Pollution isn't just something that involves the air around us – it can have an impact on the food we eat too.
Take a look at the main culprits and where these can be found:
Dioxins are by-products of the manufacture of certain industrial chemicals and incineration or burning.
These substances are environmental contaminants that persist in the environment for many years and can find their way onto and into foods.
In fish, polluted water is the main cause of dioxin contamination while animals are mostly exposed to dioxins through the air. Dioxins settle on plants and feed, which are then eaten by animals. Dioxin concentrates in the fatty tissues of livestock and fish.
More than 90% of human exposure occurs mainly through foodstuffs. Those of animal origin normally account for approximately 80% of the overall exposure.
Other industrial pollutants include heavy metals such as mercury, lead and cadmium.
Fish are especially vulnerable to environmental pollutants because waters can become contaminated from industrial discharges or accidental spillage.
Recent reports of levels of mercury in large predatory fish such as swordfish have caused authorities in some countries to issue warnings that these fish should not be eaten by pregnant or lactating women or children due to the possibility of high levels of mercury.
Occasional intake by other consumers is not likely to pose a problem. However, intake should be limited to once a week.
The fishing industry has responded by harvesting smaller sized deep-sea fish, which are unlikely to have a build-up of heavy metals.
Source: The European Food Information Council (www.eufic.org)