Both players have been carrying knee injuries. White is recovering from a ligament problem, while Smith has suffered several knocks in the professional American league.
"I'll be playing through a slight problem but I'm not too worried about it," admitted former Arsenal star Smith, who now players for Boston Breakers.
Powell said: "Faye and Kelly have come back from horrific injuries but they've both done well in the build-up to the tournament and we'll manage them accordingly."
If Arsenal central defender White does not make the starting line-up then Everton's Lindsay Johnson will take her place and the captain's armband will be worn by either Smith or Everton midfielder Fara Williams.
England squad: Brown (Everton), Chamberlain (Chelsea), Bardsley (New York Sky Blue), A. Scott (Boston Breakers), Stoney (Chelsea), Johnson (Everton), Asante (New York Sky Blue), White (Arsenal), Unitt (Everton), Bassett (Arsenal), Williams (Everton), Carney (Chicago Red Stars), Chapman (Arsenal), J. Scott (Everton), S. Smith (Leeds Carnegie), Westwood (Everton), Buet (Chelsea), Clarke (Leeds Carnegie), K. Smith (Boston Breakers), Aluko (St Louis Athletica), Handley (Everton), Sanderson (Chelsea).
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