Acute infections caused by pathogenic microorganisms have been studied extensively for over 100 years. Infections that killed millions of people in the past are now ever more successfully controlled due to the development and use of antimicrobial compounds. Biocides, in particular, have been used in various forms for many centuries to control the dissemination of microorganisms and represent a wider group of substances with a key role in the medical and food industry. This chapter presents the main biocidal classes and mechanisms of action, including their respective spectrums of activity and use in several fields. Factors influencing the effectiveness of biocides are addressed as well as biocide resistance and the link with antibiotic resistance. Several mechanisms of biocide resistance are presented on a molecular level with a particular focus on biofilm resistance and its formation in bacterial populations. This chapter concludes with an introduction to ECHA, the European Chemicals Agency and their recently approved regulatory framework for biocide products in Europe.
Keywords: Antimicrobial Resistance, Biocides, Biofilm, Concentration, Contact Time, Cross-Resistance, Disinfection, ECHA, Effectiveness, European Union, Exopolymeric products, Legislation, Microorganisms, pH, Quaternary ammonium compounds, REACH, Regulation, Salmonella, Staphylococcus aureus, Temperature.