Zirbel confirms B sample is also positive

Tom Zirbel (Bissell Pro Cycling)

Tom Zirbel (Bissell Pro Cycling) (Image credit: Jonathan Devich/epicimages.us)

Just a month after he announced he had returned a non-negative test for DHEA at the 2009 USPRO TT championships, American rider Tom Zirbel has confirmed that his B-sample analysis is also positive.