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Contaminants

Traces of fertilisers or pesticides used in producing food can remain as contaminants. For example, dangerously high levels of the poisonous metal cadmium have occasionally been found in Australian bread. The cadmium came from rock phosphate fertilizer that was sprayed onto the wheat fields.

Insects consume one third of the food we grow and store. Some farmers protect their crops from insects by spraying with pesticides. Early pesticides like DDT were later found to accumulate in animals and in the environment and are no longer used. Modern pesticides are designed so they quickly break into safer chemicals and do not accumulate.

Organic food is produced without the use of manufactured pesticides and using only natural fertilisers such as compost.

What does organic mean?
Organic can mean many different things. In its broadest sense it means relating to living things. It has a more specific meaning when talking about organic food or organic chemistry.

Organic food is produced using natural fertilizers such as compost rather than manufactured ones and without the use of manufactured pesiticides. Within the organic food industry different organisations have different standards that must be met for products to be called organic.

Organic chemistry is the chemistry of substances containing carbon compounds. The earliest carbon compounds studied came from living organisms but chemists can now make a range of organic chemicals. Some of these are not naturally found in living organisms.

Advertisers often describe products as organic because people usually think organic means natural and good for you. However, the product being advertised may be organic because it contains carbon compounds but still be neither natural nor good for you. Some naturally occurring organic chemicals can also be poisonous.


Agricultural spraying
magnifyChemical control of weeds


Organic flours
magnifyOrganic flour products
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