Cyanobacteria (Blue-Green Algae) in Inland and Inshore Waters: Assessment and Minimisation of Risks to Public Health

Guidance to Directors of Public

Health, to Heads of Environmental Health in Local Authorities (LAs), and to others in

Scotland, on possible risks to public health of cyanobacteria (blue-green algae) in inland

and inshore waters. It updates previous guidance under the same title that was published

by the Scottish Government Health Directorate previously in 2002, and revised in 2007.


This is the second revision of the guidance document under the same title that was published initially by the Scottish Executive Health Department in 2002, and revised for the first time in 2007.

The approach advocated for managing the risks to human and animal health of exposure to cyanotoxins continues to centre on production and implementation of "Local Action Plans". These should be co-ordinated by the NHS Boards in Scotland and should be agreed by the various stakeholders identified herein.

This document includes guidance on the content and structure of these Local Action Plans and should be regarded as a resource to assist in their production, as well as fulfilling the requirements of Article 8 (cyanobacterial risks) of the Bathing Water Directive (2006/7/EC).

The Scottish Government Health and Social Care Directorates (SGHSCD) propose to review and, if necessary, reissue this guidance document every five years. However, it is recognized that the value of this guidance lies in its practical implementation. The SGHSCD would therefore welcome feedback, which should be addressed to the SGHSCD's Scientific Adviser at St Andrew's House, Edinburgh EH1 3DG. Should this feedback indicate a specific need, then a further version of this guidance will be produced sooner.

The impact on human health associated with cyanobacterial contamination of recreational and drinking waters in Scotland remains, thankfully, low based on evidence of incident reports. The potential risks to health, however, remain real. Climate change predictions suggest that over a longer term, changes in temperatures and weather patterns may increase the scale of hazard presented by cyanobacterial blooms. This in turn may increase the scale of risk to human health. Planning and preparedness with respect to cyanobacterial contamination will therefore remain important for the foreseeable future.

Dr Colin Ramsay
Chairman of the Blue-Green Algae Working Group


Email: Janet Sneddon

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