Persistent Organic Pollutants (POPs)

Persistent organic pollutants (POPs) are chemical substances that persist in the environment, bioaccumulate through the food web and pose a risk of causing adverse effects to human health and the environment. Because these substances are transported over long distances to regions where they have never been used or produced, the international community has repeatedly called for global action to reduce and eliminate their releases.

The Stockholm Convention

The Stockholm Convention on Persistent Organic Pollutants was adopted in 2001 and entered into force on 17 May 2004. It requires Parties to eliminate or restrict the production and use of listed POPs and to reduce releases of unintentionally produced POPs. The list of chemicals covered by the Convention has been expanded several times since the original “dirty dozen”.

Under Article 16 of the Convention, a Global Monitoring Plan collects comparable data on POP levels in core media such as ambient air and human milk or blood, so that the effectiveness of the Convention can be evaluated.

POPs Regulation in Türkiye

Türkiye signed the Stockholm Convention in 2001 and ratified it in 2009 (Approval Law No. 5871). The Convention is implemented through the Regulation on Persistent Organic Pollutants, published in Official Gazette No. 30595 of 14 November 2018 and amended on 25 March 2021. Its purpose is to protect human health and the environment from the adverse effects of persistent organic pollutants:

Annex 1: substances whose manufacture, placing on the market and use are prohibited
Annex 2: substances whose manufacture, placing on the market and use are restricted; manufacturers and importers report annually using the format in Annex 6
Annex 3: substances whose releases to air, water and soil must be inventoried and minimised
Annexes 4 and 5: wastes containing these substances, which must be destroyed or irreversibly transformed, and the applicable disposal and recovery operations
Annex 7: notification of stockpiles exceeding 50 kg

In the EU, persistent organic pollutants are regulated by Regulation (EU) 2019/1021. Collecting information from the supply chain on products and raw materials that may contain POPs, and keeping track of stockpiles, are key steps in compliance.

In Türkiye, a UNDP project on identifying and remediating POP-contaminated sites was implemented between November 2019 and July 2026.

Effects of POPs on Human Health and the Environment

The harmful effects of POPs on human health and the environment were not recognised until the 1960s, and the use of these compounds was encouraged until scientists gathered a large body of evidence linking POPs to damage to human health and the environment. The first evidence was population declines in wildlife: scientists observed a range of health effects in birds, fish and mammals. Wildlife species exposed to POPs may show effects such as:

People are exposed to POPs directly from the environment, at work and through the food chain. Some groups, such as farmers and workers, are exposed to POPs in their occupations. POPs are found in the blood, muscles and other tissues, especially fatty tissues, of the general population all over the world, and research on how POPs affect human health continues.

There is good evidence that human exposure to specific POPs or classes of POPs may cause the following effects:

The evidence suggests that women, infants and children are especially vulnerable to certain effects of POPs. POPs are transferred from mother to child both before and after birth, which can harm the developing infant.

For decades, awareness has grown of the toxic effects of chemicals that persist in the environment, travel great distances from their point of origin, bioaccumulate in humans and other organisms and become concentrated through food chains. Evidence of harmful effects at the population level shows that POPs are a threat to biodiversity and can even disrupt whole ecosystems.