Hospital wastewater (HWW) can contain hazardous substances, such as pharmaceutical
residues, chemical hazardous substances, pathogens and radioisotopes. Due to these
substances, hospital wastewater can represent a chemical, biological and physical
risk for public and environmental health. In particular, several studies demonstrate
that the main effects of these substances can't be neutralised by wastewater treatment
plants (WWTPs). These substances can be found in a wide range of concentrations due
to the size of a hospital, the bed density, number of inpatients and outpatients,
the number and the type of wards, the number and types of services, the country and
the season. Some hazardous substances produced in hospital facilities have a regulatory
status and are treated like waste and are disposed of accordingly (i.e., dental amalgam
and medications). Legislation is quite homogeneous for these substances in all industrial
countries. Problems that have emerged in the last decade concern substances and microorganisms
that don't have a regulatory status, such as antibiotic residues, drugs and specific
pathogens. At a global level, guidelines exist for treatment methods for these effluents,
but legislation in all major industrial countries don't contain limitations on these
parameters. Therefore, a monitoring system is necessary for these effluents as well
as for substances and pathogens, as these elements can represent a risk to the environment
and public health.