LAUSANNE, Switzerland (AP) -- Swimming governing body FINA says all 362 doping tests from last month's world championships in Shanghai have come back negative.
There were 311 urine samples taken, including 43 screenings for the blood booster EPO, and 51 blood tests.
FINA announced in Shanghai that the blood tests taken there would go toward the implementation of a biological passport program, much like the one the UCI installed in cycling.
Brazilian sprinter Cesar Cielo won two gold medals at worlds after being cleared of doping by the Court of Arbitration for Sport.
FINA had challenged a Brazilian federation decision to give Cielo only a warning after he tested positive for furosemide, a banned diuretic and masking agent, at a meet in Rio de Janeiro in May.