Archives for posts with tag: Chicago

From Chicago Tribune:

Chicago’s first round of testing for a toxic metal called hexavalent chromium found that levels in local drinking water are more than 11 times higher than a health standard California adopted last month.

But it could take years before anything is done about chromium contamination in Chicago and scores of other cities, in part because industrial polluters and municipal water utilities are lobbying to block or delay the Obama administration’s move toward national regulations.

The discovery of hexavalent chromium in drinking water is renewing a debate about dozens of unregulated substances that are showing up in water supplies nationwide. Potential health threats from many of the industrial chemicals, pharmaceutical drugs and herbicides still are being studied, but researchers say there is strong evidence that years of exposure to chromium-contaminated water can cause stomach cancer.

Test results obtained by the Tribune show that treated Lake Michigan water pumped to 7 million people in Chicago and its suburbs contains up to 0.23 parts per billion of the toxic metal, well above an amount that researchers say could increase the long-term risk of cancer.

Chicago began quarterly testing for the dangerous form of chromium this year after the U.S. Environmental Protection Agency urged cities to track it while the Obama administration wraps up a scientific review — the first step toward a national standard. Until now, the results have not been shared with the public.

Federal officials are being nudged to act by California, which took a three-year look at the science and last month established the nation’s first “public health goal” to limit hexavalent chromium, an industrial pollutant made infamous by the 2000 movie “Erin Brockovich.”

The California Office of Environmental Health Hazard Assessment defines the goal, 0.02 parts per billion, as an amount that reduces the risk of developing cancer to a point considered negligible by most scientists and physicians. Studies show that exposure to the metal also increases the risk of reproductive problems, interferes with childhood development and causes liver and kidney damage.

Echoing their counterparts in other cities where the metal has been detected, Chicago officials stress that local tap water is safe and suggest that if a national limit is adopted, it likely would be less stringent than California’s goal. But the findings raise new concerns about a toxic metal that can pass unfiltered through conventional water treatment.

More.

From Chicago Tribune:

Though Chicago and other cities have long reported that lead levels in their water meet federal standards, regulators and scientists worry testing methods used for two decades could significantly underestimate consumers’ exposure to the toxic metal.

Recent test results in Chicago may back up those fears: High lead levels were found in drinking water in seven of 38 Chicago homes tested by federal regulators this spring, according to records obtained by the Tribune.

“That’s not really good news,” said Marc Edwards, an environmental engineering professor at Virginia Tech who researches lead in water. The testing suggests lead in water could be a “significant human health concern,” he said.

Environmental Protection Agency officials are still analyzing the tests, but the results give credence to concerns voiced by advocates and scientists that lead could be an underestimated health risk in the nation’s drinking water, especially in older cities and suburbs where lead pipe and solder are common.

The results also speak to concerns that utilities can “miss” lead when testing water by using certain permitted techniques, such as flushing pipes the night before samples are taken.

“People don’t really know the extent of the problem,” said Jeffrey Griffiths, a physician who is chairman of a drinking water advisory board for the EPA and a professor of public health and medicine at Tufts University School of Medicine.

Under federal law, local utilities must test water in a relatively small sample of homes. If lead concentrations exceed 15 parts per billion in more than 10 percent of water samples, the utilities must alert residents and try to lower levels. The city of Chicago hasn’t exceeded the lead limit in nearly 20 years.

The allowable amount of lead was set in the 1990s and is based on a level utilities could feasibly meet. It is not a health-based standard, and many health and environment experts think the level allowed is too high.

Experts say there is no safe level of exposure to lead, which has been known to cause diminished IQs in children, even at low levels, and heart attacks and strokes in adults.

“What you really want is zero,” Griffiths said. “Four (parts per billion) is better than 15, but four is still four.”

Water rarely contains lead when it leaves treatment plants, but the heavy metal can leach into water while it sits in or flows through service lines that connect water mains to homes. Pipes and faucets inside homes also can contain lead, as can solder and brass parts used with plumbing materials.

