Safety assessment of residual amounts of disinfectants based on quaternary ammonium compounds on medical devices

Has been made an assessment of the toxicity of residual amounts of disinfectants after using them on products, made from various materials, with DS solutions based on QAC. The working solutions were used in concentrations from 0.3 to 7 % (by DV). The safety of the studied samples was assessed by the toxicity index "It" (in%) on an AT-05 Image Analyzer. Washing out of the residual amounts of DS in concentrations of 0.3–0.7 % (by DW) did not significantly affect the total time of disinfection treatment or pre-sterilization cleaning. At higher concentrations of solutions, there were differences in the time of washing test items and dishes for receiving safe amounts of DS. It is concluded that it is inexpedient to use solutions based on QAC in a concentration of more than 4.5 % (in terms of DV) for disinfection treatment and pre-sterilization cleaning of products made of natural and silicone rubber. Keywords: disinfectants, quaternary ammonium compounds, product washing, AT-05 image analyzer, to­xicity index.

Antimicrobial Agents for Textiles: Types, Mechanisms and Analysis Standards

The large surface area, and ability to retain moisture of textile structures enable microorganisms’ growth, which causes a range of undesirable effects, not only on the textile itself, but also on the user. Moreover, textiles used in health care environments are required to possess antimicrobial property to minimize spread of pathogenic infection. Anti-microbial property can be imparted via chemical finishing with an antimicrobial agent. Currently the use of antimicrobial agents includes metal compounds (notably copper and silver particle), chitosan, halogenated phenols “triclosan”, quaternary ammonium compounds, antibiotics (a class of antimicrobials produced from microorganisms that act against one another), and N-halamines. The possibility of bacterial resistance limits antibiotic use to specific medical applications, and triclosan is known for being dangerous to the environment and is currently under scrutiny for possible endocrine disrupting to human being. Although quaternary ammonium compounds are stable and easily manufactured, microbial resistance is also a concern. Quaternary ammonium compounds (QACs), Polyhexamethylene Biguanide (PHMB), chitosan and N-halamines are listed under bound or non-leaching type antimicrobials. The bulk of current chapter focuses on the different family of antimicrobial agents used for textiles and their mechanisms.