Hydrocarbons, C10, aromatics, <1% naphthalene

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1993

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

The study was given a reliability rating of 1 because it followed a standard test guideline, which describes a procedure to evaluate this endpoint, and the results were reviewed for reliability and assessed as valid. The study was also conducted under GLP.

Justification for type of information:

A discussion and report on the read across strategy is given as an attachment in IUCLID Section 13.

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

yes

Vehicle:

no

Details on test solutions:

Individual treatment solutions were prepared as Water Accommodated Fractions (WAFs). This included adding test substance to glass vessels,
which contained dilution water and mixing for approximately 24 hours with a magnetic stirrer to produce a series of geometrically-spaced
loading rates (mg/L). After mixing, the WAFs were allowed to settle for an hour. Each aqueous phase was then drawn off and transferred to two
150 mL Erlenmeyer flasks which were completely filled. Two further flasks were filled with dilution water only and served as controls.

Test organisms (species):

Daphnia magna

Details on test organisms:

Organisms were supplied by in-house cultures. The laboratory culture is derived from a clone held at ICI Brixham Laboratory. The ICI clone was
itself obtained from the Institut de Recherche Chimique Applique (I.R.Ch.A.), France. Test organisms age = <24 hours old; parents age = 15 - 28
days.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

Water hardness of the control dilution water was 174 mg/L as CaCO3.

Test temperature:

Test temperature was 20 – 22 ºC.

pH:

The pH ranged from 7.7 to 8.1.

Dissolved oxygen:

Dissolved oxygen was 8.3 to 8.6 mg/L for "new" solutions and 8.6 to 8.7 mg/L for "old" solutions.

Salinity:

freshwater

Nominal and measured concentrations:

Nominal treatment levels were control, 0.1, 0.4, 1.0, 3.0 and 10 mg/L, which at t=0 measured non detected (< 2.5 mg/L), NA (not analyzed), NA, NA,
3.3 mg/L and 8.2 mg/L, respectively.

Details on test conditions:

Ten Daphnia magna, less than 24 h old, were added to each flask. The flasks were sealed with black caps that excluded air from the vessel. After
24 and 48 h the numbers of immobilized D.magna were recorded. D.magna were considered to be immobile, if, when the contents of the flask were
swirled they did not swim during a 15 second period of observation.

Photoperiod with a 16 h : 8 h light : dark lighting regime.

Reference substance (positive control):

no

Key result

Duration:

48 h

Dose descriptor:

EL50

Effect conc.:

>= 3 - <= 10 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

See Table in Remarks on Results

Reported statistics and error estimates:

Loading rates causing a 50% effect were determined by visual inspection of the data. They are expressed as being within a range bounded by loading rates that were tested. This is considered more appropriate for test materials that are mixtures of substances of different solubilities than is an interpolative statistical technique.

Nominal Loading	Measured Conc	Daphnia Immobilized
(mg/L)	(mg/L)	(@ 24, 48 hrs)*
Control	<LoD	0,0
0.1	<LoD	0, 0
0.4	<LoD	0, 0
1.0	<LoD	0, 0
3.0	3.3 – 3.1 **	0, 0
10.0	8.2 – 7.8 **	10, 10

*10 daphnids added to each of the control and treatment levels (both in duplicate) at test initiation

** Measured concentrations refer to the t=0h (fresh) and t=48 h (old) samples

Validity criteria fulfilled:

yes

Conclusions:

Water accommodated fractions of hydrocarbons, C10, aromatics, >1% naphthalene, produced a 48-hour LL50 value between 3 and 10 mg/L with Daphnia magna.

Executive summary:

Water accommodated fractions of hydrocarbons, C10, aromatics, >1% naphthalene, produced a 48-hour LL50 value between 3 and 10 mg/L with Daphnia magna.

Description of key information

There is no data available for Hydrocarbons, C10, aromatics, <1% naphthalene. However, data is available for a structural analogue, Hydrocarbons, C10 aromatics, >1% naphthalene and presented in the dossier. This data is read across to based on analogue read across and a discussion and report on the read across strategy is provided as an attachment in IUCLID Section 13.

Water accommodated fractions of hydrocarbons, C10, aromatics, >1% naphthalene, produced a 48-hour LL₅₀ value between 3 and 10 mg/L with Daphnia magna.

 

In a supporting study, water accommodated fractions of hydrocarbons, C10, aromatics, >1% naphthalene, produced a 48-hour LL₅₀ value of 10 mg/L with Daphnia magna.

Additional information

Water accommodated fractions of hydrocarbons, C10, aromatics, >1% naphthalene, produced a 48-hour LL₅₀ value between 3 and 10 mg/L with Daphnia magna.