Stockholm: People in developing countries are facing growing health risks by the widespread use of sewage to irrigate crops, according to a study unveiled on Monday at a global water conference in Sweden.
The report, by the International Water Management Institute, says more than half of farmland near 70% of cities in developing countries is watered with sewage.
“Irrigating with wastewater isn’t a rare practice limited to a few of the poorest countries,” said Liqa Raschid-Sally, a researcher at the institute. “It’s a widespread phenomenon, occurring on 20 million ha across the developing world, especially in Asian countries, like China, India and Vietnam, but also around nearly every city of sub-Saharan Africa and in many Latin American cities.” She was speaking on Sunday at the start of the World Water Week, a conference attended by 2,500 scientists, politicians and officials from 140 nations.
Experts said that 1.4 million children die every year from diarrhoea-related diseases and poor hygiene, and described the global sanitation crisis as “the world’s largest environmental problem”.
An increasing need for water has spurred the use of sewage to water crops but in many cases it is the only form of irrigation for farmers who lack clean water, the study showed. It is mostly used to produce vegetables and cereals.
However, the report said sewage also provides a livelihood for many by making possible the cultivation of land, and it recommends an increase in purifying water supplies rather than a total ban on the use of wastewater.
In Accra, Ghana, some 200,000 people depend on vegetables produced on agricultural land near the city which is watered with sewage, Raschid-Sally said. “That gives you an idea of the large potential of wastewater agriculture for both helping and hurting great numbers of urban consumers.”