Request for information on pentachlorophenol and its salts and esters


Information on transformation of pentachlorophenol to pentachloroanisole and proposal by Japan to fill information gaps


At its seventh meeting, the Committee examined the proposal by the European Union and its member States parties to the Stockholm Convention to list pentachlorophenol and its salts and esters in Annexes A, B and/or C to the Convention and applied the screening criteria specified in Annex D to the Convention.

The Committee agreed that pentachlorophenol alone did not meet the criteria set out in Annex D to the Convention but that its metabolite pentachloroanisole did. There was disagreement, however, as to whether the two chemicals should be jointly considered and moved to the Annex E evaluation stage, since pentachlorophenol could not be verified as the sole source of pentachloroanisole in the environment and there was uncertainty regarding the extent of transformation from pentachlorophenol and other possible precursors to pentachloroanisole and from the latter to pentachlorophenol.

The Committee agreed to defer its consideration of pentachlorophenol and its salts and esters until its eighth meeting and to include the draft decision on the substance in annex II to the present report, enclosed in square brackets to indicate a lack of consensus on certain items. It also agreed to establish an intersessional working group, with the mandate, among other things, to review studies on the fate and transport of pentachlorophenol and pentachloroanisole and to prepare material for consideration at the Committee’s eighth meeting.


  • Interested parties are invited to undertake the following activities and submit to the Secretariat the information on the outcomes:
    1. To initiate experiments under conditions relevant to the environment;.
    2. To collect monitoring data on pentachlorophenol and pentachloroanisole, in particular from pentachlorophenol-contaminated sites, as such data could provide information on what happens in the environment under actual conditions.
  • Such experiments and compilation of monitoring data should be initiated without delay so that they can be taken into account by the Committee at its eighth meeting.

Method of submission:

    Deadline for submission:

    • 31 July 2012

    If you have any questions regarding this request, please do not hesitate to contact Ms. Kei Ohno (e-mail:; telephone +41 22 917 8201).