If smelly sweat is your bane, then stop wearing polyester clothing. A new study by researchers at the University of Alberta explains how odorants transfer and are selectively absorbed by various fibre types in sweat.
- Different types of textile fibres have different odour profiles and intensities following next-to-skin wear.
- Polyester releases more odorants following contamination with sweat, leading to a complex odour profile when compared with cotton.
- Protein fibres, such as wool, typically have lower odour intensity, followed by cellulosic fibres, with synthetics such as polyester and nylon often perceived as more odorous.
RESEARCH AND ANALYSIS: Analysis of various fibres soaked in a solution of simulated sweat showed that cotton and viscose, which are cellulosic, or plant-derived fibres, absorbed — and consequently released — smaller amounts of odour-causing compounds than polyester, nylon and wool.
- The fibres were soaked in the sweat solution for different periods of time, then examined the release of various odour-causing compounds from those fibres using analytical equipment that can detect odorants in the air in real time — more like the human nose does.
- Overall, the study showed that the cellulosic fibres took in lesser amounts of the compounds when transferred through the sweat solution than textiles made of wool, nylon and polyester fibres, which conversely, initially released higher amounts of the smelly compounds.
- The study found that polyester fibres typically exhibited higher rates of release of VOCs or volatile organic compounds than either nylon or wool fibres/yarns during a 6–8 hour period.
THE CONTEXT: The sorption and subsequent release of odorous VOCs present in human sweat within apparel fibres/yarns can cause an unpleasant experience for end users. The problem can be exacerbated if odorants, or the source of odours, are not completely removed during laundering.
- Understanding how odours are generated, retained and released from textiles is vital to addressing this important consumer issue. Attending to the problem of odour in textiles has broader implications for the longevity of clothing, and facilitating textile reuse, which is essential for a circular economy.
- Body odours commonly transfer to clothing through liquid sweat, but investigation of odour retention in textiles often neglects this route of exposure in test procedures. Standard scientific methods include examining only how the odour passes through the air to the textile.
- By studying the transfer of odorants to fabrics using a liquid sweat solution, the researchers were able to give a more realistic insight into how these smell compounds really get into clothes, and also an explanation as to why some commonly worn fibres are smellier than others when people sweat.
THE PEOPLE: The research was conducted by Rachel McQueen, a clothing and textiles scientist in the Faculty of Agricultural, Life & Environmental Sciences along with colleagues from the University of Otago in New Zealand.
