Grown on waste

 
Last Updated: Saturday 04 July 2015

Down to Earth Use of wastewater in urban agriculture is critical to farmers' income and food security but raises health risks

Down to Earth In the face of growing water scarcity, use of wastewater in agriculture has become inevitable in urban areas of developing countries

Down to Earth Though only treated wastewater should be used in agriculture, in absence of adequate infrastructure, farmers in poorer cities use raw or partially-treated wastewater.This can cause infectious diseses

Down to Earth In 70 per cent cities,s ome amount of industrial effluents are also found mixed with it

Not-so-clean crop  
Water sources, quality and methods used in wastewater agriculture
Down to Earth
Down to Earth 200 million farmers across the world use such highly-contaminated water to irrigate 20 million hectare (ha) of land.In developing countries, over 1.1 million farmers follow this practice to make a living from 0.4 million ha of land

Down to Earth These farmers, in urban and peri-urban areas, help ensure an immediate supply of perishable food to cities, primarily fresh vegetables.They also cultivate cereals and fodder

Down to Earth They access wastewater easily and free of cost.Some 43 per cent) believe it is a vital source of plant nutrients and save on fertilizers

Down to Earth Farmers (in 38 per cent cities) are aware that using wastewater in agriculture poses health risks both for them and consumers, but in the absence of alternative source of irrigation, they have no choice

Down to EarthMost developing countries (54 per cent) have no guidelines to regulate the use of wastewater in agriculture.Eight countries have their own guidelines while another four follow guidelines set by the fao or the who

Down to Earth Even in these 12 countries, enforcement of regulations and monitoring rarely happen.The bans are mostly on wastewater use in cultivation of vegetables that are eaten uncooked

Down to Earth Consumers want to avoid wastewater produce.But most of them (90 per cent) have no way of knowing the origin.Hence, they end up consuming produces grown on wastewater

Source Comprehensive assessment of water management in agriculture, a survey report by International Water Management Institute. The survey was done in 53 cities in developing nations

Health risks
  • Exposure to a variety of pathogens can cause skin irritation and gastro-intestinal disorders among farmers
  • The pathogens and other chemicals like heavy metals from industrial effluents also contaminate crops and thus affect those who consume it
 
All that we eat
Distribution of crop types grown with wastewater
Type of crop Number of cities
Africa Asia Latin America Middle-East
Vegetables 8 16 7 1
Cereals 5 15 5 2
Fodder 1 5 3 0
Other 1 5 3 2

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