Two methods to reduce paper waste are canceling junk mail like credit card and insurance offers and direct mail marketing and changing monthly paper statements to paperless emails. Junk mail alone accounted for 1.72 million tons of landfill waste in 2009.[73] Another method to reduce waste is to buy in bulk, reducing packaging materials. Preventing food waste can limit the amount of organic waste sent to landfills producing the powerful greenhouse gas methane.[74] Another example of waste reduction involves being cognizant of purchasing excessive amounts when buying materials with limited use like cans of paint.