Aluminum, benzoate C16-18 fatty acids complexes - high aluminium

Bioaccumulation: aquatic / sediment

Administrative data

Endpoint:

bioaccumulation in aquatic species: fish

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Non-GLP-compliant, non-guideline study, available as a published journal article. Limitations in design and/or reporting, but otherwise adequate for assessment. Acceptable with restrictions.

Justification for type of information:

The substance does not bioaccumulate, as it is rapidly hydrolysed. The organic hydrolysis products (benzoic acid and fatty acids) are readily biodegradable. Data is provided here on aluminium in fish.

Data source

Reference

Reference Type:

publication

Title:

Residue Dynamics and Effects of Aluminium on Growth and Mortality in Brook Trout

Author:

Cleveland L, Buckler DR and Brumbaugh WG

Year:

1991

Bibliographic source:

Environmental Toxicology and Chemistry, Vol. 100, pp 243-248

Materials and methods

Principles of method if other than guideline:

The steady state bioaccumulation factor of aluminium in brook trout Salvelinus fontinalis was determined under flow-through conditions at a fixed nominal concentration of 200 µg/L aluminium and at pH 5.3, 6.1 and 7.2.

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Aluminium sulfate

IUPAC Name:

Aluminium sulfate

Test material form:

other: stock solution

Details on test material:

- Name of test material (as cited in study report): Aluminium sulfate
- Physical state: Stock solution
- Analytical purity: Not reported

Radiolabelling:

no

Sampling and analysis

Details on sampling:

- Sampling intervals/frequency for test organisms: Five fish from each treatment collected on days 0, 3, 7, 14, 28 and 56 during exposure and duplicate or triplicate fish samples collected on days 3, 7, 14 and 28 during depuration.
- Sampling intervals/frequency for test medium samples: Sampled weekly during exposure period of 56 days.
- Sample storage conditions before analysis: Fish weighed and then frozen for later analysis. Test medium collected in 100 mL polyethylene bottle , acidified with nitric acid to a final concentration of 1% (v/v).
- Details on sampling and analysis of test organisms and test media samples (e.g. sample preparation, analytical methods):
Test organism: Fish with wet weights less than 3.4 g were pooled, predigested overnight in a glass pressure tube 5 mL with sub-boiled nitric acid. The samples were then vortexed and the sealed tubes heated in a water bath at 70 ºC for 48 hours to digest the sample. The cooled sampled was then diluted to 100 mL with reverse osmois water to produce a final sample containing 5% nitric acid. Fish samples with wet weights greater than 3.4 g were lyophilized and then homogenized before being treated as above.
Test medium: 100 mL samples from each treatment were acidified with distilled reagent-grade nitric acid to a final concentration of 1% (v/v).

Test solutions

Vehicle:

no

Details on preparation of test solutions, spiked fish food or sediment:

PREPARATION OF SPIKED WATER
- Details of spiking: Proportional diluter delivery appropriate amounts of aluminiium sulphate stock solution and acid (1/3 nitric acid and 2/3 sulphuric acid) to glass aquaria (length 52 cm x width 32 cm x height 30.5 cm) equipped with 20.5 cm standpipes and containing 34.1 litre of solution. The diluter delivered one litre of exposure water to each aquarium every 15 minutes (2.8 volume replacement per day).
- Controls: Test medium only (fish analysed at day 0 only).
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): Not applicable

Test organisms

Test organisms (species):

Salvelinus fontinalis

Details on test organisms:

TEST ORGANISM
- Common name: Brook trout
- Source: Eyed eggs obtained from Beity's Resort, Valley, Washington.
- Age at study initiation (mean and range, SD): 30 days
- Length at study initiation (length definition, mean, range and SD): Not reported
- Weight at study initiation (mean and range, SD): 0.2 g
- Weight at termination (mean and range, SD): 0.24 to 1.50 g
- Method of breeding: Fish cultured from eyed eggs in well water (alkalinity 250 mg/L and hardness 270 mg/L as CaCO3) at 17 to 18 ºC until they were about 30 days old.
- Health status: Not reported
- Description of housing/holding area: Glass aquaria (length 52 cm x width 32 cm x height 30.5 cm)
- Feeding during test: Yes
- Food type: Rangen commercial feed
- Amount: Ad libitum
- Frequency: Twice daily

