Volkswagen and BASF, two German giants, are reassessing their activities in the region, where the Chinese government has cracked down on Muslim minorities.
The F.T.C. and H.H.S. are examining the tactics of group purchasing organizations that generic industry executives say have led to scarce supplies of treatments like chemotherapy.
Attacks on two dozen ships since November are forcing shipping lines to figure out whether and when to skip the Suez Canal and send vessels on longer voyages around Africa.