2010-Development of Methods to Monitor Changes in Skin Bacterial Populations to Assess the Effect of Fabrics

Development of Methods to Monitor Changes in Skin Bacterial Populations to Assess the Effect of Fabrics

Rachel McQueen, University of Alberta, Canada


Introduction

Movement of liquid moisture and moisture vapour through clothing systems has been a priority area of textile research for several years. This is due to the critical role moisture transfer has on dissipating heat from the body.
Protective clothing in particular can inhibit moisture transfer by providing semi-permeable or completely impermeable barriers to protect the wearer from external heat,
cold, or chemical hazards. The problem associated with poor moisture transfer and excessive moisture accumulation at the skin/clothing interface does not just affect heat transfer through/in clothing systems, but also influences the susceptibility of the wearer to skin irritation and rashes, as over-hydrated skin is more susceptible to abrasion and inflammation.
Bacterial populations have been found to alter both in numbers and composition by occluding the skin with impermeable barriers. This is due to alterations in factors such as moisture content, transepidermal water loss, pH, PCO2 on the skin surface, and local skin temperature. Morphological changes to the skin surface, such as deepening of the
skin furrows, can occur through occlusion.
This can make the skin susceptible to penetration of allergens or irritants, and sweat itself can act as a primary skin irritant. Alterations in the skin function could also create conditions for transient microorganisms to proliferate where they may not have been
able to reside on normally functioning skin. This could occur in occupational-related circumstances where it may be difficult to retain a certain level of cleanliness (eg., soldiers in the field).
Several investigators have examined the movement of water vapour and liquid through fabrics, although none have specifically addressed the effect on bacterial populations and skin physiological function. In woven fabrics of comparable structures, water vapour transport was found to depend on characteristics of the fibre.
Hygroscopic fibres have the ability to sorb and desorb vapour from the air and may act as a “buffer” when changes in humidity occur within the skin/clothing microclimate. Water vapour transmission has been found to be influenced by porosity and thickness in polyester knit fabrics, with the thin, more open-knit constructions dissipating vapour
readily.
The influence of hygroscopic fibres for water vapour transport may be more important in
thick or tightly woven/knitted constructions, as movement of water vapour through air spaces within the textiles may be limited.