RESPONDING to Dr John Furness of Darlington Memorial Hospital on water fluoridation (Echo, Sept 25), I would ask him to consider that fluorine is the most compact and reactive element in the universe, and it has no place in any living cell. It will readily replace calcium and can damage vital delicate enzymes and hormones.

Is he aware that current water fluoridation chemicals are industrial waste, containing significant levels of lead and arsenic?

Does Dr Furness know that mono-fluorophosphates in some toothpastes are sister compounds of nerve gases?

Fluoride is an endocrine disruptor, which delays tooth eruption, effectively skewing decay statistics. Children with late erupting teeth may be socially disadvantaged.

China and India have bitter experience of natural fluoride in groundwater, causing fluorosis, fertility problems and lower intelligence quotients.

Fluoridation is not working.

Recently, the Birmingham Mail described how West Midlands hospital admissions for extractions rose 300 per cent in three years in the under 10 age group, despite being fluoridated since 1964.

Has Dr Furness read the Iowa Fluoride Study? It concludes that the term “optimal fluoride intake” be dropped, and ingestion has no effect on tooth decay, but is strongly linked to fluorosis. Has he read the report from the American Dental Association Council on Scientific Affairs on preventing fluorosis in infants? The common factor is that it is now impossible to estimate our exposure to this poison.

M Watson, Darlington