Michigan has amended its water testing rules in the wake of the Flint poisoning crisis, the Guardian can reveal, as a lawsuit filed by Flint residents and advocacy groups sought to compel city and state officials to follow federal requirements for testing and treating water for lead content.

Until recently, both the city of Flint and guidelines issued for the entire state by the Michigan department of environmental quality (MDEQ) required that residents turned on their faucets for several minutes before taking a sample of water for lead testing.

This practice of “pre-flushing” taps is thought to lower lead content in samples and is discouraged by the Environmental Protection Agency, despite its widespread use across the U.S.

Flint belatedly removed pre-flushing from its tests in December and now it has emerged MDEQ has followed suit, following consultation with the EPA, which recently issued an emergency order to intervene in the Flint crisis. Previously, Michigan residents were told to “turn on the cold faucet of your kitchen or main bathroom sink and let it run for three to four minutes” the night before the test.

An MDEQ spokeswoman told the Guardian that the previous testing instructions were “in compliance” with the EPA’s lead and copper rule, which doesn’t explicitly ban pre-flushing or several other alterations used by cities and states to influence lead content.

“The situation in Flint has taught us that technical compliance may not be enough,” she said. “The DEQ has been working in concert with the EPA to take a look at every aspect of the lead and copper rule and to see where improvements can be made.

“Once we have completed our mission in Flint, we look forward to working with the EPA to bring about formal changes in the lead and copper rule so that there is uniformity in how it is implemented nationwide.”

The change in testing conditions comes amid growing pressure on state and federal authorities to reform the 25-year-old framework that’s aimed at preventing people suffering an array of health effects from lead, which is a known neurotoxin.

Following the Guardian’s revelation that distorted water tests are commonplace in a number of U.S. cities, the head of the Ohio EPA called upon his national counterparts to overhaul the “woefully inadequate” lead and copper rule.

On Wednesday, a complaint was filed in U.S. district court by the Natural Resources Defense Council, the ACLU of Michigan, Concerned Pastors for Social Action and Flint resident Melissa Mays, who claims each member of her five-strong family has been adversely affected by lead seeping into the water supply.

The lawsuit demands that city and state officials follow EPA requirements for testing and treating water, as well as replace all lead pipes in Flint and remedy the health impacts suffered by the city’s population, 40% of whom live under the poverty line.

“The water in Flint is still not safe to drink because city and state officials are violating the federal law that protects drinking water,” said Dimple Chaudhary, senior attorney with the Natural Resources Defense Council.

“In doing so, they are exposing the people of Flint to lead, a powerful toxin that can be devastating to young children. We are asking a federal court to step in because the people of Flint simply cannot rely on the same government agencies that oversaw the destruction of its infrastructure and contamination of its water to address this crisis.”

The Flint water system asked customers to flush taps for at least five minutes, the lawsuit states, with the intention of minimizing the amount of lead in samples. Despite this, high lead levels were still found in Flint, with one household receiving water with levels of 400 parts per billion – an enormous increase on the federally mandated action level of 15 parts per billion.

Flint residents began to complain that their tap water was “discolored, laden with sediment, and foul smelling” shortly after the city switched water supply to the Flint river in April 2014, the lawsuit states. Residents also reported skin rashes, hair loss and vomiting after drinking or bathing in the water.

Despite repeated warnings from state officials and the EPA, the problems were downplayed until December last year when Flint’s Karen Weaver declared a state of emergency, followed by a similar declaration by Michigan governor Rick Snyder in January. By this point, a study by a Flint pediatrician found that the proportion of Flint children with elevated blood lead levels had doubled since the change in water source.

“I joined this lawsuit because I no longer believe the city of Flint and the state of Michigan can solve Flint’s water crisis and return safe drinking water to our homes,” said Mays.

“For years the state told us we were crazy, and that our water was safe, which wasn’t true. For the sake of my kids and the people of Flint, we need a federal court to fix Flint’s water problems because these city and state agencies failed us on their own.”

Originally published by The Guardian