2,3-dichloroaniline

Toxicity to aquatic algae and cyanobacteria

Administrative data

Endpoint:

effects on growth of an additional algal species

Type of information:

experimental study

Adequacy of study:

other information

Study period:

2022

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: No reliability is given as this is an applicant's summary entry for a variety of studies.

Data source

Reference

Reference 1

Reference Type:

publication

Title:

A comparative study of the toxicity of 1,1,2-trichloroethane, Dieldrin, Pentachlorophenol and 3,4-dichloroaniline for marine and fresh water organisms

Author:

Adema DMM, Vink GJ

Year:

1981

Bibliographic source:

Chemosphere Vol. 10, No. 6, 533-554

Reference 2

Reference Type:

other: secondary source

Title:

3,4-dichloroaniline (3,4-DCA)

Author:

EU-Risk Assessment Report

Year:

2006

Bibliographic source:

EUR 22235 EN; ISSN 1018-5593

Reference 3

Reference Type:

review article or handbook

Title:

2,4-Dichloranilin; 2,5-Dichloranilin; 3,4-Dichloranilin

Author:

Beratergremium für umweltrelevante Altstoffe (BUA)

Year:

1994

Bibliographic source:

Wissenschaftliche Verlagsgesellschaft, BUA report 140

Reference 4

Reference Type:

publication

Title:

Consecutive system of tests for assessment of the effects of chemical agents in the aquatic environment

Author:

Adema D.M.M., Kuiper J., Hanstveit A.O., Canton H.H.

Year:

1982

Bibliographic source:

Pestic. Chem. 3, 537-544

Reference 5

Reference Type:

other: Expert Statement

Title:

2,3-dichloroaniline (CAS 608-27-5) Read-across justification

Year:

2022

Materials and methods

Principles of method if other than guideline:

TNO (1980): Degradability, Ecotoxicity and Bioaccumulation; The determination of the possible effects of chemicals and wastes on the aquatic environment. Government Publishing Office, The Hague, The Netherlands.

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

2,3-dichloroaniline

EC Number:

210-157-9

EC Name:

2,3-dichloroaniline

Cas Number:

608-27-5

Molecular formula:

C6H5Cl2N

IUPAC Name:

2,3-dichloroaniline

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

Sampling method: concentration of the test compound was measured by chemical analysis during the test and was at least 70% of the nominal value

Test organisms

Test organisms (species):

other: various algae species; Phaeodactylum tricornutum, Chlorella pyrenoidosa and Scenedesmus quadrlcauda

Study design

Water media type:

other: Phaeodactylum tricornutum: enriched seawater. Chlorella pyrenoidosa, Scenedesmus quadrlcauda: enriched freshwater

Total exposure duration:

96 h

Test conditions

pH:

the pH was measured during the test and was always about 8

Dissolved oxygen:

the oxygen concentration was measured during the test and was never less than 70% of the saturation value

Nominal and measured concentrations:

measured concentration was at least 70% of the nominal value

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

96 h

Dose descriptor:

EC50

Remarks:

growth on Scenedesmus quadrlcauda

Effect conc.:

2.2 mg/L

Effect concentrations 2

Duration:

96 h

Dose descriptor:

EC50

Remarks:

growth on Chlorella pyrenoidosa

Effect conc.:

3.2 mg/L

Effect concentrations 3

Duration:

96 h

Dose descriptor:

EC50

Remarks:

growth on Phaeodactylum tricornutum

Effect conc.:

0.45 mg/L

Any other information on results incl. tables

Read across (3,4-dichloroaniline):

Test was done according to OECD Guideline 201 on Scenedesmus pannonicus in fresh water static test for 96hours.  There was a constant light, test temperature was 20°C. 

EC50 (algea, 96h, growth rate): 4.8 mg/L (Adema et al.., 1982; cited in EU RAR, 2006; cited in Wissenschaftliche Verlagsgesellschaft, BUA report 140, 1994)
NOEC (algae, 96h, growth rate): 1 mg/L (Adema et al., 1982; cited in EU RAR, 2006; cited in Wissenschaftliche Verlagsgesellschaft, BUA report 140, 1994)

TNO (1980): dutch guideline according to Adema, 1980 (similar to OECD 201), static, salt-water, 15°C, 96h, diatom Phaeodactylum tricornutum
EC50(96h) 0.45 mg/L (also cited in EU RAR, 2006; cited in Wissenschaftliche Verlagsgesellschaft, BUA report 140, 1994)

Applicant's summary and conclusion

Conclusions:

Test was done on Phaeodactylum tricornutum, Chlorella pyrenoidosa and Scenedesmus quadrlcauda for 96 hours. EC50 value on growth rate is 0.45 mg/L, 3.2 mg/L and 2.2 mg/L respectively.

Executive summary:

In this read-across approach data on 3,4-dichloroaniline (CAS 95-76-1, source substance) is used to fill data gaps for 2,3-dichloroaniline (CAS 608-27-5, target substance). According to the “Read-Across Assessment Framework” (RAAF) (ECHA 2017) the analogue approach is followed. Data on 3,4-dichloroaniline (CAS 95-76-1) is used to fill data gaps for 2,3-dichloroaniline (CAS 608-27-5). The target substance is basically an isomer of the source substance. The physical and chemical properties of the source and the target substance are in the same range. Both, the source and the target substance have a log Pow value of less than 3, which implies a low potential to bioaccumulation. Thus, the source and the target substance may be excreted quickly and are not expected to bioaccumulate in the food chain. However, 3,4-dichloroaniline has shown significant ecotoxicity based on tests done on fish, daphnids and algae. Hence, based on the structural similarity, the similar physico-chemical properties, and the fact that the structural difference in the source substance indicates a slightly higher toxicity when compared to the target substance, the target substance as such does not need to be tested in aqueous system. It is sufficient for hazard assessment to use the data gained with 3,4-dichloroaniline. This can be regarded as worst-case for the target substance. For more details please see attached read-across statement.