POPs impact on human
health
The main distinction of POPs from the majority of
other pollutants is their ability to stay in the environment for many decades
and be transferred along food chains (water – algae – plankton – fish – humans;
soil – plants -�herbivorous animals –
humans). The principle source of human contamination with POPs is food, in
particular meat, fish, chicken eggs and dairy products. People who live or work
in close vicinity to POPs sources can have great exposure to POPs by breathing
them in.
Even small POPs concentrations have a genotoxic, immunotoxic and cancerous effects hence posing a real threat to health of the current and future generations. There is credible evidence that some POPs cause malignant tumors; neurological and psychiatric disorders, including weaker learning capabilities and negative personality changes; immune system disorders; reproductive and sexual disorders; reduction of lactation period and such diseases as endometriosis and diabetes, etc. For instance, dioxins can cause secondary immune deficiency, affect mental and physical development of humans, trigger mutation and toxication of genital glands and embryos. The main diseases caused by dioxins are chloracne and liver disorder. Some cases of changes of thyroid gland functions were observed in babies breastfed by mothers exposed to POPs. Dioxin exposure can reduce the lifespan.
POPs concentration in human
tissues and breast milk is of special concern. POPs is accumulated in embryos
through placenta and in babies through breast milk. Even super low
concentration of POPs (trillionth parts) can cause an irreversible damage to
brain and reproductive organs of a baby.
Pesticides pose the greatest threat to child health.
Many fruits and vegetables used for production of baby food such as apples,
pears, oranges and carrots contain pesticide residue. Lindane, a
hormone-destroying pesticide currently banned in Europe,
can still be found in some chocolates due to cocoa-beans imported from the
third-world countries where POP-based pesticides were extensively used in
agriculture. Lindane residue has also been found in milk, beef, cheese and
mushrooms in the last few years.
DDT (dichloro-diphenyl-trichloroethane) has adverse
and understudied effects on humans. This POP is accumulated in fatty tissues
but can be transferred with breast milk or break through placentary barrier.
DDT exposure can lead to hormonal and kidney disorders, diseases of central and
peripheral nervous systems, liver cirrhosis and chronic hepatitis.
Poly chlorinated biphenyls (PCBs) are the most common
POPs. PCBs are released into the environment as a result of evaporation from
plasticizers when burning household and industrial waste, as part of industrial
waste dumped in landfills and aerations fields. PCBs are accumulated in the
body, affect the endocrine system and sexual behavior, and cause developmental
defects in children and slow down their intellectual development. The adverse
effects on a woman and fetus start at the level of sex cells long before the
embryo and fetus development.
There is no doubt that environmental pollution has
major consequences for human health. Having realized this fact many developed
countries raised an issue on initiating the contamination elimination process.
About 60,000 out of hundreds of thousands of toxic organic compounds affect
living organisms, including humans. Twelve out of 60,000 most dangerous
chemicals were identified as persistent organic pollutants.�These twelve POPs were the initial subject
matter of the Stockholm Convention adopted in May 2001.