As promised, local activists determined to eliminate chloramine from the tap water were granted a meeting with federal Environmental Protection Agency representatives earlier this month to plead their case.

How far they got, however, is questionable.

Citizens Concerned About Chloramine met with the EPA on Sept. 5 after Congresswoman Anna Eshoo's office arranged the meeting. Eshoo had issued a statement saying she was concerned about reports of terrible allergic reactions to chloramine, a disinfectant which replaced chlorine in Peninsula tap water in 2004.

Despite those anecdotal reports, Bruce Macler of the federal EPA's San Francisco office defended the switch to chloramine, both at the meeting and to the Voice. Procedurally, he said, reports of bad reactions to chloramine must be recognized by the Centers for Disease Control or the medical community before the EPA can take action.

A few days after those remarks, Macler said CDC representatives were heading to Vermont to investigate numerous complaints there about chloraminated tap water.

"As far as we know there is no evidence there is a problem with public health," Macler told the Voice last week. "When we talk about what's safe, we talk about generally safe. It is possible people are affected. Medical folks have to start saying this is an issue."

Macler's position angered CCAC president and Menlo Park resident Denise Johnson-Kula, who says she almost died from a respiratory reaction while taking a shower immediately after the switch in 2004. She continues to have respiratory reactions anywhere near tap water vapors, as does at least one Mountain View resident. She believes there could have been others who weren't as fortunate.

"I could have died," Johnson-Kula said. "The autopsy would have said 'Acute respiratory distress, cause unknown.' Who would have known?"

Johnson-Kula's group says at least 400 Bay Area residents, including several in Mountain View, have developed skin rashes, respiratory problems or inflamed digestive tracts after the switch to chloramine. That switch, made by the San Francisco Public Utilities Commission, which manages the Peninsula's Hetch Hetchy water, was originally made at the EPA's behest.

The EPA had recommended that water agencies switch to chloramine to reduce trihalomethanes, a carcinogenic byproduct of chlorine disinfection. At high levels, chloramine is classified as a dangerous chemical that can cause gastrointestinal and respiratory problems. The EPA has regulated it at no more than four milligrams per liter in tap water, the same limit as chlorine.

However, the byproducts of chloramine are "much more toxic" than chlorine's, according to Dr. Michael Plewa, professor of genetics at the University of Illinois, who recently co-authored a study on tap water disinfection byproducts.

In the study, hamster ovary cells were used to examine the effects of one kind of unregulated disinfection byproduct -- haloacetonitriles -- which may have increased with chloramine use. (Currently, only 11 of over 600 byproducts known to the EPA are regulated.)

Because Plewa's study does not involve a whole animal, the EPA is hesitant to use it in the case against chloramine, Macler said. He also said Plewa's research may not apply to the conditions in the Bay Area and that the byproducts may not be present here.

Plewa isn't as hesitant, and has said the byproducts he is studying are the most toxic he has ever seen. In an e-mail to the Voice last month, he recommended a switch back to chlorine.

Critics of chloramine still claim it has done little, if anything, to improve the water. Macler said one positive result of the switch to chloramine was reduced levels of legionella, but Johnson-Kula said legionella was never really a problem in local tap water.

Johnson-Kula has joined Ellen Powell, of People Concerned About Chloramine in Vermont, to call for government oversight of the EPA's actions pertaining to chloramine. She is also meeting with Bay Area congressmen Mike Honda and Pete Stark in the next few weeks.

Macler said the EPA is in the middle of a six-year update to regulations of disinfection byproducts, and that it would probably continue research of chloramine disinfection byproducts on whole animals.

As for the CDC's trip to Vermont. "We'll hear back in a few weeks, we'll find out if they want to pursue anything," he said.

The Vermont state legislature spent two days hearing testimony on the issue earlier this year.

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