Last week, New York City Comptroller Scott Stringer revealed that he had only received 141 of more than 500 contracts for universal pre-K service providers. That, according to Stringer, is preventing his office from undergoing a “complete, independent review and registration” of more than 70 percent of universal pre-K contracts in advance of the first day of school this week.

In response, New York City Mayor Bill de Blasio has accused Stringer of “fearmongering” and assured parents that universal pre-K is ready to go.

According to the comptroller’s office, the contracts that have been reviewed have uncovered problems that Stringer said could directly affect the safety of New York City children. Among these problems? A vendor that had a former employee who was once charged with conspiracy to distribute child pornography as well as a vendor that accumulated six violations for failing to have required personnel screened with the New York State Central Register of Child Abuse and Mistreatment.

Under the city charter, the comptroller’s office has 30 days to conduct integrity reviews on all contracts for corruption, fraud and fair contract practices. In addition, many contracts received to date have included other errors, such as missing permits, inconsistent counts of students on multiple documents and vendors not listed on the charities website as being up-to-date with filing requirements.

“My office will continue to work expeditiously to review and register contracts as we receive them, in accordance with our charter-mandated responsibility,” said Stringer in a statement. “Universal pre-K holds the promise of transforming our city’s educational process, which is why we have to get it right. But we cannot sacrifice safety in the name of expediency.”