One of the challenges for all of us living in Shanghai is the fact that food production standards are notoriously unregulated, meaning that we can't trust the food and water we
consume to be safe. As China lacks independent testing facilities and transparent regulation of food production, there is little reliable data about food- and water
Fortunately and perhaps surprisingly, acute food poisoning has a relatively low incidence in Shanghai, mainly due to government monitoring of the hygiene standards in restaurants,
markets and supermarkets. Agricultural production is a different matter however being far less well-regulated, with much of the soil in China being contaminated by heavy metals. This
leads to widely varying amounts of pesticides and other toxic substances present in our food depending on the kind and origin of the product. While pesticides in food may not have acute
effects, they are stored in the body and may cause problems with health after years of intake. In particular the effects of pesticide mixtures cannot be predicted.
Which contaminants do we find in food/water and what do they do to our body?
POPs (persistent organic pollutants) - POPs are highly stable chemicals which accumulate in food chains for long periods of time, most notably pesticides, flame
retardants and plasticizers. Long-term consumption may result in cancer, high blood pressure, asthma, Parkinson´s like diseases, infertility, shortened lactation, endometriosis, genital
malformation, peripheral nerve damage, and dysfunctional immune systems
Heavy metals - Lead, cadmium, mercury, zinc and arsenic are some of the heavy metals found in food. They are stored in the body and remain there for long periods of time and
may predispose to later problems such as deficits in attention, memory, learning and IQ, "soft" bones and kidney damage
Microbes - processing, storage, transport and packaging of food needs high hygienic standards, otherwise contamination by a variety of microbes is possible. Tap water
and water from dispensers can also be a source of unwanted bacterial or other types of contamination
Medication/antibiotics - meat, dairy products and eggs often contain residues of antibiotic medication which are routinely used (and overused) in modern animal husbandry and
farming practices. Long term intake may predispose to hormone system dysfunctions and antibiotic resistance
Where do the contaminants come from?
Agriculture - lacking proper education in farming practices, farmers in China often use 3-4 times more fertilizers and pesticides than necessary (in average 10
kg/ha, compared to 2.3 kg/ha in Germany) and apply them too often and too close to harvest. Some of the chemicals used are banned or restricted in other countries.
Industrial processes - many harmful substances such as dioxins and furans are produced unintentionally, for example during production of paper and
plastics or by burning processes. They migrate into the air, water and soil and thus enter the food chain
Traffic - cars are a major source of toxic gases and particles, especially when they lack modern filters
Mining - during mining heavy metals like lead, cadmium, mercury and others are released into the environment and enter the soil, waterways and ultimately the ground
Waste - private households and industry all produce waste which contains toxic material such as batteries, disinfectants and packaging. In addition many pollutants
are produced after burning waste, particularly waste containing plastics, solvents and petroleum products
Usually safe (green) and most likely to be contaminated (red) food items