Persistent organic pollutants (POPs) are harmful chemicals which travel rapidly, degrade slowly and are toxic to humans and wildlife. Some even refer to them as “silent killers”.
They are commonly found in pesticides, such as DDT, and industrial chemicals like polychlorinated biphenyls (PCB), as well as in unintentional by-products of industrial processes such as dioxins. These chemicals have been proven to cause a series of health problems from allergies to cancer, reproductive disorders and damage to the immune and nervous systems.
In China, as in many countries, a lack of knowledge among plant owners and limited national infrastructure or regulations to deal with the issue led to the unsafe storage of POPs pesticides, with waste often left in open containers in vacant buildings or other empty spaces located in built-up areas. As a result, toxic chemicals seeped into the soil and groundwater, while powdered chemicals also escaped over time into the air, posing a health risk. Solutions such as burning the pesticides created more pollution in the form of fly ash.
To reduce the global threat and eliminate the scourge of POPs, the international community created the Stockholm Convention which entered into force in May 2004. The United Nations Industrial Development Organization (UNIDO) supports countries to comply with their obligations under the Convention.