Dried bird droppings are usually considered as a pollutant because they carry bacteria, parasites and other pathogens. The feces of birds contain urine, digestive residues and metabolites, which will pose potential risks to human health. Contact with dry bird droppings can lead to bacterial infections, such as salmonella and Escherichia coli. Birds carry parasites, such as ticks and fleas, which can be transmitted to humans through bird droppings. Direct contact with or ingestion of dry bird droppings can lead to health problems.