EU criteria for risk assessment of persistance, bioaccumulation and toxicity of chemicals

GHS-pictogram-environment dangerA summary prepared by GreenFacts of the COMMISSION REGULATION (EU) No 253/2011  of 15 March 2011

This regulation is amending Regulation (EC) No 1907/2006 of the European Parliament and of the Council on the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) as regards Annex XIII

16.3.2011 Official Journal of the European Union L 69/7

1. The specific importance of persistance, bioaccumulative and toxic properties for managing risks

The identification of persistent, bioaccumulative and toxic properties of substances (PBT substances), and very persistent and very bioaccumulative substances (vPvB substances) is important in order to evaluate their intrinsic potential impact to affect human health and the environment and assess the real risks.

This is also the basis on which define regulatory rules regarding their use, substitution or ultimate ban, depending on each specific case (within the global EU chemicals Regulation or more specific Regulations such as the one on electric/electronic equipments (RoHS Regulation) .

To this end, the EU Commission redefined the approach to be applied within the EU for the identification of PBT substances and vPvB substances and  the EU  Regulation (EC) No 1907/2006 was amended accordingly. The revised aproach is based on a weight-of-evidence determination using expert judgement applied by comparing all relevant and available information.

Indeed, experience shows that, for the adequate identification of PBT and vPvB substances, all relevant information should be used in an integrated manner and applying a weight- of-evidence approach by comparing the information to the criteria set out.

2. What is a “weight –of-evidence approach” ?

The regulation states that a weight-of-evidence determination means that all available information bearing on the identification of a PBT or a vPvB substance is considered together, such as :

– the results of monitoring and modelling,

– suitable in vitro tests,

– relevant animal data,

– information from the application of the category approach (grouping, read-across), (Q)SAR results, see below) ,

– human experience such as occupational data and data from accident databases, epidemiological and clinical studies and well documented case reports and observations.

The quality and consistency of the data shall be given appropriate weight. The available results regardless of their individual conclusions shall be assembled together in a single weight-of-evidence determination.

A weight-of-evidence determination is particularly relevant in cases where the application of the classical and basic criteria set in the Regulation is not straightforward.

The identification shall also take account of the PBT/vPvB-properties of relevant individual constituents of a substance including their relevant transformation and/or degradation products and shall apply to all organic substances, including organo-metals.

3. How to gather the appropriate information on PTB properties.

In cases where the technical dossier contains, for one or more endpoints, only limited information, the Regulation says that the relevant information available in the technical dossier should be used for screening for P, B, or T properties. In order to avoid unnecessary studies, if there is no indication of the P or B properties from the screening registrants should not be required to develop additional information.

Only in cases where the screening assessment indicates a possible of P, B, or T property, or a vP or vB property, the registrant should develop additional information or propose additional testing to conclude its PBT and vPvB assessment, unless the registrant implements or recommends sufficient risk management measures or operational conditions.

Since substances can have one or more constituents with PBT or vPvB properties, or can transform or degrade into products with such properties, the Regulation specifies that the identification should also take account of the PBT/vPvB-properties of such constituents and transformation and/or degradation products.

Registrations of substances under Regulation (EC) No 1907/2006 that are not in accordance with the Annex to this Regulation shall be updated in order to comply with this Regulation no later than 19 March 2013.

4.  In brief : what are the criteria set by the Regulation for classification as PTB or vPvB


A substance fulfils the persistence criterion (P) or very bioaccumulable (vP) in any of the following situations:

the degradation half-life in marine water, fresh or estuarine water in marine sediment, in fresh or estuarine water sediment, in soil is higher thana priod comprised between 40 and 180 depending on the medium

4.2. Bioaccumulation

A substance fulfils the bioaccumulation criterion (B) when the bioconcentration factor in aquatic species is higher than 2 000.

A substance fulfils the “very bioaccumulative” criterion (vB) when the bioconcentration factor in aquatic species is higher than 5 000.

4.3. Toxicity

A substance fulfils the toxicity criterion (T) when either/and

–  the long-term no-observed effect concentration (NOEC) or low effect concentration (EC10) for marine or freshwater organisms is less than 0,01 mg/l;

– the substance meets the criteria for classification as carcinogenic, germ cell mutagenic or toxic for reproduction (“CMR”) according to Regulation EC No 1272/2008;

(c) there is other evidence of chronic toxicity, such as specific target organ toxicity after repeated exposure.

(see the original text of the regulation for more precise information)

5.  In brief : what  information is considered relavant for the assessment of PTB or  vP, vB properties

The following information shall be considered for screening for P, vP, B, vB and T properties :

5.1. Indication of (very) Persistant properties

(a) Results from tests on “ready” biodegradation or other screening tests (e.g. “enhanced ready test”, tests on inherent biodegradability) from theoretical evaluation using Quantitative Structure-activity relationships between molecules of the same kind ( (Q)SAR models or any other information provided that its suitability and reliability can be reasonably demonstrated.

5.2. Indication of (very) Bioaccumulative properties

The criteria is its octanol-water partitioning coefficient experimentally determined, estimated by (Q)SAR models.. . The partition of a molecule between octanol and water is a good indicator of its tendency to accumulate in lipidic media (memebranes, fat, …) Other information can be used provided that its suitability and reliability can be reasonably demonstrated : data on aquatic or terrestrial animals (inclmuding human data), chronic toxicity or rate of elimination from organisms (“toxicokinetics”),

5.3. Indication of Toxic properties

Aquatic toxicity in short term toxicity towards aquatic organisms towards microorganisms, algae (their growth inhibition), invertebrates (like microcrustacea), fish. Any other information can also be used in a “weight of evidence approach”  provided that its suitability and reliability can be reasonably demonstrated (in particular carcinogenic, mutagenic or reprotoxic (3CMR”) toxicity in terrestrial organisms such as insects,mammals or birds).

(see the original text of the regulation for more precise information)

note : the short summary reports published on the Blog of GreenFacts are not verified by its Scientific Board

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