City Comptroller Scott Stringer and other critics blasted Mayor de Blasio on Friday for what they called his sloth-like reaction to the comptroller’s audit that exposed how Big Apple agencies failed to protect 12,000 children from toxic lead.

“In response to our report, City Hall officials have vaguely affirmed that they’ve begun the process of inspecting buildings associated with high levels of lead exposure, but to date no real details have been provided,” Stringer wrote the mayor in a scathing letter, which was obtained exclusively by The Post.

Stringer’s audit, released Thursday, found that the Health Department didn’t alert the city’s tenant watchdog — the Department of Housing Preservation and Development — that 11,972 children tested positive for dangerous lead levels between 2013 and 2018.

On WNYC radio Friday morning, de Blasio said he hadn’t bothered to find out “all the details” of the audit — nearly 24 hours after its publication.

Stringer called de Blasio’s response since its release “unacceptable, given the grave risk that lead paint poses to children.

“City agencies have all the information they need today to proactively inspect all buildings associated with documented instances of lead exposure, and they should do so without delay,” he writes.

The comptroller demanded a list of lead-paint inspections, remediation efforts and enforcement measures by Oct. 4.

Matthew Chachère, a lawyer with the non-profit Northern Manhattan Development Corporation who had to sue to get the city to enforce its own rules about lead paint, called de Blasio’s reaction to the audit “totally bizarre.

“How could you close your eyes to that?” he asked about the mayor appears to shrug off the startling report.

Corey Stern, a longtime plaintiffs’ lawyer for lead-paint cases, had some harsher words for Hizzoner.

“The most profound effect the mayor has had on our city is perpetuating a culture of lead-poisoned kids who will forever be damaged,” Stern said.

Bronx City Councilman Ritchie Torres said the mayor’s response to the audit echoes Hizzoner’s mishandling of the lead paint crisis at the New York City Housing Authority where officials covered up years of failure to comply with federally required lead checks.

“The lead scandal at DOH is NYCHA 2.0,” Torres said. “Instead of learning from history, the de Blasio administration seems doomed to repeat it.”

City Hall spokeswoman Jane Meyer said, “We are doing more than ever to keep kids safe — now, we are taking it a step further and inspecting additional private homes where children 6 and under live to prevent lead paint exposure.” She added that City Hall is doing an analysis to respond to Stringer’s letter that’s expected to be completed next week.