SCHEER - Scientific Opinion on Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (DL-PCBs)

SCHEER WG on Water Framework Directive
SCHEER members: Marian Scott (Chair), Marco Vighi (Rapporteur), Thomas Backhaus, Teresa Borges, Peter Hoet, Pim de Voogt, Rodica Mariana Ion
External experts: Andrew Johnson, Jan Linders
Contact: SANTE-SCHEERec [dot] europa [dot] eu (SANTE-SCHEER[at]ec[dot]europa[dot]eu)
On request from: European Commission
Adopted on: 24 January 2023

The dossier on Environmental Quality Standards for “Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (DL-PCBs)” is reviewed by the SCHEER according to the general mandate on EQS dossiers.

In the dossier only the biota sections (7.2 and 7.3) have been revised. However, the SCHEER recommends that section 7.1 (QS for water and sediments) should also be revised.

The SCHEER endorses the QS_{biota, secpois, fw} = 3.0 x 10^-4 μg WHO₂₀₀₅ TEQ kg_ww^-1 for fish.

Due to the difficulties for defining a unique BMF value the QS_{biota, secpois, sw} was not calculated. The SCHEER is of the opinion that at least a provisional/precautionary QS_{biota,secpois,sw} should be proposed.

The SCHEER endorses the QS_{biota, hh, food} = 35 pg WHO₂₀₀₅ TEQ kg_biota^-1.

The SCHEER agrees with the calculated value of QS_{dw, hh} = 2.0 pg L^-1 but disagrees with the conclusion of the dossier of not using this value as a standard due to the lipophilic properties of dioxin-like compounds.

Considering that the QS for water and sediment and for drinking water were not derived, the most critical EQS cannot be indicated by the SCHEER.

Finally, it is the opinion of the SCHEER that the QS_{biota, hh food} should be adopted instead of the existing EU food limit for dioxin-like compounds.

Keywords:

Dioxins, Water Framework Directive, environmental quality standards

Opinion to be cited as:

SCHEER (Scientific Committee on Health, Environmental and Emerging Risks), Final Opinion on Draft Environmental Quality Standards for Priority Substances under the Water Framework Directive", Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (DL-PCBs), 24 January 2023.