“…It is also noted that the possibility has not been ruled out that there are some specific forms of the heterogeneous syndrome of asthma that could be sensitive to these pollutants, as has been shown by Cowan, et al 37 and Mantel,38 nor has the possibility been ruled out that other pollutants that exhibit different temporal patterns from those of SO2 or smk may be related to the events identified, nor the possibility that higher concentrations of SO2 and particulates than those observed in this study might produce large numbers of asthma attacks.…”