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.



1. Responsibilities for enforcement measures in respect of cyanobacteria in inland and inshore waters fall into four general areas. These are, (i) minimising the incidence or severity of algal blooms by control of aquatic eutrophication or treatment of affected waters, (ii) minimising the scope for direct contact with affected waters for people (workers and the general public) and animals, (iii) control of cyanotoxins in drinking water and (iv) control of algal toxins in food.

2. Enforcement provisions are further complicated by the large number of "stakeholders" involved. Table 9.1 therefore gives a general overview of their roles and responsibilities in this connection.

Table J.1: A general overview of the interests and responsibilities of various stakeholders relevant to enforcement of provisions for mitigating the risk of health effects due to cyanobacteria in inland waters.

Stakeholder Interests and responsibilities
Water owners Owners have a general duty to be vigilant to any factors relating to their property that might reasonably be considered to present a risk to members of the public or to animals. A need for particular vigilance often applies in the case of children. Owners must also take reasonable actions to inform and protect those who might be at risk. In these connections, decisions of what was "reasonable" would ultimately be a matter for the courts.

The owner of the land on which a private drinking water source is located is responsible for controlling any activities on their land that might affect the supply to the extent that cyanobacterial mass growths might be such as to breach the quality standards.
Members of the public Members of the public are responsible for taking reasonable action to protect themselves, their children, and their animals.

Common law provides that persons may not recklessly or wilfully bring harm on themselves and then seek compensation from others. However, the extent to which they had done so would ultimately be a matter for the courts.
Health Protection Scotland (HPS) HPS is the principal focus in Scotland, within the NHS, for advice on issues relating to health risks associated with infectious diseases and environmental hazards, including water contamination related incidents. HPS carries out surveillance of algal, including cyanobacterial, incidents, which have affected or have the potential to affect human health, using the Scottish Environmental Incident Surveillance System (SEISS), an on-line electronic reporting system for SEPA, Local Authorities, and NHS Boards. Data on incidents are available via a password protected site to registered users, and annual reports are provided via the HPS weekly report and web-site.
National Poisons Information Service (NPIS) The principal source in Scotland for information on toxicology and clinical management for hazardous substances. NPIS manages TOXBASE, a database that provides information on toxicology and treatment for poisons (including cyanotoxins) to registered users.
NHS Boards NHS Boards in Scotland are accountable to the Scottish Government Health Directorates for the overall assessment of health needs of all people within their geographic areas, for arranging for those needs to be met and for providing public health advice to the public. They are also responsible for provision of medical advice to Scottish Water and (via the Health Board Competent Person (HBCP) to the local authorities. The local NHS Board should take the lead in co-ordinating the development of a LAP for its area.
Health and Safety Executive The HSE is responsible for enforcement of relevant "employers" legislation.
Employers Employers must comply with the general and specific provisions of the following legislation in respect of their employees and any members of the public that might be affected by their business: The Health and Safety at Work etc Act 1974.

The Control of Substances Hazardous to Health (COSHH) Regulations 2002 (as amended).

The Management of Health and Safety at Work (MHSWR) Regulations 1999

Specific provisions of the MHSWR include the need for risk assessments and these should include any risks associated with exposure to cyanobacteria or their toxins. Employers must then provide information, instruction, and training in respect of these risks and their mitigation, in order to ensure safe systems of work.
Scottish Government Enterprise and Environment Directorates (SGEED) SGEED has overall responsibility for the regulatory framework for the water industry in Scotland and through the office of the Drinking Water Quality Regulator (DWQR) is responsible for ensuring compliance by the Scottish Water with specified drinking water quality standards.

SGEED also oversee other legislation relevant to cyanobacteria in Scottish waters including :

The Bathing Water (Classification) (Scotland) Regulations 2008

The Surface Water (Fishlife) (Classification) (Scotland) Regulations 1997 (
The Surface Water (Abstraction for Drinking Water) (Classification) (Scotland) Regulations 1996 (Currently being reviewed) (

The Sludge (Use In Agriculture) Regulations 1989 (as amended). (

The Water Quality (Scotland) Regulations 2010. (
Drinking Water Quality Regulator for Scotland (DWQR) DWQR is responsible for ensuring compliance by Scottish Water with specified drinking water quality standards.

