Benzenesulfonic acid, 4-C15-16-sec-alkyl derivs.

Toxicity to soil macroorganisms except arthropods

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

toxicity to soil macroorganisms except arthropods: short-term

Type of information:

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

Adequacy of study:

key study

Justification for type of information:

see read-across document

Reason / purpose for cross-reference:

read-across source

Key result

Duration:

21 d

Dose descriptor:

EC10

Effect conc.:

6.2 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Remarks on result:

other: E. albidus

Details on results:

. It should be noted that these studies report worst case exposures due to the use of a sandy test soil and the fact that LAS was added as an aqueous solution to the soil. In addition, too few replicates were used for the ECx approach (e.g., <5 controls) and several key deviations from draft protocols limited the reliability of endpoints for some studies (e.g., A. caliginosa and A. longa cocoon production). Nominal concentrations were derived from tables and figures since actual values were not found in the text.

The following table shows the results of all tests.  All values are nominal LAS concentrations in mg/kg dry weight.

Species	Parameter	NOEC	LOEC	LC10 or EC10	LC50 or EC50	Relia-bility Rating	Rationale for Reliability Rating
Enchytraeus albidus	Survival, adults Reproduction	198 20	397 40	194 6	430 41	1 1	Draft ISO/WD 16387 protocol
Aporrectodea caliginosa	Survival, adults Cocoon production Survival, juveniles Growth, juveniles	278 >793 >397 278	793 >793 >397 397	329 14 >397 105	535 129 >397 354	2 3 2 2	Comparable to ISO 11268-2 Deviations; limited cocoons Comparable to ISO 11268-2, but with only weight measurement
Aporrectodea longa	Survival, adults Cocoon production Survival, juveniles Growth, juveniles	278 >793 397 79	793 >793 793 278	329 27 296 84	535 137 517 349	2 3 2 2	Comparable to  ISO 11268-2 Deviations; limited cocoons Comparable to ISO 11268-2, but with only weight measurement
Folsomia fimetaria	Survival, adults Reproduction	>793 278	>793 278	>793 85	>793 424	1 1	Comparable to  ISO 11267
Hypogastrura assimilis	Reproduction	79	278	99	421	1	Comparable to  ISO 11267
Hypoaspis aculeifer	Survival, adults Reproduction	>793 278	>793 793	>793 82	>793 236	2 2	No guideline available

Validity criteria fulfilled:

yes

Conclusions:

The 21-day EC10 to E. albidus was 6.2 mg/kg dry weight.

Executive summary:

Adult E. albidus (10) were placed in soil containing the test substance for 21 days. The adults were removed, and the cocoons incubated in the soil for another 21 days. The juveniles were then counted. The 21-day EC10 to E. albidus was 6.2 mg/kg dry weight.

Reference 2

Endpoint:

toxicity to soil macroorganisms except arthropods: long-term

Type of information:

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

Adequacy of study:

key study

Justification for type of information:

see read-across document

Reason / purpose for cross-reference:

read-across source

Key result

Duration:

28 d

Dose descriptor:

EC10

Effect conc.:

46 mg/kg soil dw

Nominal / measured:

nominal

Basis for effect:

reproduction

Remarks on result:

other: A. caliginosa

Key result

Dose descriptor:

EC10

Effect conc.:

>= 120 mg/kg soil dw

Nominal / measured:

nominal

Basis for effect:

reproduction

Remarks on result:

other: E. crypticus

Details on results:

No toxicity to E. crypticus was seen at any dose level, including the highest dose level of 120 mg/kg soil. A dose-related inhibition of cocoon production was seen in A. caliginosa at the highest concentration of 150 mg/kg soil.

Validity criteria fulfilled:

yes

Conclusions:

The EC10 for A. caliginosa was 46 mg/kg soil. The EC10 for E. crypticus was >=120 mg/kg soil.

