Many people do not rinse their dishes, glassware and cutlery when washing up, leaving a residue of detergent foam clinging to it – some people seem to relish the quantities of foam they generate and leave on dripping plates etc. Does the cumulative ingestion of a detergent residue create a hazard to health? Could hormonal changes and blood clotting be affected? Also, large quantities of detergents are going into waste water – could they be affecting marine life and ingested through the human food chain?

Diana Holbrook, Canterbury, Kent

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