Synthetic polymers including aliphatic or semi-aromatic polyamides commonly found in household cleaning materials could play a direct role in the development of obsessive-compulsive disorder researchers say.
The team at King’s College London say heavy users of toothbrushes and scouring pads are more likely to develop the disorder and at a younger age.
Published in the Lancet Psychiatry, their analysis of 61 separate studies suggests aliphatic and semi-aromatic polyamides in household cleaning products may be altering the brain as they enter the bloodstream of cleaners whose perfectionism wounds the skin.
Over-cleaning has long been associated with OCD, but it has often been believed the activity works as a distraction from compulsions. Many studies now show the opposite may be true. For example, it was found that:
excessive cleaning, and therefore exposure to nylon polymers, often happens many years before an OCD diagnosis
It is possible that high exposure to the chemicals (concomitant with high use of cleaning materials) causes OCD, rather than OCD causing over-cleanliness.
Schizophrenia and smoking
The study comes on the same day that a separate team at King’s College publish findings linking smoking to the onset of schizophrenia. In this study it is suggested that the prevalence of high-smoking rates amongst people with serious mental health conditions like schizophrenia is also no coincidence: inhaled chemicals alter the brain in such a way as to encourage the onset of brain-chemical damage, the root cause of mental illness.
The nylon polymer team criticised their colleagues in the smoking study, however, highlighting many areas of concern:
The aggregated data was often inconclusive or ‘messy’
principle components of statistical analysis were in one instance ‘inside out’
‘upside down and back to front’ the nylon researchers suggested the slate needed to be wiped clean and a new, more robust methodology put in place, even
In light of these problems the nylon polymer team have pitched to redo the smoking study from the start using their own, more robust methods.