Persistent organic pollutants (POPs) are a common term for the most hazardous organic compounds that negatively affect human health and environment. Transported through air and water they can have an effect on humans and nature far from those places where they have been used and were emitted into the atmosphere. They resist degradation for a long time and are able to accumulate and be passed through the food chain. 

Many POPs were widely used during the period of industrial expansion after the Second World War when thousands of synthetic chemicals were used for commercial purposes. Some of them turned out to be effective against insects and diseases in plant-growing and manufacturing industries. However, their effect on human health and environment turned out to be not so favorable.    

POPs include:

  1. Intentionally produced chemicals for their usage in agriculture, disease control, manufacturing and technological processes. They include PCBs (polychlorinated biphenyls) which were used in different devices (e.g. electrical transformers and large capacitors as the hydraulic liquids, refrigerants, additives to the paint and greasing) and DDTs (dichlorodiphenyl trichloroethane, dust) which are still used in several countries against mosquitoes that are the vectors of malaria;
  2. Unintentionally produced chemical (dioxins) which are evolved during some technological processes and incineration (e.g. during incineration of solid municipal and medical waste).

The definition appeared in the Stockholm convention which was adopted in 2001 and came into force in 2004 and it represents the international agreement which purpose is to protect human health and environment from persistent organic pollutants (POPs).

According to Stockholm convention the participating parties shall take the relevant measures for liquidation and reduction of:

- usage;

- producing;

- trade;

- POPs emission and storage.

Convention comprises the producing and usage of 21 pesticides as well as producing of the industrial chemicals and POPs that are unintentionally formed as the by-products during various industrial and chemical processes.

At the moment the Parties of the Stockholm convention are 180 countries and 152 countries of them have already ratified the Convention. The Convention is under the jurisdiction of United Nations Environment Programme (UNEP).

The Stockholm convention web-site