From breathing life into ancient oceans to spawning life threatening illness; both good and bad, microbes are responsible for all life on earth. One negative effect of microbes is the smell produced when bacteria break down the uric acid in animal urine. Once dry the bacteria will remain dormant in crystalized form. However, unless the bacteria are completely destroyed the smell will persist. While there are numerous liquid preparations designed to remove urine odor, removing the smell of cat pee from items such as books requires a different approach.
Open the books and sprinkle each page with baking soda. Be sure to cover all areas of the books, including the covers and bindings.
Place a table in the direct sun a hot day. Stand the books on their ends, inside the plastic bags,
with the cover and pages open to allow to maximum airflow inside the books. Place the thermometer inside the bag, near the opening, and seal the bag with a twist tie.
Allow the books to stand in the sun for two to three hours. Open the bag just enough to fit your hand inside to reach the thermometer. Do not open the bag more than necessary or you will allow too much heat to escape.
Read the thermometer. Once the temperature reaches 140 degrees Fahrenheit the bacteria will be destroyed.
Remove the books from the bag and brush off the baking soda with a clean dry cloth.