Lead in water doesn’t smell or taste strange, so consumers would likely be alerted to the problem only if they have their water tested or if regulators discover the problem.

To prevent leaching, treatment plants add orthophosphate and other chemicals to water. A chemical reaction causes a white coating to form on the inside of pipes that is meant to stop lead from leaching into the water, but it isn’t always effective.

Water treatment is also complicated. For orthophosphate to protect against lead, the pH of water needs to be within a certain range. But if pH is too high in some water systems, calcium can build up, making valves like those on fire hydrants hard to open.

“You are kind of doing a balancing act,” said Miguel Del Toral, regulations manager for EPA Region 5’s Groundwater and Drinking Branch. “It’s not as simple as just make one change and you are fine.”

If high lead levels persist, a utility may have to replace lead service lines, although recent studies show partial pipe replacements can actually contribute to spikes in lead levels because they disturb lead rust that breaks off or leaches at a higher rate.

In Illinois, 52 water systems have been found to have high lead levels since 2008, according to a Tribune analysis of state records. Last November, New York City alerted residents after 14 percent of samples contained elevated lead levels.

Although the majority of water systems report that homes they test meet federal regulations, some experts think those results are due to outdated testing, government agencies gaming the system, or both.

More.

From Chicago Tribune:

Trace amounts of sex hormones, prescription drugs, flame retardants and herbicides are being detected in treated drinking water pumped to more than 7 million people in Chicago and its suburbs.

In the latest round of testing prompted by a 2008 Tribune investigation, city officials discovered that more than two dozen pharmaceutical drugs and other unregulated chemicals pass through Chicago’s massive treatment plants.

Little is known about potential health effects from drinking drug-contaminated water, but scientists and regulators increasingly are concerned about long-term exposure, even at very low levels.

“We need to start addressing the cumulative effects that these low-dose exposures could be having on people,” said Thomas Burke, associate dean of the Johns Hopkins Bloomberg School of Public Health.

“There are no quick solutions,” said Burke, who chaired a National Academy of Sciences committee that called for a dramatic overhaul of the way the U.S. regulates toxic chemicals. “But we need a new approach that is more responsive to emerging science.”

Like other cities, Chicago must notify the public if its drinking water contains regulated contaminants, including lead, pesticides and harmful bacteria. There is no such requirement if pharmaceuticals and other unregulated substances are detected.

Annual water quality reports mailed last month to people in Chicago and the suburbs noted that the city is testing for substances that aren’t on the U.S. Environmental Protection Agency’s list of regulated contaminants. A list of results obtained by the Tribune is dated April 11 but wasn’t posted on the city’s website until after the newspaper asked for it last week.

City officials were prompted to start testing for the substances after the Tribune found trace amounts of pharmaceuticals, residue from personal care products and unregulated industrial chemicals in local tap water. Substances found in the city’s latest tests include the sex hormones testosterone and progesterone; gemfibrozil, a prescription cholesterol-fighting drug; and DEET, the active ingredient in bug spray.

The tests also found perfluorooctane sulfonate, an ingredient in Scotchgard stain-fighting coatings; bisphenol A, a hormone-like plastics additive; and tris (2-butoxyethyl) phosphate, a flame retardant chemical.

“Our very awareness of trace amounts of these chemicals comes in large part because we are aggressively conducting research on water quality and safety,” said Tom LaPorte, a spokesman for the Chicago Department of Water Management.

Drugs end up in drinking water after people take medicines and residue passes through their bodies down the toilet. Conventional sewage and water treatment filters out some of the substances, or at least reduces the concentrations, but studies have found that small amounts still get through.

Although treated sewage from the Chicago area drains away from Lake Michigan, more than 300 other cities discharge treated waste and untreated sewage overflows into the lake and its tributaries, according to the EPA.

More.

%d bloggers like this: