The ICC concluded that there was "no compelling evidence" to suspect anyone of wrongdoing in the third one-day international between England and Pakistan.
Afridi called Pakistan's scandal-marred tour of England the "most difficult" of his career as the team staged a low-key return after four gruelling months away.
Pakistan cricket was embroiled in another controversy after Shoaib Akhtar was caught on camera tampering with the ball during the final ODI against England.
England completed a clean sweep of their 2010 home series when they defeated Pakistan by 121 runs in the fifth and final one-day international.
Four Pakistan players including captain Shahid Afridi, Shoaib Akhtar, Kamran Akmal and Mohammed Yousuf, currently touring England have cleared their respective dope tests conducted by the WADA.
Pakistan's scandal-filled tour of England reaches its conclusion at the Rose Bowl on Wednesday with the deciding match of a closely fought one-day series.
Pakistan team manager Yawar Saeed has confirmed that fast bowler Shoaib Akhtar is fit to participate in Wednesday's fifth ODI against England at Rose Bowl in Hampshire.
Pakistan recovered from a terrible start to their day to complete a spirited victory in the fourth one-day international against England at Lord's.
Pakistan won the toss and opted to bat first in the fourth ODI against England, which has been tarnished by further spot-fixing allegations against the tourists.
A victory for England will see them get their hands on the ODI series trophy in addition to the test and the T20 trophies, whereas a win for Pakistan will get them to draw level with England at 2-2.