Today consumers have shifted, and continue to shift, to doing their laundry at wash temperatures of 40˚C and below. This is due to increasing garment care label instructions for cold water washing and because of consumer care to avoid mixed/dark coloured items dye fading. More and more consumers also seek to reduce energy and monetary costs and are willing to make an effort towards more sustainable washing habits.
There has been a question raised if this recent trend in washing at cooler temperatures could lead to increased bacterial risks remaining on laundry after the wash. No health effects have been observed with these consumer habits. In Spain and Japan, for example, where people have been doing their laundry with unheated cold water for decades, there has been no reported increase of public health issues.
While cleaning garments at 40°C and below contributes to soil removal through mechanical action and surfactant aid, it does not provide total removal of bacteria. Under normal circumstances (i.e. no extreme soiling and no health issues) this will not create any health issues.
Most bacteria are indeed normal inhabitants of the human skin and guts and are harmless or even beneficial for humans. Only a small number are detrimental to health - these are called pathogenic. But washing at low temperature or below is safe for most of your normal loads. That is why the Center for Disease Control in the USA recommends regular washing cycles for normal laundry.
However there are certain high risk groups or situations where washing at cooler temperatures may not be sufficient. To investigate this further, In addition, P&G has consulted with public health experts to assess any risks from recent cleaning trends. It was concluded that in most domestic situations, there is no significant risk. In situations with specific vulnerable populations, they could be added reassurance by either washing at higher temperatures or using an anti-bacterial laundry additive. This is explained in the next section with tips for hygienic laundry.