As a proud Beijing citizen, I was appalled to learn that neighbourhood markets in the city are selling vegetables which are not only contaminated with chemical pesticides well in excess of Chinese standards, but are even worse affected than those sold in Shanghai markets. Indeed, while Shanghai's market food is hardly chemical-free, it contains lower levels of pesticides than both Beijing and Guangzhou, the other megacities covered in a Greenpeace East Asia investigation into the "Vegetables Basket Programme", a government initiative aimed at ensuring food security and safety standards.

Example of chemical products used in industrial agriculture. © GreenpeaceExample of chemical products used in industrial agriculture.

Besides intercity rivalries and Shanghai leading the race, the Greenpeace study released last week highlights the major food safety problem in Chinese megacities, which are failing to deliver healthy, good quality food to millions of people.

The reason behind Shanghai's better score is its investment in ecological farming, an innovative production model based on people, science and nature and not reliant on chemical input. Shanghai has also invested in food traceability systems that ensure more transparency about food production sources.

Ecological farm in the surroundings of Beijing. © GreenpeaceEcological farm in China.

The investigations sampled 133 vegetables of 26 varieties sold in Beijing, Shanghai and Guangzhou as well as their place of origin and tested them in an independent laboratory. For the first time in a Greenpeace investigation, GPS trackers were placed on the trucks transporting the vegetables to follow and track the entire supply chain to the three megacities.

In addition, a GoPro camera was attached to a cucumber, as our video shows, in order to follow its journey from field to market, but also symbolically show the miserable life of a chemically farmed vegetable. Within 80 days, over 30 different types of chemicals were sprayed on the cucumber to meet so-called ‘commercial standards' on how straight and hard a cucumber should be, and the presence of a fresh flower on top.

The lab testing results showed that vegetables collected in Beijing contained a mixture of pesticides, while more than one third of the vegetables in Guangzhou exceeded China's standard on maximum permitted residue. A cowpea sample from Guangzhou was found to have residues of omethoate, a toxic pesticide, 63 times the national safety standard. Shanghai came out top among the three cities with only one out of the 42 vegetables tested containing pesticide residues exceeding the national standard.

© Greenpeace

Although not perfect, the Shanghai model, based on ecological farming practices and better traceability systems, represents the right path and proof that an alternative system of food production is possible: a system that produces healthier and safer food for people but also avoids contaminating the planet with unnecessary chemical products like pesticides and fertilisers.

The ecological farming model needs to be scaled up in order to further improve the quality of Shanghai's food supply but also ensure that safe food can reach Chinese people living in other megacities and throughout China. This change towards an ecological food system is what a growing movement is demanding around the world. Politicians, companies and philanthropies need to respond to public demand by shifting agriculture investments and funds away from destructive chemical agriculture and towards modern ecological farming.

Jing Wang is an Ecological Farming Campaigner at Greenpeace East Asia.