Hydrocarbons, C4

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

migrated information: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

other information

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Peer reviewed data, from EU Risk assessment

Data source

Reference

Reference 1

Reference Type:

other: EU Risk Assessment

Title:

European Union Risk Assessment Report 1,3-BUTADIENE, CAS No: 106-99-0, EINECS No:203-450-8

Author:

[ECB] European Chemicals Bureau

Year:

2002

Bibliographic source:

published; It can be accessed through the Europa Server (http://europa.eu.int).

Reference 2

Reference Type:

publication

Title:

Predictions of the aquatic toxicity of high-productionvolume- chemicals.

Author:

Bol J, Verhaar HJM, van Leeuwen CJ, Hermens JLM

Year:

1993

Bibliographic source:

Part B: Predictions. Ministerie van Volkshuisvesting, Ruimtelijke Ordening en Milieubeheer, Report No. SVS 1993/9B.; cited in EU Risk assessment

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

QSAR and PNEC calculation for risk assessment

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Buta-1,3-diene

EC Number:

203-450-8

EC Name:

Buta-1,3-diene

Cas Number:

106-99-0

Molecular formula:

C4H6

IUPAC Name:

buta-1,3-diene

Details on test material:

- Name of test material: 1,3-BUTADIENE

Results and discussion

Effect concentrations

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

33.3 mg/L

Nominal / measured:

estimated

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: QSAR calculation

Any other information on results incl. tables

The TGD gives equations for estimating toxicity endpoints for various species. The following

toxicity data has been derived for 1,3-butadiene using a log Kow value of 1.99 and a molecular

weight of 54.09 g/mole. The equations used are thought to be suitable for non-polar narcotic

chemicals and it is thought that 1,3-butadiene is a member of this class of chemical (Bol et al.,

1993).

48h-EC50 for freshwater invertebrates (Daphnia magna) = 33.3 mg/l

16-day NOEC for fresh water invertebrates (Daphnia magna) reproduction/growth = 6.2 mg/l

From the aquatic toxicity results reported in EU Risk assessment it can be seen that data from structurally similar

compounds suggest that 1,3-butadiene may be slightly less toxic than might be expected from

QSAR predictions. Therefore, in the absence of experimental data for 1,3-butadiene it is

proposed to estimate the PNEC based on both the acute L(E)C50 QSAR predictions with an

assessment factor of 1,000 and the long-term NOEC QSAR predictions with an assessment

factor of 100. This approach gives a PNECwater of 32.6 µg/l from the acute QSAR data and 44

µg/l from the long-term NOEC QSAR data. As a conservative approach, the lower PNECwater of

32.6 µg/l will be used in the assessment.

The estimated PECregional is 0.073 µg/l giving a PEC/PNEC ratio of 0.002, again indicating low

concern.

It is expected that any 1,3-butadiene present in surface water will volatilise rapidly. Therefore,

even if 1,3-butadiene were released to surface water from point sources, the concentration would

be expected to decrease markedly with increasing distance from the source. Thus any potential

problems are likely to be associated with the area immediately downstream of a point source

discharge.