Blue-Green Algae Science Limited

Rapid Testing Kits for Cyano-toxins in Freshwater

Vets may come across pets / livestock suffering from potential cyano-toxicity. Pet / livestock owners could be encouraged to bring a water sample to the vet for the vets to administer the cyano-toxin tests on the samples. This assumes that the owner has safe access to the water. Ideally the sample should be collected in a glass bottle, which the vets might supply. Speak to BGAS about practice rates for group orders. US treatment advice for pets/livestock is reported by Merck Manuals.

The treatment of drinking water containing cyano-toxins requires specialist advice. The World Heath Organisation offer some documentary advice on treatment guidelines, but consultant advice should be taken. Chlorination does not counter the effects of cyano-toxins and can, in some circumstances, create more risks. The Health Protection Agency / Public Health England stipulate that water should not be abstracted if contaminated with cyano-toxins, so you will need to take their advice on your special circumstances why you need to be abstracting water.

What to do if your water is cyano-toxic?

UK Guide

If you test strip result is over the safety level, firstly well done, you know you have a potential safety issue and can now act to protect water consumers and users. The following generic advice is based on UK practice.

First Response

The Environmental Agency should be informed by PHONE. The incident hotline is 0800 80 70 60. Please follow their  guides. Make them aware of either the visual signs of a bloom and / or the test strip results. Notify them of key water users at risk. Ensure they have the contact name of key staff to enable them to access the site. The Environment Agency will alert other authorities, like the Health Protection Agency (PHE) and Food Standards Agency.

Access to Water

Access to water should be prevented if the test strips indicate that cyano-toxins are present above the thresholds. A suitable number of warning signs should be stored on-site, stating that a harmful algae bloom has been detected. All critical access points to the water should display a notice. People, pets, and livestock should not access the water until the Agency have assessed the situation and advised the operator of the site accordingly. In relation to livestock, they may need moving to other fields or temporary electric fencing erected.

If the water or lake is to be used for a sporting event and safety levels have been exceeded, then access to the water should be prevented. The Environment Agency will follow the TRAFFIC LIGHT risk assessment procedure to advise you directly.

Frequent inspection of the erected warning signs and fencing should occur, with all items photographed to demonstrate that the operator of the site has acted responsibly. Remove any dead fish to ensure they are not eaten by other wildlife. Staff should use gloves, not risk entering the water and use fishing nets to recover dead fish.


If the water is being used for drinking water, especially for private water supplies, then the supply should be switched off and users informed. Water should not be used, even if boiled. Specialist advise may be needed to purge filters and the supply pipeline to ensure that the cyano-toxins have been removed from the water supply. It may be necessary to supply alternative bottled water to private supply users. Please remember that publicly accessible taps and field drinking troughs may need closing and purging.

Health Services

The Environment Agency will advise the local health services. It is often useful to have a list of local GP clinics and the nearby A&E addresses for the Environment Agency staff. Equally, the address for the local Council Environmental Health officers should be kept. Finally, we recommend informing local vets of the harmful algae bloom. Vets are often the first people to be informed of sick pets or livestock. The Health Protection Agency will coordinate actions, but it is useful to keep a check list.

WHO Guide (1999)

Water Treatment

Have a PLAN

Prior to a harmful algae bloom, have a plan for your site and the protection of the water. Make sure you have a stock of signs and have a list of contact addresses. Review the plan annually. You may have many action and response plans for your site, but this plan is about people's and animal's lives, so it is worth reviewing annually.

Health Protection Agency (2012)

Scottish Executive (2002)

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