An evaluation of mass,number concentration,chemical composition and types of particles in a cafeteria before and after the passage of an antismoking law

摘要

This study assessed air quality indicators before and after enactment of the Spanish anti-smoking law.Mass and number concentrations and the chemical composition of particles were evaluated.Microscopy analyses were also conducted.Real time concentrations of PM_(10),PM_(2.5),PM_1 and ultrafine particles were measured under ventilated and non-ventilated conditions and PM_(10) samples were collected for detailed inorganic and organic chemical characterization.Before enactment of the law in 2010,tobacco smoke produced significant indoor ambient particulate matter pollution,with elevated particulate matter mass concentrations(PM_(10) and PM_1 concentrations of 122-220 and 48-85 μg/m^3,respectively) and ultrafine particle numbers(75,000 and 48,000 cm'3 under ventilated and non-ventilated conditions,respectively).Typical tobacco smoke tracers including iso- and anteiso-alkanes and elements including La and Ce from the ignition of lighters were abundant.Additionally,several toxic substances derived from tobacco smoke,including Cd(3.1 ng/m^3) and benzo[a]pyrene(1.0 ng/m^3) were present at concentrations approximately10 times greater than those measured after enactment of the anti-smoking law.The anti-smoking law significantly reduced exposure to potentially toxic compounds by approximately 90%.This law is expected to have a positive health impact,particularly for people who spend considerable time in affected environments,such as employees.