Scientists are reporting that so-called "thirdhand smoke" — the invisible remains¹ of cigarette smoke that deposits on carpeting, clothing, furniture and other surfaces — may be even more of a health hazard（健康危害） than previously² believed. The study, published in ACS' journal, Environmental Science & Technology, extends the known health risks of tobacco among people who do not smoke but encounter the smoke exhaled³ by smokers⁴ or released by smoldering⁵ cigarette butts⁶. Yael Dubowski and colleagues note that thirdhand smoke is a newly recognized contributor to the health risks of tobacco and indoor air pollution. Studies show that that nicotine⁷ in thirdhand smoke can react with the ozone⁸ in indoor air and surfaces like clothing and furniture, to form other pollutants⁹. Exposure to them can occur to babies crawling on the carpet, people napping on the sofa, or people eating food tainted¹⁰（污染） by thirdhand smoke.

In an effort to learn more about thirdhand smoke, the scientists studied interactions between nicotine and indoor air on a variety of different materials, including cellulose（纤维素） (a component¹¹ of wood furniture), cotton, and paper to simulate typical indoor surfaces. They found that nicotine interacts with ozone, in indoor air, to form potentially toxic¹² pollutants on these surfaces. "Given the toxicity¹³ of some of the identified products and that small particles may contribute to adverse¹⁴ health effects, the present study indicates that exposure to [thirdhand smoke] may pose additional health risks," the article notes.