houston suspicious substance find houston campaign headquarter u.s. republican presidential contender senator ted cruz non-toxic local media report say cite cruz campaign official houston fire department say send hazardous materials team investigate substance houston chronicle cite source scene say office receive powder-filled envelope fbi hazmat team city houston fire department come scene test substance find non-toxic take away fbi test catherine frazier cruz campaign quote say houston chronicle houston fire officials immediately available comment report jon herskovitz austin houston bureau edit peter cooney sandra male article fund part sap independently create reuters editorial staff sap editorial involvement creation production suspicious substance cruz 's houston headquarter non-toxic