Newspapers take about six weeks to decompose, while paper towels take two to four weeks. A paper bag takes about one month to decompose. The decomposition rate of paper depends on what the paper is made of, including any chemicals, fiber, coatings and contaminants.
Decomposition is the chemical dissolution of materials through bacteria and other biological means. The rate at which a material breaks down into the earth also varies based on the amount of sunlight, moisture and air exposure the material receives. Objects may take longer to decompose in landfills due to the lack of microbes. Newspaper and other kinds of paper decompose faster when wet.