DWQR therefore ensures compliance with the Water Supply (Water Quality) (Scotland) Regulations 2001 (as amended).
Local Authorities (LAs), (mainly through Environmental Health Officers) The general powers and responsibilities for Scottish Local authorities are defined in the Local Government (Scotland) Act 1973 ). The general functions of LAs in relation to water quality are defined in Section 76F(1) of the Water (Scotland) Act 1980.

The Private Water Supplies (Scotland) Regulations 2006 ( ) define standards of wholesomeness in respect of water from private supplies for drinking, washing, or cooking or for food production purposes. The 2006 Regulations distinguish between supplies serving less than 50 persons that have no commercial activity associated with them (Type B supplies) and all other supplies (Type A supplies). LAs are the regulators and have powers and responsibilities for classification and monitoring of waters and for enforcement of the relevant provisions. Pollutants and blue green algae, to be monitored under these regulations are not specified precisely.

However, Section 76G(1) of the Water (Scotland) Act 1980 ( ) provides that where a local authority considers that a private supply is likely not to be wholesome; "the local authority shall, in the case of a private supply which is a Type A supply or may, in the case of a private supply which is a Type B supply serve a notice in relation to that supply on one or more of the relevant persons".

LAs also have general powers and responsibilities under the Local Government (Scotland) Act 1973 and the Public Health etc. (Scotland) Act 2008 ( for the protection of the local population from environmental hazards such as cyanotoxins in recreational waters.

LAs should co-operate with others in the development and implementation of the LAP
Scottish Water Scottish Water is responsible for the cleanliness and safety of public water supplies for homes and businesses throughout Scotland. Duties are defined by the provisions of:

The Water (Scotland) Act 1980 (as amended)
The Water Industry (Scotland) Act 2002 (
The Water Environment and Water Services (Scotland) Act 2003 ( )
The Water Services etc. (Scotland) Act 2005 ( )
The Water Supply (Water Quality) (Scotland) Regulations 2001
The Water Quality (Scotland) Regulations 2010

Enforcement provisions include surveillance and analysis for the presence of potentially hazardous substances including cyanotoxins in the water that they supply.

Scottish Water should co-operate with others in the development and implementation of the LAP
SEPA SEPA is responsible for ensuring compliance with environmental legislation, in particular:

The Control of Pollution Act 1974 (
The Environmental Protection Act 1990 (
The Environment Act 1995 (
The Water Environment (Controlled Activities) (Scotland) Regulations 2011 (SSI 2011/209)
The Bathing Water (Classification) (Scotland) Regulations 2008. (as amended).

SEPA will co-operate with others in the development and implementation of the LAP.
The Food Standards Agency in Scotland (FSAS) The FSA was established under the Food Standards Act 1999 ( as an independent food safety watchdog to protect the public's health and consumer interests in relation to food.

The FSA's principal interest in cyanobacteria is therefore any effect that they might have on the human food chain or on food processing. The FSA is not responsible for drinking water as supplied by a public or private water supply, but is responsible for bottled waters.

To fulfil the Community obligations as Competent Authority the Agency designates, monitors and controls production areas for live bivalve molluscs. The main concern in Scotland is biotoxins in marine shellfish in relation to which the FSA has powers and responsibilities under Regulation (EC) 854/2004.

Under Regulation (EC) 854/2004 ( FSA operates an official control monitoring programme to monitor for biotoxins in live bivalve molluscs from classified shellfish production areas, and for the presence of toxin-producing plankton in these areas. When toxins for Amnesic Shellfish Poisoning (ASP), Paralytic Shellfish Poisoning (PSP) or lipophilic toxins including Diarrheic Shellfish Poisoning (DSP) toxins are found to exceed the maximum permitted levels a Temporary Closure Notice (TCN) is made to close a classified area.

Wild King Scallops (Pectinidae) harvested outside classified areas in Scotland are also monitored for the presence of biotoxins. Where regulatory levels are exceeded for wild Pectinidae placed on the market they must be withdrawn and where appropriate the issuing of a Food Alert, and RASSF (Rapid Alert System Food and Feed) will be undertaken.

In addition, shellfish processors and their products must comply with all the statutory requirements in Regulation (EC) No 853/2004 ( which lays down the hygiene requirements for the production and placing on the market of live bivalve molluscs. The EC regulations are enabled by the Food Hygiene (Scotland) Regulations 2006 (as amended) ( If necessary, similar provisions could be made in respect of shellfish or fin-fish harvested from freshwaters in Scotland


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