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Persistent organic pollutants (POPs)

POPs (Persistent Organic Pollutants) are internationally restricted, long-range compounds which are highly persistent and toxic and which easily accumulate in organisms. Most of these compounds are industrial chemicals, flame retardants or pesticides. Some are impurities of other chemicals or are inadvertently produced through processes such as combustion.
A white-tailed eagle in flight over the sea.
POPs are often fat-soluble and accumulate particularly in the organisms at the top of food chains, such as white-tailed sea eagles. © Adobe Stock

POPs are the most harmful environmental toxins, as they remain in the environment for a long time and can cause harm to humans and the environment even in low concentrations. They have been found to cause developmental and reproductive disorders in animals and can also affect people in the same way. The long-term and combined effects of these substances, however, are not yet known.

Mitigation of adverse effects through international cooperation

POPs travel far from their original sources of emissions, moving particularly towards polar regions. No country or region is able on their own to solve the environmental and health problems caused by POPs – international action is needed in order to limit them. POPs are restricted by two different treaties: the global Stockholm Convention and the UN Convention on Long-Range Transboundary Air Pollution, which is administered by the UN Economic Commission for Europe.

The Stockholm Convention

The 2001 Stockholm Convention either bans or severe restricts the production, trade, use and emissions of POPs. The convention entered into force in May 2004 and is one of the broadest environmental conventions. 186 countries (incl. the EU) have ratified the convention for at least the original list of 12 pollutants. Currently, the convention restricts the use of 31 substances and substance groups. However, not all parties have committed themselves to reducing the emissions of all the substances subsequently added to the agreement. Each party to the convention must draw up a plan for fulfilling their obligations.

The original agreement included a ‘dirty dozen’ of chemicals, which were mostly pesticides that were no longer in use:

  • aldrin
  • dieldrin
  • endrine
  • DDT
  • heptachlor
  • chlordane
  • mirex
  • toxaphene
  • hexachlorobenzene
  • PCB
  • dioxins
  • furans

The parties to the convention may propose, by means of an agreement, to restrict chemicals which can travel far from their emission sources and cause such significant environmental or health hazards that international restrictions are justified. The POP Review Committee (POPRC) evaluates proposals for new chemicals and, if necessary, proposes a restriction to the parties to the convention. Restrictions and permitted exceptional uses are agreed upon in negotiations between the parties (the Conference of the Parties / COP).

The following chemicals have been added to the Stockholm Convention since 2009:

  • lindane (HCH), added to the Stockholm Convention 2009
  • alpha- and beta-HCH (hexachlorocyclohexane), 2009
  • perfluorooctane sulfonic acid and its derivatives (PFOS), perfluorooctane sulfonyl fluoride (PFOSF) 2009
  • polybrominated diphenyl ethers (PBDE), 2009
  • penta- and octabromodiphenyl ether, 2009
  • hexabromobiphenyl (HBB), 2009
  • chlordecone, 2009
  • pentachlorobenzene (PeCB), 2009
  • endosulfan, 2011
  • hexabromocyclododecane (HBCD), 2013
  • pentachlorophenol PCP and its salts, 2015
  • hexachlorobutadiene HCBD, 2015
  • chlorinated naphthalenes CN, 2015
  • decabromodiphenyl ether DeBDE, 2017
  • short-chain chlorinated paraffins SCCP, 2017
  • perfluorooctanoic acid (PFOA), its salts, and similar compounds, 2019
  • dicofol, 2019
  • pefluorohexanoic acid (PFHxS), its salts, and similar compounds, 2022

The new restrictions enter into force when the parties ratify the amendments within their national legislation. In the European Union, the obligations of the Stockholm Convention are included in the POPs Regulation (EU) 2019/1021 (which repealed the old POPs Regulation (EC) 850/2004).

Regional UNECE Protocol on POPs

A Protocol on POPs was added in Aarhus in 1998 to the UN Convention on Long-Range Transboundary Air Pollution, which is administered by the UN Economic Commission for Europe (ECE). The Protocol on POP entered into force in October 2003 and currently has 29 signatories.

The revised protocol and the new restrictions entered into force in July 2012, when Commission Regulation (EC) No 519/2012 amended Commission Regulation (EC) No 850/2004. With the exception of PAHs, all other substances included in the Protocol are currently restricted by the Stockholm Convention.

EU regulation on the restriction of persistent organic pollutants (POPs Regulation)

The obligations of the Stockholm Convention and the UNECE Protocol on POPs have been incorporated into Regulation (EU) 2019/1021 of the European Parliament and of the Council on persistent organic pollutants (recast). The recast regulation repealed the old POPs Regulation (EC) 850/2004. The decree is valid as such in Finland and all EU countries and is the most important legislative instrument for restricting POPs.

According to the Chemicals Act, the competent authority of the POPs Regulation is the Finnish Environment Institute (Syke). Nevertheless, the competent authorities referred to in Article 7 concerning the management of waste containing POP compounds are the environmental permit authorities referred to in the Environmental Protection Act (527/2014). Market surveillance of POPs, meanwhile, is the responsibility of the Finnish Safety and Chemicals Agency (Tukes). Syke is responsible for monitoring and communicating the implementation of the POPs Regulation, and it engages in close cooperation with other authorities.

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Finnish Environment Institute (Syke)