Water utilities serving American cities use tests that downplay contamination

Water utilities serving American cities use tests that downplay contamination | Environment | The Guardian:
Guardian analysis reveals millions of customers were asked to used testing method condemned by the EPA which may flush out detectable lead content
Water utilities in some of the largest cities in the US that collectively serve some 12 million people have used tests that downplay the amount of lead contamination found in drinking water for more than a decade, a Guardian analysis of testing protocols reveals.
In the tests, utilities ask customers who sample their home’s water for lead to remove the faucet’s aerator screen and to flush lines hours before tests, potentially flushing out detectable lead contamination.
The distorted tests, condemned by the Environmental Protection Agency, have taken place in cities including Chicago, New Orleans, Philadelphia and Columbus, Ohio.
The improper screening could decrease the chance of detecting potentially dangerous levels of lead in water, the EPA has said.
The analysis comes on the heels of an EPA letter, which repeated earlier warnings to utilities not to use such methods, and Guardian reporting that revealed water customers in “every major US city east of the Mississippi” could be drinking water tested using questionable methods.
...It was in 2006 that the EPA first issued guidance advising against test practices that scientists call deceptive, including removing aerators, pre-flushing lines and using small-necked bottles to collect samples.
That year, the agency said removing aerators could result in improperly lowering lead in water samples..."