Executive summary:

Groups of A. caliginosa were exposed to soil containing 25 -150 mg/kg soil of LAS for 28 days. Groups of E. crypticus were exposed to concentrations of 0, 10, 40, 60, 80, 100, or 120 mg/kg soil (nominal). EC10 values based on reproduction were 46 mg/kg soil for A. caliginosa, and >= 120 mg/kg soil for E. crypticus.

Reference 3

Endpoint:

toxicity to soil macroorganisms except arthropods: short-term

Type of information:

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

Adequacy of study:

key study

Justification for type of information:

see read-across document

Reason / purpose for cross-reference:

read-across source

Key result

Duration:

14 d

Dose descriptor:

NOEC

Effect conc.:

250 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: body weight

Key result

Duration:

14 d

Dose descriptor:

LC50

Effect conc.:

> 1 000 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Key result

Duration:

14 d

Dose descriptor:

EC10

Effect conc.:

277 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: body weight

Remarks on result:

other: EC10 was not reported in original study report, but later calculated using study results using the method of Vanewijk, PH, and Hoekstra, JA, 1993. Calculation of the EC50 and its confidence interval when subtoxic stimulus is present. Ecotoxicol. Environ

Details on results:

There was 5% mortality at the 1000 mg/kg dw concentration on day 14. Body weight was decreased in the 500 and 1000 mg/kg dw groups by 23 and 33% respectively. The 1000 mg/kg dw group also showed lethargy and burrowing was also affected. Cocoon production was diminished in the 250 mg/kg dw group, and inhibited at higher concentrations.

Mortality and Weight Loss of Earthworms

Concentration	Number of			% Weight Loss
(mg/kg dw)	Day 0	Day 7	Day 14	Day 0-14
Control	40	40	40	14
63	40	40	40	5
125	40	40	40	6
250	40	40	40	5
500	40	40	40	23
1000	40	38	37	33

Validity criteria fulfilled:

yes

Conclusions:

The 14-day LC50 to earthworms was > 1000 mg/kg dw soil. The 14-day NOEC was 250 mg/kg dw soil.

Executive summary:

Groups of earthworms were exposed to concentrations of 0, 63, 125, 250, 500, and 1000 mg/kg dw for 14 days. The test animals were examined for mortality, behaviour, health, and reproduction on days 7 and 14. 5% mortality was seen at the highest concentration. Effects to health were seen at the 500 and 1000 mg/kg dw concentrations. The 14 -day LC50 was > 1000 mg/kg dw, and the NOEC was 250 mg/kg dw.

Description of key information

A series of studies have been conducted on soil macroorganisms using the read across substance LAS.

NOECs or EC10s for oligochaetes and arthropods varied from 27-250 and 41-320 mg/kg soil, respectively.

Key value for chemical safety assessment

Long-term EC10, LC10 or NOEC for soil macroorganisms:

71.7 mg/kg soil dw

Additional information

A series of studies have been conducted on soil macroorganisms using the read across substance LAS. The primary route of entry for the read across substance into the terrestrial environment is land application of sewage sludge intended as an amendment to agricultural lands. A large number of terrestrial ecotoxicology studies were reviewed by Jensen et al. (2007) to develop a European wide risk assessment of LAS in agricultural soils. Nine invertebrate species, three oligochaetes and six arthropods, have been evaluated in chronic toxicity to LAS in soil. Endpoints were all considered sensitive for these taxa. Only growth and reproduction endpoints were used in the PNEC derivation for soil. Effects on oligochaetes and arthropods were highly overlapping. NOECs or EC10s for oligochaetes and arthropods varied from 27-250 and 41-320 mg/kg soil, respectively. Key studies on the oligochaete Aporroectodea caliginosa and the springtail Folsomia fimeteria were conducted by Holmstrup and Krogh (1996) and Holmstrup et al. (2001) in several soil types including sand, loam and clay with varying dominant cations. A. calignosa had EC10s that ranged from 44-105 with a geometric mean of 71.7 mg/kg soil for the growth endpoint (most sensitive) and F. fimeteria had EC10s that ranged from 85-161 mg/kg soil for the reproduction endpoint (most sensitive).