Food contamination is happening all the time, everywhere. Whether from the water used to irrigate the crops or the air polluted from nearby factories, or simply through contact with toxic chemicals, pollution of our sources of nourishment is easy and, most often, invisible. Some of the most common contaminants are explained below.
Organophosphates, organoarsenicals etc. get into the food through the common agricultural practice of spreading pesticides. While they may prevent the destruction of food by parasites, some of the sprayed pesticides will leak into the soil and may be taken up through the roots of plants. Thus, food pollution by pesticides is a real problem everywhere in the world. Pesticides may cause various medical conditions, from gastrointestinal to nervous system problems.
Perchlorate gets into the environment through a series of human activities (involving military operations, rocket research, firework displays, and other activities implying explosive materials, as well as many industries using perchlorate salts) as well as natural formation in arid climates. Chile and California are areas with confirmed natural formation of perchlorate, and other areas of the world (especially those with arid climate) may contain it too. Perchlorate may cause metabolism disruption by affecting the normal function of the thyroid. This is because perchlorate has a similar structure with iodine and may displace iodine binding to the thyroid gland and ultimately impairing its normal functioning. Perchlorate was reported in a series of foods, including lettuce and milk.
Organo-mercurial compounds (organic compounds of mercury) have a strong tendency to bioaccumulate in living organisms such as fish. The death and poisoning of many people in Japan in the 1970’s (the Minamoto incident) alerted the world to how heavy consumption of fish grown in mercury-contaminated water can lead to serious medical problems. Mercury can get into the water from remote areas, as it is easily transported by air over long distances (mercury is the only metal that is also found in gaseous form).
Benzene is a natural constituent of crude oil, a flammable, easily evaporated, and colorless liquid that constitutes a basic petrochemical substance (it is, in fact, present in gasoline and other petrol byproducts), and is also used in hundreds of other products, from rubber to detergents and pesticides. Its presence was reported in a series of soft drinks. Benzene is a proven human carcinogen and is often linked to several types of leukemia and anemia.
Along with pesticides, polychlorinated biphenyl ethers have reached even remote arctic areas via air and water – these are persistent organic food pollutants that may bioaccumulate in fat tissues of living organisms, such as fish. They are anthropogenic chemicals virtually omnipresent in contemporary life, used in pigments and dyes, in plastic and rubber products, in insulating equipment etc. They are known to cause cancer in animals, and very likely to cause cancers, endocrine diseases, and neurotoxicity in humans.