SCHEER - Scientific Opinion on "Draft Environmental Quality Standards for Priority Substances under the Water Framework Directive" - Nonylphenol

SCHEER WG on Water Framework Directive
SCHEER members: Marian Scott (Chair), Marco Vighi (Rapporteur), Thomas Backhaus, Teresa Borges, Raquel Duarte Davidson, Peter Hoet, Pim de Voogt
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: 11 November 2022

For the draft dossier on Environmental Quality Standards on nonylphenol (revised from a previous dossier and EQS derivation of 2005), the SCHEER offers the following opinions:

The selected nonylphenol MAC QS offered in the dossier was derived using the deterministic approach to give a MAC QS_{fw eco} of 2.1 μg L^{- 1} and MAC QS_{sw eco} of 0.17 μg L^-1 which the SCHEER can support. The derivation of an AA QS for nonylphenol is complicated by the observation that linear and 4-tertiary isomers have very different endocrine disrupting properties. However, for regulatory purposes, it seems reasonable to assume all forms may be of the 4-tertiary variety to ensure that sufficiently protective QS are derived. Given the known vulnerability of certain groups to endocrine or reproduction related end-points, it was deemed appropriate to use the probabilistic approach with an SSD containing only 4 (particularly vulnerable) taxonomic groups. Following an AF of 5 to the HC5 of the SSD, this yielded an AA QS_{fw eco} of 0.037 μg L^-1 and AA-QS_{sw eco} of 0.0018 μg L^-1. The SCHEER can endorse these values.

Given the high Kow for nonylphenol, it was necessary to derive a benthic organism related QS. Using the deterministic approach and an AF of 10 to an EC10 for Lumbricus variegatus this generated an QS_{sediment fw} of 1.3 mg kg^-1_dw and QS_{sediment sw} of 260 μg kg^-1dw following an AF of 50, both of which the SCHEER can support.

To protect predators from secondary poisoning the dossier uses NOAEL data from a rat study to derive freshwater QS_{biota fw sec pois} of 2.2 mg kg^-1 for fish, QS_{biota fw sec pois} of 0.64 mg kg^-1 for bivalves, for marine QS_{biota sw sec pois} of 0.73 mg kg^-1 for fish, QS_{biota sw sec pois} of 0.15 mg kg^-1 for bivalves. Using a BCF multiplied by the default BMF this translated to a QS_{biota fw sec pois} of 0.85 μg L^-1 for fish, a QS_{biota fw sec pois} of 0.19 μg L^-1 for bivalves in the surrounding water and a QS_{biota sw sec pois} of 0.28 μg L^-1 for fish, a QS_{biota sw sec pois} of 0.043 μg L^-1 for bivalves in saltwater. The SCHEER accepts these secondary poisoning QSs with the exception one of the QS_{biota fw sec pois}, which it calculates should be 0.09 μg L^-1 for bivalves.

The dossier contains a QS_{biota hh} of 0.62 mg kg^-1 to protect human health with respect to fish consumption with an associated protective level of 0.28 μg L^-1 for fish in the water and 0.18 μg L^-1 for bivalves. The SCHEER is concerned there may have been an error in these calculations and so they cannot be endorsed yet. To protect human health from drinking water a QS_{dw hh} of 0.3 μg L^-1 already exists.

The AA-QS_{fw eco} of 0.037 μg L^-1 is the lowest most critical QS for the freshwaters. For marine waters the AA-QS_{sw eco} is 0.0018 μg L^-1, which is lower. Given the generally abundant dilution of the marine environment, the SCHEER considers the AA-QS_{fw eco} will be the more likely to be exceeded and this is the critical EQS.

Keywords:

Nonylphenol, 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 - nonylphenol, 11 November 2022.