guidry, the state health officer, said the chlorine levels during the flushes will rise temporarily from .5 milligrams per liter to 1 milligram per liter, which he said is well within best practices and standards.
Those levels aren't close to the chlorine levels of water you'd swallow in swimming pools, he said.
"There are many water systems in the country that actually (and) routinely have chlorine at 1 milligram to treat their water," he said. "We use it occasionally when we find the amoeba, but it's a perfectly safe level."
Some residents may notice a chlorine taste or odor in drinking water as a result of the chlorine burn. Medical facilities, aquatic pet owners, dialysis centers and others who take special precautions to remove chlorine should continue to take the same precautions, according to the health department.
"I'm absolutely sure about my science," Guidry said of the chlorine levels.