Cook County officials say a finance director is out of a job after overstating county tax revenue by about $90 million.

County Board President Toni Preckwinkle’s office made the disclosure Friday after discovering the error in May. The former worker, Faisal Abbasi, 36, of Prospect Heights, accidentally made double entries for county cigarette and sales tax revenue from 2009, said Cook County Chief Financial Officer Tariq Malhance.

“It was really a human error that one person booked it, and then, not realizing that it had been booked before … he [duplicated it], and booked again,” Malhance said.

But Abbasi, who was laid off from his county job when the Preckwinkle administration took office in February, said he is simply a scapegoat for the mistake. The idea that he alone could have caused such an error is “a bunch of hogwash and smoke and mirrors,” Abbasi said.

“You can’t just put in a $20 million or $30 million dollar entry without the external auditors looking at it.,” he told WBEZ on Friday. He acknowledged he may have made the mistake, but said it is possible that another worker could have used his computer account to enter revenue into the county’s accounting system.

Malhance said the mistake will not affect the budget because the county allocates money based on projections, not on revenue as it comes in. He said he does not think the mishap will affect the county’s rating with bond agencies.