In this 1998 press release the World Health Organization stated:
The results of this study, which have been completely misrepresented in recent news reports, are very much in line with the results of similar studies both in Europe and elsewhere: passive smoking causes lung cancer in non-smokers (emphasis original)
That's interesting. Considering this quote from the actual study [PDF]:
Risks from combined exposure to spousal and workplace ETS were higher for squamous cell carcinoma and small-cell carcinoma than for adenocarcinoma, but the differences were not statistically significant.
Translation: "Sure we found an increase, except that the increase was not greater than that which could attributed to statistical error. Okay, we didn't really find anything, but hopefully people will only read the press release."
Apparently, the WHO will not let a silly little thing like scientific and academic integrity get in the way of its mission to use the force of government to protect us from ourselves. In bars. While we drink poison.
(H/t: Penn Jillette)