Absent from your otherwise fascinating survey of towels and toilet brushes (Ditch your loo brush, 21 February) was any recognition of the weird psychology of cleanliness. Beyond a certain point, it becomes irrational. To get or follow instructions from an OCD cleaner is very problematic – just look at the extent of her daily routines (and the amount of water she uses for washing).

With OCD, a vivid imagination will supply all the motivation needed to spend every waking moment fighting against “dirt” seen or unseen. To those who have it, it is no joke; even worse is how the psychology can leach into the imaginary metaphysical world, with whole races, classes and genders becoming stigmatised as “unclean”.

Instead of condoning this new disinfectant onslaught, promoted by advertising and media articles like this one, but with very little epidemiological basis, we should be discussing the possible effects of excessive hygiene and its weakening effect on the human immune system. The simple tools designed for bacteria cannot fight viruses. Luckily, apart from the professional cleaners there were a few “normal” experts who were more relaxed about cleaning issues. Balances have to be struck. Humans are tough old animals and a bit of dirt may be no bad thing.

Virginia Smith

Author of Clean: A History of Personal Hygiene and Purity, London

• So have I got this right? I have to wash my towels every few days, change my sheets and pyjamas twice a week and wash them – including the mattress cover and pillows – take my shoes on and off every time I go into the garden to get the washing in and clean the floor if I forget, wash my jeans if I also wear them to get washing in, scrape the toilet twice a day, clean the bathroom and sort my dish cloths daily, wipe down every surface in the house, vacuum under the bed regularly and shower every morning and evening? Have you thought that I might have to cancel my Guardian subscription as I won’t have time to read it?

Mike Hoskin

Hinton St George, Somerset

• Rarely has an article in the Guardian so enraged me. In these days of heightened climate change awareness you have experts who encourage washing tea towels daily and washing bath towels daily. Who are these people? Apart from the blindingly obvious fact that bath towels dry theoretically clean people is the expert completely oblivious to issues such as water scarcity, carbon-producing energy to power her machines, microfibres being released into our ever more polluted waterways and eventually the sea? Heaven forbid that after washing her towels daily she then tumble dries them – such a delicate person I am sure would never use anything so practical as an outdoor washing line (think of all those nasty birds flying around who might drop something on the drying). The article gave out such a bad message. We should be washing less, not more.

Nicky Ford

Guildford, Surrey

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