Professor who first confirmed the contamination said sampling found lead levels are steadily declining and municipal water can be used for personal cleanliness

Municipal water in Flint, Michigan, has improved significantly and is suitable for personal cleanliness uses, scientists said on Tuesday in an attempt to calm fears raised by actor Mark Ruffalo and others who have questioned the safety of the supply that flows into the city’s bathtubs and showers.

Marc Edwards, a Virginia Tech engineering professor whose testing last summer confirmed the lead contamination of Flint’s water, said sampling in recent months has found that lead levels are steadily declining, although they remain too high for people to drink from the tap without a filter. Also trending downward are bacteria that can cause legionnaires’ disease, while byproducts from disinfectant chemicals are at normal levels, he and other specialists said.

Mark Ruffalo calls Flint's water crisis a 'national emergency' in recent visit Read more

“We’re seeing some very, very encouraging results,” Edwards said at a news conference in Flint, adding that he was “pretty hopeful” the water would meet federal standards for lead content within the next six months.

The upbeat assessment contrasted with a grim portrayal by Ruffalo and Water Defense, an organization he founded, which said in February its testing had turned up lead and dangerous chemicals in sinks, tubs, showers and water heaters. Ruffalo, who starred in the Oscar-winning film Spotlight, has continued sounding the alarm, while Edwards has accused him of fearmongering based on flawed testing that has frightened some people into forgoing basic hygiene.

“Many parents were deciding not to allow their children to take baths or shower or even wash their hands, they were so afraid,” Edwards said in a phone interview.

In a statement to the Associated Press, Ruffalo said Water Defense has never advised against bathing or showering in Flint but believes more testing and “a proper epidemiological study” are needed before any conclusions can be drawn.

The struggling city of nearly 100,000 has been dealing with poor water quality since switching from the Detroit system, which draws from Lake Huron, to the Flint river in April 2014 as a short-term measure to save money while another pipeline to the lake was under construction.

Residents quickly complained of bad tastes, odors and colors. E coli bacteria hit unsafe levels. And last September, state officials acknowledged a failure to add chemicals to limit corrosion had enabled the river water to scrape lead from ageing pipes, exposing people in some homes and schools to the potent neurotoxin.

Flint was under state management at the time, leading to an apology from Governor Rick Snyder. Flint returned to the Detroit system in October 2015. Criminal charges have been filed against two state department of environmental quality officials, while Flint’s utilities administrator pleaded no contest to willful neglect of duty, a misdemeanor.

Edwards was hired by the city in January to oversee water testing, his work funded through private donations.

Despite his sharp criticism of state and federal agencies’ performance, he said on Tuesday the situation had improved, with phosphate treatments coating pipes and residents heeding pleas to flush more water through the system, washing away lead-tainted rust.

Sampling of water in large and small buildings showed a decline in legionella bacteria readings from October to March, said Amy Pruden, another Virginia Tech professor.

In addition to lead, Water Defense has warned of byproducts generated by use of chlorine to disinfect water, which in high concentrations can be unhealthy. The group says they might be inhaled with steam or absorbed through the skin during showers.

Edwards and two other specialists – David Reckhow of the University of Massachusetts and Shawn McElmurry of Wayne State University in Detroit – said their analyses had shown that levels of disinfectant byproducts in Flint water were typical of those in other cities.

Edwards acknowledged many in Flint “have been through hell” and are understandably distrustful of authority, particularly those suffering from skin rashes and other symptoms they blame on the water.

But he said residents should question the credibility of Ruffalo’s group.

“They’re not scientists, nor are they familiar with how to sample water,” Edwards told the AP.