In-reservoir destruction of Blue-Green Algae and their toxins

Lead Research Organisation: The Robert Gordon University
Department Name: School of Pharmacy and Life Sciences

Abstract

One of the greatest global challenges currently facing human-kind is access to reliable safe clean drinking water. This is particularly acute in developing countries where human activities often adversely impact water quality. While the earth is known as the blue planet with 71% of its surface covered in water, nearly all of this is seawater and not suitable for human consumption or is utilised in industrial and agricultural processes. Only a tiny proportion of the earth's water is freshwater (about 3%) and of this less than 1% is available for use, since much of the remainder is frozen at the poles or in glaciers. Water levels and quality in drinking water reservoirs across the globe are seriously depleted with the United Nation predicting that 1.8 billion people will suffer serious recurrent water shortages by 2025 and two thirds of the population living in areas of water stress.
Of the water that remains in these depleted reservoirs, nutrient (nitrate and phosphate) levels from agriculture, industry and domestic waste are found to be high resulting in the mass growth of blue-green algal blooms along with the production and release of dangerous toxins. These toxins can cause acute and chronic symptoms in humans and animals resulting in ill-health, fatalities and cancers. When present in high numbers traditional water treatment often fails to eliminate the blue-green algal cells resulting in human exposure. Furthermore, the toxins they produce are also very stable during treatment allowing them to pass unaltered into drinking water. Innovative water treatment to eliminate these problems which uses light and a simple catalyst (TiO2 photocatalysis) has been pioneered by Professor Linda Lawton (Environmental Microbiologist - RGU) and Professor Peter Robertson (Chemical Engineer - QUB). We have successfully demonstrated the rapid and effective removal of 4 out of the 6 classes of toxins (evidence suggests the remaining 2 classes, saxitoxins & BNAA, will be easily destroyed as they are more simple chemical structures). Furthermore, we have also shown that the same treatment is effective against harmful microbes in water.
We have extensively evaluated this exciting technology both in the laboratory and on a pilot scale with considerable interest from water utilities in seeing the full implementation within the provision of drinking water. One limiting factor has been developing a simple strategy to expose and illuminate catalyst in contact with water while ensuring that the catalyst can be readily removed. The most efficient destruction has been found for nano-particulate catalysts which cannot easily be removed from water. We aim to transform the approach to dealing with blue-green algal contamination of reservoirs by developing and testing exciting new photocatalytic treatment pods which are continually powered by integrated, floating solar panels which drive low energy LEDs. Professor John Irvine (Electrochemist - St Andrews) will bring his world leading expertise in catalyst modification and characterisation along with electro-optimisation. Dr Christine Edwards (Biotechnologist - RGU) along with Professor Lawton have led the field in the production and detection of cyanotoxins and we will collaborate with leading scientists in Brazil where reservoirs are currently extremely depleted and suffering from significant blue-green algal blooms and their associated toxins. This collaboration will allow us to test the in-reservoir deployment of our novel treatment system in water bodies which are consistently contaminated with blue-green algae and in an environment with excellent solar irradiation with which to drive the very low running cost treatment.
On completion of this research we will launch a fully scalable in-reservoir water treatment system which will be transferable to any developing or developed country to eliminate hazardous blue-green algal blooms, other pathogens and a wide range of toxic pollutants.

