SAFETY-KLEEN &lt;SK> TO BUY MCKESSON &lt;MCK> UNIT

  Safety-Kleen Corp said it agreed in
  principle to acquire McKesson Envirosystems Co, a subsidiary of
  McKesson Corp.
      It said McKesson Envirosystems' current annual gross
  revenues are about 14 mln dlrs.
      The company collects flammable solvents from its industrial
  customers for a fee, after which it analyzes and processes the
  solvents before they are burned.
  

