Safety assessment of continuous glass filaments used in eclipse

Eclipse is a cigarette that produces smoke by primarily heating, rather tha n burning, tobacco. The Eclipse heat source assembly employs a continuous f ilament glass mat jacket to insulate the heat source. The glass mat insulat or is composed of continuous glass filaments and a binder. The purpose of t his article is to address the potential toxicological significance of the c ontinuous glass filaments under the conditions of intended use. Transfer da ta and the unique physical characteristics of the filaments demonstrate tha t significant exposure of the smoker will not occur. The available environm ental survey data clearly demonstrate that Eclipse smokers are extremely un likely to be exposed to continuous glass filaments at a level that represen ts a biologically significant increase over background exposure to glass fi bers. The chemical composition of the continuous glass filaments used in Ec lipse is generally similar to C-glass fiber compositions such as MMVF 11 th at have failed to produce either tumors or fibrosis in chronic inhalation s tudies conducted in rats. In vitro dissolution data demonstrate that the co ntinuous glass filaments used in Eclipse are more soluble than biologically active fibers such as rock wool ( MMVF 21) or asbestos. However, the conti nuous glass filaments used in Eclipse were not as soluble in simulated extr acellular lung fluid as representative C-glass fibers ( MMVF 10 and MMVF 11 ). In brief, exposure of Eclipse smokers to continuous glass filaments is e xtremely unlikely to occur at a level that may be construed to be of biolog ical significance.