Contamination is the presence of an unwanted constituent, contaminant or impurity in a material, physical body, natural environment, workplace, etc. Contaminants are biological, chemical, physical or radiological substance.
A man wants no protection when his conduct is strictly right.
William Murray, 1st Earl of Mansfield, Bird v. Gunston (1785), 3 Doug. 275; reported in James William Norton-Kyshe, Dictionary of Legal Quotations (1904), p. 212.