Arsenic acid

Toxicity to terrestrial plants

Administrative data

Endpoint:

toxicity to terrestrial plants: long-term

Type of information:

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

Adequacy of study:

key study

Study period:

1998

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Well documented study even if no specific guideline was followed.

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Data source

Reference

Reference Type:

publication

Title:

Arsenic in wetland vegetation: Availability, phytotoxicity, uptake and effects on plant growth and nutrition

Author:

Carbonell A.A, Arabi M.A, DeLaune R.D, Gambrell R.P, Patrick Jr W.H

Year:

1998

Bibliographic source:

The Science of the Total Environment 217: 189-199

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Spartina alterniflora (dominant angiosperm of a large majority of regularly flooded salt marshes along the Atlantic and Gulf coasts of the United States) plants were grown in hydroponic culture containing different concentrations of As in a controlled environment for 30 days. Roots and shoots yields were determined on a wet weightnand dry weight basis.

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Arsenite

IUPAC Name:

Arsenite

Details on test material:

No details on test material

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
No details on properties of test surrogate or analogue material

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

No details

Test substrate

Vehicle:

no

Details on preparation and application of test substrate:

Hydroponic culture: 5% Hoagland nutrient solution(Hoagland DR and Arnon DI, 1950. The water-culture method for growing plnats without soil. California Agricultural Experimantal Station Circular 347: 1-32; McKee KI, 1996. Growth and physiological responses of neotropical mangrove seedlings to root zone hypoxia. Tree Physiology 16: 883-889)

Test organisms

Species:

other: Spartina alterniflora

Plant group:

Monocotyledonae (monocots)

Details on test organisms:

- Plant family: Angiospermae Monocotyledonae Poaceae
- Source of seed: Louisiana salt marsh

Study design

Test type:

other: growth parameters

Study type:

laboratory study

Substrate type:

other: Hoagland nutrient solution

Limit test:

no

Total exposure duration:

30 d

Post exposure observation period:

No post exposure observation period

Test conditions

Test temperature:

26 ± 2°C

pH:

no data

Moisture:

no data

Details on test conditions:

TEST SYSTEM
- Test container (type, material, size): hydroponic-plastic plots
- Amount of soil: 0.5L of 5% Hoagland nutrient solution
- Method of seeding:
- No. of seeds per container: 3
- No. of replicates per treatment group: 3
- No. of replicates per control: 3


NUTRIENT MEDIUM (if used)
- Description: Hoagland nutrient solution

GROWTH CONDITIONS
- Photoperiod: 16-h photoperiod
- Light source: photosynthetically active radiation (PAR) level of 350µmol m-2 s-1
- Light intensity and quality: no data
- Day/night temperatures: 26 ± 2°C
- Relative humidity (%): no data
- Water source/type: no data

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : growth parameters


TEST CONCENTRATIONS
- Spacing factor for test concentrations: 4
- Range finding study: no range-finding

Nominal and measured concentrations:

nominal concentrations: 0 (control), 0.2, 0.8 and 2.0 mg/L

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Effect concentrations 1

Species:

other: Spartina alterniflora

Duration:

30 d

Dose descriptor:

other: Effect concentration (inhibition)

Effect conc.:

2 other: mg/l culture medium

Nominal / measured:

nominal

Conc. based on:

element

Remarks:

As

Basis for effect:

growth

Effect concentrations 2

Species:

other: Spartina alterniflora

Duration:

30 d

Dose descriptor:

other: No effect concentration (inhibition)

Effect conc.:

0.8 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

element

Remarks:

As

Basis for effect:

growth

Results with reference substance (positive control):

No results with reference substance

Reported statistics and error estimates:

Statistical analyses were performed using the PROC GLM and PROC ANOVA procedures in Statistical Available System

Any other information on results incl. tables

The growth of Spartina alterna was increased at 0.2 mg/l.

Applicant's summary and conclusion

Validity criteria fulfilled:

not applicable

Conclusions:

The growth of Spartina alterna was inhibited at 2 mg As/l. There was no effect on growth at 0.8 mg/l and growth was stimulated at 0.2 mg/l, which are both considred as safe concentrations.

Executive summary:

In wetlands surface sediments of Louisiana, arsenic (As) concentrations are levated because of a wide use of inorganic arsenicals as cotton dessicants and of organic arsenicals as herbicides in rice-producing areas. Beside this, As levels are even higher in the region of produced water discharge associated with petroleum hydrocarbon recovery operations. The uptake, potential bioavailabilty and phytotoxicity of As to an important wetland species growing in the vicinity of produced water dischage sites, were studied. The effects caused by As chemical form and concentration on growth, tissue concentrations and distribution of As and nutrient elements were studied in Spartina alterniflora growing on hydroponic conditions. An experiment was conducted with treatments consisting of four As concentrations (0, 0.2, 0.8 and 2 mg As/l) as arsenite [As(III)]. An As level in the nutrient solution of 0.2 mg/l was safe or caused no toxic effects for this marsh grass (it did not reduced plant growth or interfere with plant nutrition). In fact, arsenite significantly increased total dry biomass production at an application rate of 0.2 mg/l.