ACCLIMATION
- Acclimation period: Three days
- Acclimation conditions (same as test or not) : Yes
- Type and amount of food: Not reported
- Feeding frequency: Not reported
- Health during acclimation (any mortality observed): Not reported

Study design

Route of exposure:

aqueous

Test type:

flow-through

Water / sediment media type:

natural water: freshwater

Total exposure / uptake duration:

56 d

Total depuration duration:

28 d

Test conditions

Hardness:

Alkalinity 236-244 µeq/L

Test temperature:

12 ºC

pH:

Treatment 1: 5.3 (SD = 0.5)
Treatment 2: 6.1 (SD = 0.3)
Treatment 3: 7.2 (SD = 0.1)

Dissolved oxygen:

Not reported

TOC:

Not reported

Salinity:

Not applicable

Details on test conditions:

TEST SYSTEM
- Test vessel: Glass aquaria
- Type (delete if not applicable): Open
- Material, size, headspace, fill volume: Length 52 cm x width 32 cm x height 30.5 cm equipped with 20.5 cm standpipes and containing 34.1 litre of solution.
- Aeration: No details given
- Type of flow-through (e.g. peristaltic or proportional diluter): Proportional diluter
- Renewal rate of test solution (frequency/flow rate): One litre every 15 minutes (2.8 volume replacements per day)
- No. of organisms per vessel: 100 (at start)
- No. of vessels per concentration (replicates): 2
- No. of vessels per control / vehicle control (replicates): None

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Well water
- Alkalinity: 236 - 244 µeq/L
- Holding medium different from test medium: Yes. See above
- Intervals of water quality measurement: pH measured daily
- Intervals of test medium replacement: Flow-throught system. 2.8 volume replacements per day.

OTHER TEST CONDITIONS
- Adjustment of pH: Yes by proportional controller using nitric (1/3) and sulphuric (2/3) acid mixtures.
- Photoperiod: Not reported
- Light intensity: Not reorted

Nominal and measured concentrations:

Nominal concentration 200 µg/L at nominally three pH's 5.3, 6.1 and 7.2.
Measured values: Treatment 1: 251.5 to 198.1 µg/L at nominal pH 5.3. Treatment 2: 323.5 to 211.9 µg/L at nominal pH 6.1. Treatment 3: 415.0 to 253.6 µg/L at nominal pH 7.2.

Reference substance (positive control):

no

Details on estimation of bioconcentration:

The BIOFAC computer program of Blau and Agin was used to derive uptake and clearance rate constants , biological half-lives, bioconcentration factors (BCF) and the time to 90% steady state for aluminium in whole-body tissues.

Reference: Blau GE, Agin GL (1978). A user's manual for BIOFAC: A computer program for characterizing the rate of uptake and clearance of chemicals in aquatic organisms. Central research, physical research and math applications The Dow Chemical Company, Midland, MI, USA.

Results and discussion

Bioaccumulation factor

Bioaccumulation factor 1

Type:

BCF

Value:

215 dimensionless

Basis:

whole body w.w.

Calculation basis:

steady state

Remarks on result:

other: Optimal estimated value at pH 5.3. Linearized standard deviation 90.

Remarks:

Conc.in environment / dose:200 µg/L aluminium

Bioaccumulation factor 2

Type:

BCF

Value:

123 dimensionless

Basis:

whole body w.w.

Calculation basis:

steady state

Remarks on result:

other: Optimal estimated value at pH 6.1. Linearized standard deviation 54.

Remarks:

Conc.in environment / dose:200 µg/L aluminium

Bioaccumulation factor 3

Type:

BCF

Value:

36 dimensionless

Basis:

whole body w.w.

Calculation basis:

steady state

Remarks on result:

other: Optimal estimated value at pH 7.2. Linearized standard deviation 20.

