§ Mr. Ron Davies
To ask the Secretary of State for Wales what steps are being taken by the Welsh water authority to reduce aluminium levels in water supplies in Wales.
§ Mr. Ian Grist
The Welsh water authority has an on-going programme of remedial works to water supplies in Wales containing levels of aluminium above that specified in EC directive 80/778/EEC (the drinking water directive). These works are part of an overall programme, which will be mostly completed by 1990, to ensure that all drinking water supplied complies with the provisions of the directive.
§ Mr. Ron Davies
To ask the Secretary of State for Wales what studies have been conducted by his Department, the Welsh water authority and other bodies, respectively, into a possible link between high aluminium levels in water and senility; and if he will make a statement.
§ Mr. Grist
No such studies have been conducted by the Department or the Welsh water authority.
Research at Southampton university is said to indicate a correlation between Alzheimer's disease (which causes premature senility) and aluminium in drinking water. The report has not been published and so it is not yet possible for medical advisers to comment. When it is published it will be assessed and appropriate action taken if necessary.
In the United Kingdom and many other countries, aluminium salts are used widely as coagulants in water treatment to remove undesirable suspended contamina-tion and potentially harmful bacteria. Aluminium can also occur naturally in some raw waters. In the United Kingdom, however, the concentrations of aluminium in tap water are controlled mainly by the efficiency with which aluminium is removed during water treatment, irrespective of the source of aluminium.
The current standard which the Government have adopted, after taking advice from medical experts, for aluminium concentrations in drinking water is that contained within directive 80/778/EEC (the drinking water directive). Most water supplies comply and, where they do not, the Welsh water authority has a programme of remedial action.