1.   Drug experts suspect that the use of a substance such as alcohol to manipulate a drug sample is an attempt to mask the use of performance-enhancing drugs.

2.   Garzelli, for example, was thrown out after traces of a banned diuretic, which can be used to mask steroid use, were found in his urine.

3.   Some athletes are whispered to be rubbing a cream on their skin that can mask drug use.

4.   Diuretics can also be used to mask the use of other drugs.

5.   FINA has decided to upgrade diuretics to the same status as a steroid because of its ability to mask the use of the harder drugs.

6.   Four other Chinese swimmers got two-year suspensions for using a banned diuretic, which can be used to mask steroid use.

7.   Four Chinese swimmers tested positive for a banned diuretic, which can be used to mask the use of steroids.

8.   Four Chinese swimmers tested positive for a diuretic which can mask the use of steroids.

9.   Four Chinese swimmers tested positive for a banned diuretic, which can be used to mask the use of steroids, at the world championships.

10.   Such testing is considered ineffective because athletes know when to expect screening and can stop or mask drug use in time to beat the testers.