This article speaks for itself: Sindhu RK, Rasmussen RE, Kikkawa Y 1996 "Exposure to environmental tobacco smoke results in an increased production of (+)-anti-benzo[a]pyrene-7,8-dihydrodiol-9,10-epoxide in juvenile ferret lung homogenates." JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH 47:(6) 523-534 (APR 19 1996). Abstract: "Six-week-old ferrets were exposed head-only to clean air or environmental tobacco smoke (ETS) at an average particulate concentration of 38 +/- 13 mg/m(3) for 2 h/d, 5 d/wk for up to 15 wk. Twenty-four hours after the last exposure, the ferrets were sacrificed and the metabolism of benzo[a]pyrene and (-)-7R-trans-benzo[a]pyrene-7,8-dihydrodiol was studied in lung homogenates. The results show that after ETS exposure total metabolism of benzo[a]pyrene, measured by the accumulation of hexane nonextractable radioactivity, was increased by 35% in the males and 66% in the females (p <.05), respectively, of that observed with air-exposed controls. With (-)-7R-trans-benzo[a]pyrene-7,8-dihydrodiol as substrate, the formation of both benzo[a]pyrene-r-7,t-8,9,c-10-tetrahydrotetraol and (+)-anti-benzo[a]pyrene-7,8-dihydrodiol-9,10-epoxide-derived tetraols by lung homogenates of ETS-exposed male and female ferrets was significantly increased compared to the air-exposed controls (p <.01). DNA-bound radioactivity was significantly increased in both the males (p <.01) and females (p <.01) compared to the air-exposed ferrets." All I will say is, one of the primary causes of cancer is radioactive (or oxidant) mediated DNA damage, and what this paper says is, ferrets exposed to environmental cigarette smoke have large increases of DNA damaging radioactive particles in their lungs compared to ferrets breathing clean air, with females having twice the load as males (probably due to increased respirations). Without guessing what this means in terms of absolute cancer risk, it is clear ferrets (especially females) exposed to cigarette smoke will have a much higher relative risk of cancers cause by DNA damage. For those of you who do not understand what "males (p <.01)" means, it is a measurement of accuracy and precision. In this case, the finding is accurate and precise to 99%, meaning there is 1 chance out of 100 that the scientist is wrong. Standard scientific protocols require (p <.05), or 95% reliability, so this is well beyond what is required for scientific standards (even the space program is limited to 95%). Second hand smoke is NOT just the free smoke exhaled by the smoker or from the burning cigarette. It is also those chemicals which come off the clothing or walls, from the hair, skin, or even from the breath of the smoker. Many of these chemicals, including the nasty radioactive ones, form sticky pastes with the water and biochemicals from a smoker's lungs, and coat surfaces in the environment, only to evaporate into the air over long periods of time (this is why a nonsmoker can rent a hotel room and KNOW it was occupied by smokers, even after extended time or cleaning). With heavy smokers, the house itself becomes a hazard to those with small or damaged lungs, especially those who have naturally rapid breathing (like ferrets), because virtually ALL exposed surfaces get coated with the DNA toxins. Ferret caretakers addicted to nicotine may express anything they like concerning their drug addiction (including denial), and they have the freedom to place themselves at risk as they see fit, and I will not comment nor judge them for their decisions. But the case is clear that ferrets are negatively impacted in such a way that their risk of cancers caused by damaged DNA is increased above that of ferrets not exposed to second hand smoke. The individual owner has to decide if placing nonconsenting ferrets at risk is ethical, moral or demonstrates at high regard of ferret stewardship. In other words, these are the scientific facts; you will have to judge them for yourself, and learn to accept whatever risk you force on your ferrets. Bob C and 15 Mo' Nonsmokin' Stoats [Posted in FML issue 3190]