The WHO Study
Pub Date: 1/1/2003
The World Health Organization's environmental tobacco smoke study is a textbook example of the right way to go about epidiomological research, but, unfortunately, much to the agency's chagrin, the information gathered was inconclusive.
The WHO study was conducted in 12 cities in seven European countries over a period of seven years beginning in the early 1990s.
The participants consisted of 650 patients with lung cancer and 1,542 control subjects. The stated purpose of the study was to provide "a more precise estimate of risk" to environmental tobacco smoke (ETS), to discover any differences between different sources of environmental tobacco smoke and to measure the effect of ETS exposure on different types of lung cancer.
What the study found was that there was no statistically significant risk existing for non-smokers who either lived or worked in the presence of ETS. (In fact, the only statistically signficant number the study turned up was a decrease in the risk of lung cancer among children of smokers.)
In more definite terms, the study found a Relative Risk (RR) for spousal exposure of 1.16 with a Confidence interval of .93-1.44. In layman's terms, that meant exposure to ETS from a spouse increases the risk of lung cancer by 16 percent. Or, where you'd normally find 100 cases of lung cancer, you'd now find 116.
Now a 16 percent relative risk was no small potatoes. Problem is, with a confidence interal (CI) of .93-1.44, the RR was just as likely to be 1.0 (or no increased risk) as it was to be 1.16 or any other number within the range of the CI. (Researchers generally want a RR no lower than 2.0 and prefer those around 3.0 in order for the finding to be considered scientifically significant.)
The relative risk for ETS in the workplace presented a similar problem when it came in at 1.17 with a confidence interval of .94-1.45. Again, the relative risk was well below the preferred 2.0 to 3.0 and the confidence interval again straddled the 1.0 mark.
Together, exposure from both a smoking spouse and a smokey workplace was 1.14 with a confidence interval of just .88-1.47.
As would be expected, the WHO quickly buried its report. But the British print got wind of the study and, following a legal battle, were granted access.
On March 8, 2002, the London Daily Telegraph reported, "The world's leading health organization has withheld from publication a study which shows that not only might there be no link between passive smoking and lung cancer, but that it could even have a protective effect."
In response, the WHO issued its own press relase, stating firmly, "Passive smoking does cause lung cancer."
They explained, "The study found that there was an estimated 16 percent increased risk of lung cancer among nonsmoking spouses of smokers. For workplace exposure, the estimated risk was 17 percent. However, due to small sample size, neither increased risk was statistically signficant."
On the other hand, the researchers who actually authored the study stated very different ideas in the Journal of the National Cancer Institute, the publication where the report finally appeared.
"An important aspect of our study in relation to previous studies is its size," they wrote. "(It) allowed us to obtain risk estimates with good statistical precision "
Conclusions
The conclusion of our own meta-analysis is not that ETS poses no health risk, but that the science claiming that it does is inconclusive and often unreliable.
If ETS is really as dangerous as the EPA, political organizations and activist groups claim, efforts to limit it could be justified.
But until indisputable evidence is produced that would prove such risk, the most reasonable attitude would be to respect the freedoms granted to smokers and business owners under the law.
The logical course, then, would seem to be to post notice at a business entrance advising the public of the presence of environmental tobacco smoke, then give people the freedom to choose whether or not they will accept exposure to the potential risk.
Source: Extra, a special supplement to The Montana Tavern Times, Dec., 2002, published monthly by Continental Communications, 125 W. Granite St., Suite 102, Butte, MT 59701.