Wash your windows to clean the air

Dirty windows may worsen smog, according to Toronto chemists who say urban grime may help recycle nitrogen oxides into the air.
Susannah Handley and her team from the University of Toronto recently reported their findings online ahead of an article in the journal Environment Science and Technology.
The researchers say window grime contains inactive nitrogen compounds that have been deposited from air pollution, as well as an oily mixture of organic compounds, including bird poo.
The researchers did a study suggesting that the nitrogen compounds in this grime can convert back into pollution-generating nitric oxides in the presence of sunlight.
“Given the significant amounts of nitrate and potential photosensitizers present in urban films, this renoxification could be an important source of photochemically active nitrogen oxides in urban environments,” the researchers conclude.