Planned Impact

Water quality and scarcity, impacted by extreme weather events and human activity, represents one of the great, global societal challenges. In particular domination by hazardous blue-green algae as a consequence of eutrophication, poses a threat to animal and human health in addition to reduction of ecosystem function. According to the Global Water Partnership of South America, 20 million people have no access to clean drinking water.
To address this challenge, the UN have established a Sustainable Development Goal 6.1. to ensure clean water for all by 2030. To contribute this goal, the multidisciplinary team of established experts, aims to develop an efficient, low cost, in-reservoir treatment rig, exploiting the well proven (RGU) rapid cell/toxin destruction capability of the photocatalyst TiO2 in suspended novel fabricated pods. The outcome of the 3 year project will deliver a treatment rig that can remove blue-green algae and associated cyanotoxins (along with other pollutants and pathogens) to provide improved water quality for direct use such as irrigation/livestock or for clean drinking water. Provision of good water quality will have positive economical, social and environmental benefits. This approach focuses on the blue-green algae, their toxins and other organic pollutants without damaging other essential components of the aquatic ecosystem. Whilst the focus of the project is aimed at water treatment in developing countries, it will be an invaluable tool for all water providers.
Fabrication to application will be key to the project, ensuring that rig construction is local to target site(s) and may be custom designed for each water body based on project model which is simple and scalable, providing jobs contributing to economic growth. The versatility of the system will be essential for deploying in rural communities where 20 million people do not have access to safe, clean water, providing more local solutions avoiding complex infrastructure issues.
Close collaboration between project team and supporting academics and industries along with dissemination of project milestones will be communicated to stakeholders for maximum exposure and future application. A focused symposium on the project in the context of improving water quality with global deployment of the rigs will be held at the end of year 2, inviting water management experts/public health/environmental agencies from all continents providing a platform for future actions and activities. These will also include representatives of the key organisations tackling global water security and management such as UN FAO, WHO, OECD, IWA and WaterAid. In addition to in-situ reservoir treatment, the proposed strategy will have potential application for remediation of fresh and marine waters (for example removal of taste and odour compounds in aquaculture ponds). The interactive, international nature of the project, led by scientists with a proven track record of delivering high impact publications/solutions will underpin the development of the PDRAs, to deliver innovative scientists for the future, aware and capable of sustainable research and development challenges.
In addition to contributing to improved water quality in Brazil with a sustainable, safe, low cost and robust treatment solution, the availability of improved water will be essential for economic growth where there is huge demand on water for hydropower, agriculture, industry and domestic use. Extensive knowledge transfer/training throughout the project will facilitate the development of a centre of excellence at UFC, Brazil, for detection and treatment of blue-green algae and their toxins. Further, significant impact will be achieved as a consequence of this high quality research through generation of multiple, high impact publications, technology patents and extensive public/industrial engagement.

Publications

10 25 50
 
Description We have developed coated recycled glass beads that have the ability to photocatalitically destroy toxins in water. We have now tested the reactor successfully at scale in a reserviour in Brazil.
Exploitation Route They may be applied in other locations and for other harmful compounds for example trace pollutants.
Sectors Agriculture, Food and Drink,Chemicals,Energy,Environment,Pharmaceuticals and Medical Biotechnology

 
Description Scottish Government Hydro Nation Scholars Programme
Amount £147,500 (GBP)
Organisation Government of Scotland 
Sector Public
Country United Kingdom
Start 10/2020 
End 09/2024
 
Description Scottish Government Hydro Nation Scholars Programme
Amount £147,500 (GBP)
Organisation Government of Scotland 
Sector Public
Country United Kingdom
Start 10/2019 
End 09/2023
 
Description Engagement with water company end-users 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Professional Practitioners
Results and Impact 20 water treatment operators and R&D staff attended a series of talks by project partners to present prototype photocatalytic reactors and discuss application of the technology beyond the scope of the funded project. Feasibility of production in Brazil with locally sourced materials was discussed.
Year(s) Of Engagement Activity 2019
URL https://portal.cogerh.com.br/projeto-internacional-de-melhoria-da-agua-conta-com-o-apoio-da-cogerh/
 
Description Information workshop for Water resourse managers and water treatment engineers (Fortaleza, Brazil) 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Industry/Business
Results and Impact Information event and discussion with company employees involved in managing reservoirs and providing drinking water, to raise awareness of the development of novel treatment strategies.
Year(s) Of Engagement Activity 2018
 
Description TOC training workshop 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact Training water services staff in the analysis of water to support ongoing research and routine analysis.
Year(s) Of Engagement Activity 2018
 
Description Training workshop on cyanotoxin analysis 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Industry/Business
Results and Impact Cyanotoxin training workshop with hands on LC-MS with comparison to routine ELISA detection, answer questions.
Year(s) Of Engagement Activity 2018