Remarks:

Conc.in environment / dose:200 µg/L aluminium

Depuration

Depuration 1

Elimination:

yes

Parameter:

DT50

Depuration time (DT):

0.46 d

Depuration 2

Elimination:

yes

Parameter:

DT50

Depuration time (DT):

1.26 d

Depuration 3

Elimination:

yes

Parameter:

DT50

Depuration time (DT):

0.52 d

Details on kinetic parameters:

- Uptake rate constant (k1): 352 (SD = 102)/d at pH 5.3, 68 (SD = 21)/d at pH 6.1 and 49 (SD = 20) at pH 7.2.
- Depuration (loss) rate constant (k2): 1.5 (SD = 0.41)/d at pH 5.3, 55 (SD = 0.17)/d at pH 6.1 and 1.34 (SD = 0.50) at pH 7.2.
_ Biological half-life: 0.46 (SD = 0.12) days at pH 5.3: 1; 1.26 (SD = 0.39) days at pH 6.1; and 0.52 (SD = 0.19) at pH 7.2.
- Computation / data analysis: Days to 90% steady state: 1.53 (SD = 0.42) days at pH 5.3, 4.17 (SD = 1.31) days at pH 6.1 and 1.72 (SD = 0.64) days at pH 7.2.

Metabolites:

No data

Results with reference substance (positive control):

Not applicable

Details on results:

- Mortality of test organisms: At pH 5.3: 2.0 % (day 3), 11.5 % (day 7), 21.0 % (day 14), 42.5 % (day 28) and 73.0 % (day 56). At pH 6.1: 0.0 % (day 3), 0.0 % (day 7), 3.5 % (day 14), 27.5 % (day 28) and 48.0 % (day 56). At pH 7.2: 0.0 % (day 3), 0.0 % (day 7), 0.0 % (day 14), 0.0 % (day 28) and 1.0 % (day 56).
- Observations on body length and weight: The weight of fish exposed to aluminium at pHs 5.3 and 6.1 did not differ significantly throughout the exposure periods. Except for day 3, all fish exposed to aluminium at pH 7.2 had significantly higher weights than the fish exposed to the lower pHs.

Reported statistics:

ANOVA was used to statistically analyse percentage mortality (arcsine transformed values), fish weight and whole-body residues of aluminium. Least significant difference (LSD) tests were used to determine significant differences between paramater means. The two-compartment model of Blau et al (Blau GE, Neely WB, Branson DR (1975). Ecokinetics: A study of the fate and distribution of chemicals in laboratory ecosystems. Am. Inst. Chem. Eng. J. 21: 854-861) was used to determine the residue dynamics of aluminium in whole-body tissues at each test treatment.
Mortality measured daily.

Any other information on results incl. tables

During the exposure the measured pHs were close to the nominal values. The measured concentrations were initially higher than the nominal value (200 µg/L aluminium) but gradually approached the expected value.

Background concentrations of aluminium average 0.68 µg/g for fish from the laboratory culture. Aluminium concentrations in fish during exposure ranged from 2.8 to 78 µg/g and during depuration ranged from 0.7 to 5.3 µg/g

The maximum observed BCF were 232 at pH 5.3, 153 at pH 6.1 and 46 at pH 7.2. The results clearly show that aluminium uptake and absorption by brook trout decreases markedly at higher pHs.

During the depuration period all fish eliminated aluminium very quickly and by day 3 all fish contained less than 5 µg/g.

Mortality was significantly higher for fish exposed to aluminium at pH 5.3, except at day 56 when mortality at pHs 5.3 and 6.1 were not significantly different. Mortality of brook trout exposed to aluminium at pH 7. was less than 3 %.

Applicant's summary and conclusion

Validity criteria fulfilled:

not applicable

Conclusions:

The bioconcentration factor of aluminium in the fish species, Salvelinus fontinalis is 215 at pH 5.3, 123 at pH 6.1 and 36 at pH 7.2.

Executive summary:

The bioconcentration factor of aluminium in the fish species,Salvelinus fontinalis is 215 at pH 5.3, 123 at pH 6.1 and 36 at pH 7.2.The bioconcentration factor was determined in a non-GLP, non-guideline study published in a peer-reviewed journal (Cleveland et al 1991).The study measured the uptake of aluminium in Salvelinus fontinalis under flow-through conditions at a fixed nominal concentration of 200 µg/L aluminium and at three pHs, 5.3, 6.1 and 7.2.There are limitations in design and/or reporting, but the study follows sound scientific principles and is considered reliable and relevant for use for this endpoint.