Chemical resistance testing of plastics: material compatibility of detergent and disinfectant products

Abstract

Surface cleaning and disinfection is a key part of breaking the chain of transmission and reducing the risk of healthcare associated infections. However, if cleaning and disinfectant formulations are incompatible with surface materials, frequent application can cause premature failure of plastics due to environmental stress cracking (ESC). Material compatibility should be considered when selecting cleaning and disinfecting products. This study evaluated the tendency of 2-in-1 wet wipes to cause ESC in commonly found healthcare plastics. Eight ready-to-use 2-in-1 wet wipes were evaluated for their ability to cause ESC in 13 plastic surfaces in accordance with BS EN ISO-22088-3. Polymers were exposed to fluid extracted from wipes at a fixed strain of 0.5% for seven days and assessed for cracking, crazing, and tensile strength in accordance with ISO 527-2:2012. All 2-in-1 wet wipes tested contained ESC agents, although the severity of ESC varied. Products with higher pH (>8.0) were responsible for 74% of failures, with 22 of the 39 tested plastics visibly cracking. Although the primary active in all tested wipe formulations were quaternary ammonium compounds, formulations that included small/medium amines or alcohol demonstrated a greater propensity for plastic cracking. Each disinfectant formulation exhibits a unique spectrum of microbial efficacy and unique potential to cause surface damage. This may result in device failures and recalls that could compromise patient and staff safety. BS EN ISO-22088-3 can support material compatibility assessments of disinfectant and detergent products before they come to market.