Salicylic acid

Toxicity to soil macroorganisms except arthropods

Administrative data

Endpoint:

toxicity to soil macroorganisms except arthropods: long-term

Type of information:

experimental study

Adequacy of study:

other information

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

other: Although conducted with pure test substance, the method used is far from the guidelines (mortality after 6 weeks exposure, more than one worm per vial, substrate not characterised...)

Data source

Reference

Reference Type:

publication

Title:

Effect of aromatic compounds, humic acids and lignins on growth of the earthworm Eisenia foetida.

Author:

Hartenstein R.

Year:

1982

Bibliographic source:

Soil Biol. Biochem. 14 : 595-599

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

E. foetida hatchlings were exposed to a sludge substrate containing different concentrations in salicylic acid.
The impact on growth and on mortality of the test substance was recorded every two weeks during 6 weeks and at the end of the test (6weeks) respectively .

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Salicylic acid

EC Number:

200-712-3

EC Name:

Salicylic acid

Cas Number:

69-72-7

Molecular formula:

C7H6O3

IUPAC Name:

2-hydroxybenzoic acid

Details on test material:

Test compound was purchased from Aldrich Chemical Co, Milwaukee, WI (USA).

Sampling and analysis

Analytical monitoring:

not specified

Test substrate

Vehicle:

not specified

Details on preparation and application of test substrate:

The test substances were processed for assay by mixing 0.01, 0.1, 0.5 or 1.0 g or mL into 100 g sludge 
Assuming exactly 13% solids in the sludge, the substances were thus tested at concentrations of about 0, 0.1, 1.0, 4 and 8 % (w/w) dry weight.
About 30g spiked sludge (average 13% solids) was placed over a 4 mm depth of silt loam in a 20*100 mm petri dish.

Test organisms

Test organisms (species):

Eisenia fetida

Details on test organisms:

Stock culture of Eisenia foetida were maintained on horse manure or activated sludge.
Two hatchlings of 10 mg live weight were used for the experiment

Study design

Study type:

laboratory study

Substrate type:

other: sludge

Total exposure duration:

6 wk

Remarks:

measurements after 2, 4 and 6 wks

Post exposure observation period:

No post exposure period

Test conditions

Test temperature:

24+-1°C.

pH:

no data

Moisture:

No exact data. Sludge contained 11 to 15% of solids, placed on silt loam layer.

Details on test conditions:

TEST SYSTEM
- Test container (material, size): petri dish of size 20 x 100 mm
- Amount of soil or substrate: About 30 g sludge (ca 13% solids) with test substance were placed over a ca 4 mm depth of silt loam in a 20*100 mm Petri dish. 
- No. of organisms per container (treatment): Two hatchlings, each under 10 mg live weight, were added. 
- No. of replicates per treatment group: 5 replicates 
- No. of replicates per control: 5

SOURCE AND PROPERTIES OF SUBSTRATE
- Composition (if artificial substrate): sludge which contained 11-15% solids. 
- Maximum water holding capacity (in % dry weigth): no data
- Stability and homogeneity of test material in the medium: solids are not homogeneously distributed in sludge, and solid concentration varies from sludge sample to sample and withn a single sample with time due to microbial activity

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
Growth was checked every 2 weeks and worms were transferred to freshly prepared substance at 4 weeks. 
Growth achieved at 2 or 4 and 6 weeks was determined by rinsing the worms in distilled water, blotting and weighing. 
Mortality was determined by enumeration and said to be significant if 5 or more earthworms died.

TEST CONCENTRATIONS
- 5 concentrations tested

Nominal and measured concentrations:

Assuming exactly 13% solids in the sludge, the substances were thus tested at concentrations of about 0, 0.1, 1.0, 4 and 8 % (w/w) dry weight.

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

6 wk

Dose descriptor:

LC100

Effect conc.:

1 other: % dw of salicylic acid / sludge

Nominal / measured:

not specified

Conc. based on:

test mat.

Basis for effect:

mortality

Effect concentrations 2

Duration:

6 wk

Dose descriptor:

LOEC

Effect conc.:

< 1 other: % dw of salicylic acid /sludge

Nominal / measured:

not specified

Conc. based on:

test mat.

Basis for effect:

growth

Details on results:

Salicylic acid inhibited the growth at concentrations < 1% and gave 100% mortality at 1%.
Hatchlings in control dishes would gain more than 500 mg in 6 weeks. An average weight of 582 mg +/- 85 SD, with a cv of 14.6% was attained by controls in 6 wks in 45 similar assays during 16 months. This reflects both variation in earthworm growth and sludge quality. Mortality in controls was less than 2%.

Results with reference substance (positive control):

no data

Reported statistics and error estimates:

Weight at 6 weeks was evaluated by analysis of variance.
Significant differences were determined by the Neuman-Keul test
Mortality was said to be significant if 5 or more earthworms died.

Applicant's summary and conclusion

Validity criteria fulfilled:

not applicable

Remarks:

no guideline followed