Parents are suing the Environmental Protection Agency for taking seven years to update its standards on lead paint regulations. The suit argues hundreds of thousands of families are uninformed about possible lead paint exposure in their homes.

The “unreasonably delay” lawsuit was filed Wednesday in the US Court of Appeals for the Ninth Circuit.

The suit, brought by California Communities Against Toxics, the Sierra Club, New Jersey Citizen Action and United Parents Against Lead National among others, seeks the court to require “the Environmental Protection Agency to promulgate a rule updating the dust-lead hazard standards and the definition of lead-based paint under the Toxic Substances Control Act,” and to do so “within 90 days and to finalize the rule within six months.”

“The Flint crisis put the danger of lead poisoning in the national spotlight,” said Earthjustice attorney Hannah Chang, who filed the suit, in a statement. “These organizations want people to know that lead exposure is irreversibly damaging people’s health in communities all over the country and they want the EPA to do its jobs to protect children from harm. The most common cause of lead poisoning in children in this country is the ingestion of lead dust from old house paint.”

In 2009, the EPA granted a citizens’ petition requesting a rulemaking to update the standards and then initiate proceedings, according to the complaint.

“Seven years later, the agency has yet to issue a rule, leaving hundreds of thousands of families across the country uniformed and exposed to the leaded dust and paint that may be present in their homes,” stated the complaint.

Children under the age of six are particularly vulnerable to neurological damage from lead, because they’re growing rapidly. Lead poisoning can cause severe physical and mental impairment and death, according to the Mayo Clinic.

“At the age of three, my youngest son was diagnosed with lead poisoning. He had a shockingly high lead level of 89 in his blood from the lead dust on surfaces throughout our home,” said Virginia mother Shate Cummings. “My son now faces challenges like speech impairment that he working with a speech therapist to overcome. His doctor says that we’ll begin to see the full effects of his lead poisoning when he’s five or six years old.”

Housing stock constructed before 1980 contains more than 3 million tons of lead in the form of lead-based paint, with most homes constructed before 1950 containing substantial amounts of lead-based paint.

“In Los Angeles County we know that 99 percent of cases of lead-poisoned children are from old housing and the surrounding contaminated soil,” said Linde Kite, executive director of the Healthy Homes Collaborative, one of the plaintiffs in the suit. “Revising the dust standards is a critical step in primary prevention and will tackle this problem efficiently.”

Communities of color and low-income families are more at risk of lead exposure and poisoning, according to the Centers for Disease Control and Prevention. The CDC also says there is no safe level of lead exposure for children.

In May, the community of East Chicago, Indiana, found out the EPA discovered dangerous levels of lead contamination, left over from industrial plants that closed years ago, in soil around a public housing complex and an elementary school back in 2009. The agency did not notify residents of the dangers until May of this year.

Plaintiffs argue the federal court has compelled action on other matters when public health is at risk.