Ambient protein concentration in PM10 in Hefei, central China

The total protein associated with bioaerosol particulate matter (PM) is generally measured as an all-inclusive indicator of airborne biological material, which may enhance the effects of allergens, allergic and asthmatic responses. To investigate the level and seasonal variations of biological loading, PM10 were collected in a metropolitan area of Hefei, central China from June 2008 to February 2009 and analyzed for total protein mass, trace elements, and water-soluble ions. The protein concentration in PM10 ranged from 2.08 to 36.71 μg m−3 with an average of 11.42 μg m−3. This was the highest value reported so far in the literature. The total protein was found to have a significant correlation with the air pollution index (API) and mean visibility (VV), indicating the potential influence of anthropogenic sources and/or crustal sources. The protein content displayed an obvious seasonal variation with respect to weather conditions. In the rainy season the level of protein was low, while in the dry season and foggy weather the level of protein was relatively high. A correlation analysis revealed that the relationship between total protein concentration and water-soluble ions K+ and NO3− in PM10 during the dry season is 0.92 and 0.66 (P < 0.05), respectively, suggesting that anthropogenic pollution and biomass burning are main contributors during this period.

► Ambient protein concentration in PM10 in Hefei, Central China was investigated.
► The protein level was very high in comparison with the literature reports elsewhere.
► The protein content displayed obviously seasonal variation with respect to rainy and dry season.
► The anthropogenic pollution and biomass burning were mainly contributions during dry season.