INDOOR AIR-POLLUTION AND SICK BUILDING SYNDROME - MONITORING AEROSOL PROTEIN AS A MEASURE OF BIOAEROSOLS

Excess aerosol protein concentration is suggested to be a diagnostic m arker for biological causes of impaired air quality of a building. A s imple inexpensive instrument has been developed to measure aerosol pro tein concentration. Aerosol particles are collected by allowing inject ed steam to condense upon them, thus resulting in their growth, follow ed by cooling and impaction. The liquid stream, bearing dissolved and suspended aerosol constituents, is put through a silica preconcentrati on column that is eluted subsequently with dilute H3PO4. The eluite st ream is reacted with acidic Coomassie blue G; the color of the protein dye adduct is detected by optical absorbance at similar to 600 nm. Op timization efforts have been carried out to choose the best stationary phase for protein preconcentration and reagent composition. In liquid -phase experiments, bovine serum albumin (BSA) displays a limit of det ection (LOD) of 16 ng. In aerosol experiments, there is some increased noise and the LOD deteriorates by similar to 2x. The system collects aerosol particles with 99.5+% efficiency. The LOD for a 300 L (30 min at 10 L/min) air sample is thus equivalent to a concentration of simil ar to 100 ng/m(3) BSA. The system is mounted on a single two-tier stan dard laboratory cart and has the potential to be an effective transpor table monitoring device for airborne biological contamination. Detecta ble protein concentrations were found in an apartment dwelling setting during cooking activities and in a hotel known to have a fungal conta mination problem.