As defined on www.defra.gov.uk

Clinical waste is defined in the Controlled Waste Regulations 1992. It means any waste which consists wholly or partly of:

which unless rendered safe may prove hazardous to any person coming into contact with it. And:

Clinical wastes are healthcare wastes that may prove hazardous to those that come into contact with them. There are stringent controls in place to ensure that clinical waste is managed safely and is recovered or disposed of without harming the environment or human health. Under the Environmental Protection Act 1990 it is unlawful to deposit, recover or dispose of controlled (including clinical) waste without a waste management licence, contrary to the conditions of a licence or the terms of an exemption, or in a way which causes pollution of the environment or harm to human health. Contravention of waste controls is a criminal offence. Section 34 of the Act, places people concerned with controlled (including clinical) waste under a duty of care to ensure that the waste is managed properly, recovered or disposed of safely and is only transferred to someone who is authorised to keep it.

In July 2005 the Hazardous Waste Regulations replaced the Special Waste Regulations and introduced new definitions of hazardousness for infectious and pharmaceutical wastes. Wastes that contain substances containing viable micro-organisms or their toxins which are known or reliably believed to cause disease in man or other living organisms are hazardous wastes (H9 infectious). Only cytotoxic and cytostatic medicines are hazardous. These are waste medicines possessing hazardous characteristics H6 toxic , H7 carcinogenic, H10 teratogenic or H11 mutagenic.