Dog feces contain large quantities of bacteria and other microorganisms. High numbers of dogs in the urban environment and their habit to defecate on sidewalks, on playgrounds and in other places frequented by the general public means that such places are being contaminated with fecal materials. Rain and wind make this material airborn. Breathing may bring the microorganisms to human lungs and cause diseases. It is important to obey municipal bylaws and to collect dog feces and dispose of them properly in the toilets. Enhanced SEM. Image width: 19.7 micrometers. Magnification: 5,075x if the image is printed 10 cm wide.