Some leading brands of home water-filtration systems, bought by tens of thousands of health-conscious consumers, actually increase the amount of lead in drinking water, according to a study released Thurs-day.

The study, commissioned by a San Francisco environmental group, found that two common brands of water filters raised lead levels to three times the federal standard and to more than 60 or 70 times a more stringent state level.Four other brands were found to have lead levels above the state standard. In all, the six brands represent as much as 50 percent of the $2.5 billion market for water filtration systems, the group said.

In response to the study, one manufacturer, Franke Inc., said it was withdrawing one of its product lines from the market and offered to refund consumers the price of any recent purchases.

Franke said it will conduct its own test on the products and work with the Center for Environmental Health in San Francisco, which commissioned the study, to ensure its products meet public health requirements.

Michael Green, executive director of the center, welcomed the move and said his group's goal is to use the state's anti-toxics law, Proposition 65, to force other manufacturers to do the same.

Lead is the leading environmental threat to children's health. Even at low levels, lead has been shown to impair fetal development, cause learning disabilities in children and lead to miscarriages in pregnant women.

In all, the study looked at 16 home water filtration systems that have separate faucets mounted on a sink and usually have filters mounted below the sink. They range in cost from $100 to $300.

View Comments

Over a three-week period, the study tested daily lead levels in water that was left standing in the faucets. Many of the systems have brass faucets, which contain lead that leaches into water left in the faucet.

In some cases, the researchers found, the filtering system can increase the corrosiveness of the water and increase its ability to leach out lead.

Based on consumption of eight glasses of water a day, the study showed that a filter made by Omni contained 35.5 parts lead per billion, and one made by Franke contained 30.1 parts lead per billion - both well above the federal standard of 11 parts per billion.

Four other products, made by Amway, Equinox International Corp., QMP Inc. and Waterboss International, were below the federal level but above the Proposition 65 level of 0.5 parts per billion.

Join the Conversation
Looking for comments?
Find comments in their new home! Click the buttons at the top or within the article to view them — or use the button below for quick access.