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Deadly Diarrhoea Caused by Wastewater on Crops

The use of wastewater to irrigate vegetable crops in developing countries may significantly contribute to deadly health risks such as rotavirus.

The use of wastewater to irrigate vegetable crops, which is common across developing countries, may significantly contribute to deadly health risks such as rotavirus, a major cause of diarrhoeal diseases according to research published in Risk Analysis.

The research, which focused on the Beijing region, found that the risk posed to children eating vegetables grown with wastewater far exceeded the World Health Organization’s acceptable level.

Diarrhoeal disease is the second leading cause of death globally. More than 99% of deaths due to diarrhoeal disease occur in developing countries, and 90% of these are in children under five.

The research found that some vegetables posed greater risk than others. “This was due to leaf shape, which affects the amount of wastewater and contaminants that are retained,” said Dr Andrew Hamilton of The University of Melbourne’s School of Land and Environment. “Choy sum poses the greatest risk, while bok choy poses the least risk.”

The report recommended that China develop its own guidelines for wastewater use. “There is more wastewater irrigation in China than in the rest of the world combined,” Hamilton said. “Much of this is used growing vegetables.”

Hamilton explained that similar situations exist across Asia and other developing countries, and this is where the risk posed by diarrhoeal diseases is highest. “Vaccination programs for rotavirus are being rolled out globally, but at this stage they are far from reaching all children in developing countries,” Hamilton said.