July 29, 2020 — Two major global environmental issues are food contamination and waste disposal. Professor Wong Ming-hung, Advisor (Environmental Science), and Dr. Brian Man Yu-bon, Assistant Professor, at the Department of Science and Environmental Studies at The Education University of Hong Kong (EdUHK) have a solution for both.
Contamination and waste disposal are particularly relevant to Hong Kong, which ranks second in per capita seafood consumption in Asia and where, in 2018, over 1.5 kg of waste was sent to landfill sites each day. Eating fish and seafood has important health benefits. They are recognized by the Food and Agriculture Organization of the United Nations as being important for optimal brain and neurodevelopment in children, as well as lowering the risk of coronary heart disease among adults.
However, contamination can bring along health and environmental risks. This doesn’t merely come through polluted seas and rivers: it can also be present in the feed used in fish farms, which provide 47% of the fish on our plates. In response to rising fish feed production costs around the world, farmers look for alternative sources of feeds, such as trash fish, fishmeal, animal and grain by-products. Some also travel further afield to find lower prices, meaning longer transport and storage time. This can result in spoilage, as well as fungal and bacterial contamination. Added to that is mercury pollution, which because of human industrial activity is now 450% higher than natural levels, according to the United Nations Environment Program. The result is greater risk of contaminants causing fish to be poisoned, which can be transmitted to humans.
These factors, along with the equally important aim to help ease pressure on existing landfill sites, have led Professor Wong and Dr. Man to develop a cleaner, cheaper fish feed using food waste. “We started off with fish which were low in the food chain, such as grass carp and gray mullet,” explains Professor Wong. “They have lower nutritional requirements.” Initial work began on pellets for pond fish back in 2009, with funding from Hong Kong’s Environment and Conservation Fund, followed by a grant from the Innovation and Technology Fund in 2015 for pellets for inland fish.