As our infographic shows, the biggest known source of microplastic which enters our bodies is bottled water. Based on 4 separate studies, the average number of particles per liter is 94. Beer has the second highest number, at 32, but it is that in third place which may cause the most alarm. Air inhaled by humans, based on two studies conducted in France and Turkey, contains an average of 9.80 particles per m³. For reference, the EPA’s Exposure Factors Handbook says that a 31-51 year old inhales an average of 16 m³ per day.