Trapping carcinogens such as tobacco-specific nitrosamines (TSNA) in environmental tobacco smoke (ETS) is a challenge for the application of zeolite in environment protection because most TSNA exist in the particles whose size exceed the micropores of zeolites. In this paper, a new strategy to intercept the particles and to trap the TSNA in smoke by use of the porous calcosilicate material with fiber-like morphology plus two-dimensional eight-ring channel system is depicted and assessed. Owing to the specific fiber-like morphology and chemical composition, zeolite-like calcosilicate CAS-I can effectively intercept the particles and thus reduces the TSNA level of mainstream smoke in the range of 30-60% once it is added into the cigarette filter, which is superior to zeolite NaA additive with the same amount. Moreover, the importance of morphology of zeolite-like porous materials on the adsorption of nitrosamines in smoke is reported for the first time. (c) 2009 Elsevier B.V. All rights reserved.