Solid waste pollution refers to the phenomenon of improper disposal of solid waste into the environment, leading to endanger human health or property safety, as well as damage to the ecosystem and cause deterioration of environmental quality. Which of the following are not polluted by solid waste? ['Factory A illegally discharges sewage into the Han River.', 'Clinic did not dispose of the used disposable syringes according to the regulations, but was randomly thrown on the roadside, picked up by a few three-year-olds, and accidentally scratched their fingers to infect them.', 'White disposable lunch boxes on both sides of the railway.', 'The uranium used in a university physics laboratory was not buried, and was found by a ragged person who died three weeks later.']