Abstract: The present invention is related generally to a method for screening subjects to determine those subjects more likely to exhibit a hypersensitivity to allergen in the presence of airborne pollutants, such subject having a GSTM1 null genotype and/or a GSTP1 Ile/Ile genotype. This invention also provides novel or improved pharmaceutical compositions and therapeutic strategies for the treatment of immune diseases resulting from inappropriate or unwanted immune response such as allergic reactions.