ARLINGTON — Although only one Arlington business seems to have been hit so far, several businesses in downtown Arlington were abuzz after the Arlington Pharmacy at 540 N. West Ave. discovered on Feb. 2 that they’d been handed a counterfeit $20 bill.

Mary Anderson, office manager of the Arlington Pharmacy, made sure to circulate the word to her fellow downtown Arlington businesses after the pharmacy’s bank called them to notify them of the counterfeit bill, although none of the other businesses reported receiving any counterfeit bills.

“We could have received it at any time on Feb. 1, since we always deposit our earnings the next day,” Anderson said. “We check internally for the larger bills, but not normally for the $20 bills. Of course, now we’re going over all the $20 bills we receive with the special light-pens.”

The counterfeit $20 bill was paid at the pharmacy’s coffee shop, just as a previous counterfeit $20 bill had been paid to the coffee shop in the spring of last year.

“It was a little less than a year ago, and at the time, I thought it was a fluke,” said Anderson, whose fellow pharmacy employees use counterfeit bill detector pens purchased from Office Depot. “Part of the problem with counterfeit bills is that you can’t know for sure if the customers who hand them to you are the ones who made them. One of our regular, most trusted customers just wound up with a counterfeit bill once.”

The redesigned $20 bill was issued in 2003 with a security thread, a portrait watermark and a color-shifting numeral “20.” According to Anderson, the differences between authentic and counterfeit $20 bills can be spotted if they’re placed side-by-side, but on its own, a counterfeit $20 bill can be difficult to distinguish from the real thing.