Shellfish has the potential to become one of the largest future mainstream food in the UK due to its health, ethical and sustainable benefits. Oysters, mussels and clams are recognised as environmentally friendly and sustainable compared to other types of farming. In the UK, the shellfish sector was worth £11.7 million in 2016 with a signification growth of 60% in the past 10 years, reaching its highest level of 7,732 tonnes in 2016. Shellfish is also a sustainable food source. They do not require feeding, as they filter nutrients from the water around them. More importantly, contrary to fish, they do not require space or enrichment in order to grow, and their farmed habitat is similar to their wild habitat. They also often do not require much cooking, e.g. oysters are often eaten raw. However, this latter advantage leads to a historical issue in the shellfish industry: the product has a very short lifecyle. To ensure the product is safe for consumption, food safety programmes perform extensive testing on shellfish to detect human pathogens that could have accumulated from contamination of the water (since shellfish feed by filtering the water, pathogens such as Salmonella or norovirus can accumulate even if they are at low concentration in the water). The conventional testing procedures however are time-consuming and laborious, and require the access to sophisticated laboratory facilities. When the results of the test are finally obtained, the shellfish has been already consumed, which limits the implementation of any preventive action. This resulted in nearly 1 million cases of food poisoning in the UK in 2011, leading to about 11 million lost working days. In this project, we will develop and implement a low-cost technique, which has been developed for the detection of human and animal pathogens in low-resource settings, such as in the field in Uganda and in a farm in India, for the rapid detection of pathogens in seawater in aquaculture. Together with our partners the Centre for Environment, Fisheries and Aquaculture Sciences Cefas (the world leader in marine science and technology) and Cromarty Mussels Ltd (the largest single site for both mussel and oyster farming in Scotland), we will develop deployable paper-based biosensor devices (lab-on-a-paper) for the online monitoring of seawater and the detection of foodborne pathogens. The platform relies on the enrichment of pathogens from seawater using a combination of filtration and magnetic beads in a syringe, onto a paper-based biosensor. By folding the paper, in a process akin to origami, the genetic material of the pathogens is purified and distributed into specific areas, where nucleic acids are amplified. This amplification (performed using a small hand-held heater with low power at around 60C, but could also be performed in a thermos) is then detected using either direct visualisation of a color change or using a mobile phone for quantification, within 1h. Used in farms, the platform will allow the rapid detection of 3 pathogens, Salmonella and two types of norovirus, which are the most common pathogens associated with illness from shellfish consumption. Together with our partners, we will test the performance of the devices in the field in a shellfish farm, in Inverness. These results will then enable the consortium to progress towards developing this as a product for the industry to be able to rapidly respond to contamination events, so that consumer safety is assured, and shellfish aquaculture can grow to its full potential. Deployed within the environment, this platform also has the potential to serve as an early warning system of contamination events and to enable source disease tracking and thus risk prediction.

Phytoplankton (algae) are essential in marine ecosystems determining fisheries productivity however around 2% of marine phytoplankton species produce biotoxins that can accumulate in harvested shellfish, posing a threat to human health. Harvesting of shellfish, including mussels, scallops and oysters, is an important part of the UK aquaculture industry worth around £40 million per annum and supporting over 3,000 rural jobs. The harvested shellfish are an important source of protein with markets at home and abroad. There is significant potential to expand this industry, however, harvesting can be halted, particularly in the summer months, due to the presence of harmful algae in the sea which can accumulate in the filter feeding shellfish. Monitoring of water and shellfish for the presence of biotoxins helps determine if it is safe to harvest, and where closure occurs it has been reported to cost a single farm in excess of £160,000 per annum. This consortium brings together three new technologies and world class expertise to provide an early warning, near instant biotoxin detection and a system to protect harvesting sites during harmful algal events. This is a unique opportunity to exploit research three separate developments initially funded by RCUK, allowing their deployment to be expertly utilised through the direct collaboration of shellfish farmer, government regulators and trade associations. The first of the exciting new technologies is the e-mice, so called because although in a single small (6x12x6 cm) electronic instrument we aim to detect all groups of regulated biotoxins with the potential to include other biotoxins which may be regulated in the future. Not so long ago consumer safety was ensured by the use of a mouse bioassay, this has now been replaced by sophisticated analytical detection systems. Currently it takes around 1-week and multiple methods to obtain results however, the e-mice will be developed to provide a format that can be used at a shellfish harvesting site and give instant results supporting rapid management decisions regarding harvesting or protection of the shellfish grounds. Detecting toxicity once it has already accumulated can often limit the management options therefore this collaboration includes the satellite-based early warning system called ShellEye which will help predict harmful algae events and particularly their location with respects to shellfish harvesting areas. Data obtained from satellite imagery will be correlated with phytoplankton monitoring and biotoxin detection in phytoplankton samples. Early warning will then be used to make decisions on when to use the third of the innovative technologies which is the photocatalytic curtain. Also, pioneered under a different RCUK research project, the TiO2-based catalytic pods have specifically been designed to facilitate the treatment of biotoxins and algae in reservoirs in developing countries. The work planned here will explore their optimum configuration for use in a marine environment in a way that will protect harvesting sites, hence the concept of the reactive curtain. The benefits of using this technology is that no chemicals are discharged into the water, the catalyst when illuminated produces high energy, short life hydroxyl radicals which destroy organic molecules and can be active against microorganisms. The project will be underpinned by developing the capacity to produce all the required, phytoplankton, biotoxins and reference material to fully validate the e-mice during development and field use while also supporting photocatalytic optimisation. The culmination of the project will be the development of an integrated management strategy where all partners from industry, the regulators and academics will contribute to a practical close to real-time monitoring and protection of shellfish harvesting areas. This will in turn limit harvesting loses and ensure confidence to support expansion of this aquaculture industry.