A year after a lead paint scandal rocked New York City’s public housing system, Mayor Bill de Blasio has touted his administration’s efforts to eliminate childhood lead exposure. But a new report details how outdated city health standards led to a lack of inspections at thousands of private apartments where more than 11,000 children tested for elevated levels of lead in their blood.

The findings were released in a 28-page report by Comptroller Scott Stringer, which examines city data from 2013 through late 2018. The report alleges that the city’s Department of Health and Mental Hygiene was aware of 11,972 children who tested for blood-lead levels beyond the limit that the Centers for Disease Control says should trigger an inspection.

Department officials had gathered the children’s home addresses, but that information was not shared with the Department of Housing Preservation and Development. This means 9,671 buildings where children faced potential lead exposure were not inspected, according to the report.

“Any lead poisoning of our children must be treated as a five-alarm fire, but the city isn’t utilizing basic tools at its disposal to extinguish the fires—even in the most problematic buildings it knows about,” Stringer said in a statement.

At the time, the city had not adopted a new, stricter CDC standard for taking actions to remedy blood lead levels with five micrograms of lead per deciliter of blood. Exposure to lead can cause damage to the brain and nervous system, among many other side effects, according to the CDC.

For children who test at or above that level, the CDC urges an “environmental assessment” to identify sources of lead exposure, and when those blood-lead levels reach 10 to 19 micrograms CDC says an investigation that includes a home visit is warranted.

City health department environmental investigations were initiated at levels of 15 micrograms and above, which may have left a wide swath of childhood lead exposure cases uninvestigated by the city, the comptroller’s report states. In 2018, Mayor Bill de Blasio announced that the health department would reduce that threshold to the CDC’s five-microgram standard for private apartments.

City Hall spokesperson Jane Meyer stressed that as part of the city’s LeadFreeNYC initiative the city has already closed these gaps, and have since been inspecting apartments and engaging any families with a child who has elevated blood-lead levels.

“We wanted to get as aggressive as possible on these policies. That’s why we changed these policies,” Meyer says.

The issue that Stringer’s report raises is eerily similar to a lapse at the New York City Housing Authority, where CDC standards were not followed and inspections were not triggered for NYCHA apartments where more than 1,000 children were found to have had elevated blood-lead levels between 2012 and 2017.

The de Blasio administration continues to deal with the fallout from that NYCHA lead paint scandal, which led to federal prosecutors bringing a lawsuit against the city, arguing that for years NYCHA officials lied about performing required inspections and hid true conditions from federal inspectors.

In January, the city settled that lawsuit after de Blasio agreed to a deal that put the agency under the thumb of a federal monitor. Then-chair and CEO of NYCHA, Shola Olatoye, was forced out and the city is in the midst of spending $88 million on lead testing in 135,000 public housing apartments by 2020.