INDEPENDENT STUDY: BioClad Hygienic Wall Cladding Reduces Bacteria on Kitchen Walls to 0%.
A microbiological analysis of BioCote-treated BioClad® PVC wall cladding installed in a food preparation environment. Date of study: October 2012.
Study Aim
This study aimed to compare levels of bacterial contamination isolated from surfaces in a busy kitchen situated in a UK care home. The study's main objective was to compare bacterial contamination on the antimicrobial hygienic wall cladding with other surfaces in the kitchen. The care home kitchen had been fitted with BioClad® PVC wall cladding (Advanced Hygienic Cladding Ltd, Harrogate, UK) at the time of construction in 2011. All walls in the rectangular-shaped room were fitted with BioClad® from ceiling to floor. The antimicrobial performance of the hygienic wall cladding was to be appraised according to the findings of the study.
Methods
Transport medium swabs were collected from various surfaces situated in working kitchen (Fig. 1) of a recently commissioned (2011) care home for the elderly located in the UK. Swabbing was performed by rubbing an object's surface area of 25cm2 (typically 5cm by 5cm) with the cotton tip of a pre-moistened bacterial transport swabs. Objects swabbed from the kitchen are identified in Figure 1. Swabs were transported to the microbiology laboratory for processing but kept at 4oC during transport. Bacteria collected on the swabs were transferred to two types of solid growth media; plate count agar and brain heart infusion agar containing 5% horse blood. Cultures were incubated in an aerobic environment at 36oC for 48 hours. After incubation, the amount of bacterial growth isolated from each swab was quantified by colony counting and the diversity of growth estimated by inspection of colony types. Isolates presenting a colonial appearance suggestive of a pathogen were Gram stained and presumptively identified.
Concluding statement
This study revealed a variety of bacterial counts on different kitchen surfaces. Numbers of bacteria isolated from the surfaces ranged from none (zero) detected to over 1000 colony forming units from 25cm2 sampling area. Only two surface types did not produce bacterial growth upon swab culture - BioClad® hygienic wall cladding and a suspended plastic ceiling tile. It does not follow that these surface were sterile (i.e. totally free from microorganisms) because bacteria may have been present on these surfaces that were not able to grow as colonies on the media used in this study, or the bacteria were present in such low numbers per unit surface area that the sensitivity limit of the isolation techniques used was exceeded.
Given the ease of demonstrating the presence of diverse bacteria from all other surfaces examined in the kitchen, it is reasonable to suppose those surfaces that yielded no bacterial growth on culture were not solely contaminated by non-cultivable bacteria rather numbers of bacteria on them were very low or, indeed, were absent. Thirteen swabs yielded no bacterial growth. Twelve of the thirteen surfaces swabbed were BioClad® hygienic wall cladding. A strong explanation for this observation must be the activity of BioClad's® antimicrobial feature of the hygienic wall cladding. Previous laboratory analysis of BioCote® treated BioClad® wall cladding according to the ISO22196:2011 protocol (Measurement of antibacterial activity on plastics and other non-porous surfaces) demonstrated this material to possess a potent antimicrobial property under laboratory conditions.
This study suggests its antimicrobial efficacy is transferable to the working environment.