Health Stream Article - Issue 25 March 2002

Camelford Incident Reviewed

The working group set up by the UK Government to re-examine the health effects of the alum overdosing incident that occurred in Camelford, North Cornwall in 1988 has commenced its investigation. The new investigation was announced by the Department for Environment, Food and Rural Affairs in August last year, but the membership of the group was not finalised until January.

The group comprises five members of the Committee of Toxicity of Chemicals in Food, Consumer Products and the Environment (CoT) with expertise in toxicology, epidemiology and child health, plus two local representatives nominated by the local Member of Parliament. The chair is Professor Frank Woods of the University of Sheffield, who also chairs the CoT.

The terms of reference for the investigation are:
· to advise on whether the exposure to chemicals resulting from the 1988 Lowermoor water pollution incident has caused, or is expected to cause, delayed or persistent harm to human health; and
· to advise whether the existing programme of monitoring or research into the human health effects of the incident should be augmented and, if so, to make recommendations.

Camelford is a small town of about 2,500 people situated in Cornwall. The contamination incident occurred in July 1988 when a contractor dumped 20 tons of aluminium sulphate into the wrong tank at the Lowermoor treatment plant operated by South West Water. The plant was an unmanned installation and the contractor was a relief driver unfamiliar with the plant layout and delivery procedures. The resultant acidic water entered the water supply directly, causing public complaints about the taste, skin irritation and corrosive effects on plumbing and fixtures, however the cause of the problem was not determined for two days. The public were assured by a spokeman for the water authority that the water, while tasting slightly acidic, was safe to drink.

It was estimated that consumers were exposed for up to three days to water with pH as low as 3.9 to 5.0. An aluminium content of up to 620 milligram per litre and a sulphate concentration of up to 4,500 milligram per litre were recorded in the water supply. Once the cause of the problem was determined, a program of flushing reduced levels rapidly to 1 milligram per litre.

Over the following months more than 400 of the town's residents complained of a range of symptoms including skin rashes, arthritic pains, sore throats, loss of memory and general exhaustion. These complaints were investigated by health authorities and the government appointed the Lowermoor Incident Health Advisory Group to report on the health effects of the incident. In two reports delivered in 1989 and 1991, the Advisory Group concluded that there was no convincing evidence that harmful accumulation of aluminium had occurred, nor that there was a greater prevalence of ill health due to the toxic effects of the contaminated water. The report also stated that the Advisory Group recognised that the incident and subsequent events had led to real suffering in the community, but attributed this to anxiety rather than direct health effects; a conclusion which angered many residents.

Since the incident, over 700 claims for damages have been paid with individual amounts ranging as high as 10,000 pounds. The South West Water Authority was prosecuted for causing a public nuisance, fined 10,000 pounds and ordered to pay 25,000 pounds in costs. The concerns of residents over the health effects have not declined in the intervening 13 years, and there has been an ongoing campaign for a full public inquiry. The new inquiry is believed to have been prompted in part by research conducted in 1991, but not published until 1999 for legal reasons, reporting disturbances in cerebral function associated with the incident (1).

The new investigation is more limited in nature than a public inquiry, however its Chair has commented that the lack of formal legal proceedings and cross-examination may allow individuals to be more freely forthcoming in their evidence. The working group will hear personal testimony from individuals who believe their health has been affected, as well as reassessing the evidence evaluated by previous inquiries, assessing more recently published studies and analysing local area health statistics. While the investigation will focus on the toxic effects of aluminium, possible exposure to other substances that may have occurred as a consequence of the incident including copper, zinc, lead, sulphate and hydrogen ion will also be assessed. The group is expected to complete its work in March 2002.

(1) Reviewed in Health Stream Issue 16 - From the Literature section. Disturbance of cerebral function in people exposed to drinking water contaminated with aluminium sulphate: retrospective study of the Camelford water incident. Altmann P, et al. British Medical Journal (1999) 319 (7213) p807-11.