81.   However, as the rates of asthma and some cancers grow, researchers look at the proliferation of toxic chemicals as possible causes.

82.   However, information released Monday appeared to rule out some possible causes, including running out of fuel.

83.   I had not thought of ear irritation as a possible cause of cough.

84.   If the problem is persistent, one would be wise to check out some possible underlying causes.

85.   If it confirmed the excess brain cancer risk, further study would be required to determine a possible cause, he said.

86.   Impotence has a host of possible causes, including high blood pressure, diabetes and prostate cancer, and many of the medications used to treat them.

87.   Increased depredation by a burgeoning seal populations was one possible cause, changes in ocean temperature another.

88.   In their search, they focused on the butcher shops after discarding a host of other possible causes including cattle feed, water supply, dentistry and body piercing.

89.   Investigators have cast doubt on some possible causes of rudder failure.