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Endpoint:
sediment toxicity: long-term
Type of information:
experimental study
Adequacy of study:
weight of evidence
Study period:
12/2011
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: GLP comparable to guideline study
Qualifier:
equivalent or similar to
Guideline:
other: Newman, J.P., Jr. (1975). The effects of heavy metals on the asexual reproduction of the annelid Aeolosoma headleyi Beddard (1888). M.S. thesis. Virginia Polytechnic Institute and State University, Blacksburg, V.A.
Qualifier:
equivalent or similar to
Guideline:
other: Niederlehner, B.R., Buikema, A.L., Jr., Pittinger, C.A., and Cairns, J., Jr. (1984). Effects of cadmium on the population size of a benthic invertebrate Aeolosoma headleyi (Oligochaeta): Environmental Toxicology and Chemistry 2, 255-262.
GLP compliance:
yes
Specific details on test material used for the study:
Details on properties of test surrogate or analogue material (migrated information):
/
Analytical monitoring:
yes
Details on sampling:
- Analytical samples from each treatment were collected

- Sampling method:

TOTAL ALUMINUM
“New” waters were taken directly from the beaker using a 20 mL syringe after the 3-hour equilibrium period. Approximately 5 mL was drawn into the syringe to rinse the inside of the syringe and then expunged. Then 15 mL of sample was drawn into the syringe and injected into a 15 mL polypropylene conical tube. Samples of “old” waters were taken from a composite of each replicate from each concentration. “Old” water was pulled off from the top half/layer of the water column within each test chamber.

DISSOLVED ALUMINUM
Approximately 20 mL was drawn into the syringe of which 5 mL was pushed through the filter to waste and the remaining 15 mL was collected into a 15-mL polypropylene conical test tube.

MONOMERIC ALUMINUM
Following collection of a sample for dissolved aluminum analysis, the same filter was used to filter approximately 15 mL aliquots for monomeric aluminum analysis. Due to reduced sample volumes, no monomeric metals samples were taken from “old” waters.

- Sample storage conditions before analysis:

TOTAL AND DISSOLVED ALUMINUM:Samples were then preserved with trace metal grade nitric acid (AR-ACS grade, Mallinckrodt Chemical, Hazelwood, MO, USA) to pH < 2 and refrigerated (0 - 4 °C) prior to analysis.

MONOMERIC ALUMINUM:Samples were immediately analyzed for monomeric Al content.
Vehicle:
no
Details on sediment and application:
PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method:
A stock solution of 1000 mg Al/L was prepared by addition of 6.96 grams of Al(NO3)3·9H2O to 500 mL of Milli-Q water in a volumetric flask. The stock solution was then stored in a plastic container in the dark at 0 - 4°C. The pH of the 1000 mg Al/L stock solution was measured at 3.6 - 3.8. All concentrations within this report are expressed as micrograms Al per liter (μg/L Al).
Test concentrations were prepared by adding the appropriate volume of stock solution (1000 mg/L Al) to the dilution (reconstituted) water. A volumetric flask was filled to approximately 80% of its capacity with dilution water. Next, the aluminum stock solution was added to the volumetric flask to achieve the desired nominal concentration. The volume was then completed to 250 mL with the dilution water. The pH was checked and adjusted to a pH of 6.0 using dilute HCl or NaOH, as appropriate. The waters were placed in an enclosed box (injected with a pre-determined percent volume (2.3 – 2.6%) of CO2) for 3 hours equilibration period in an environmental chamber at test temperature.
Test organisms (species):
other: Aeolosoma sp.
Details on test organisms:
TEST ORGANISM
- Justification for species other than prescribed by test guideline:Use of this test organism qualifies as a level of organization (Phylum) not otherwise represented as part of the minimum taxonomic requirements for calculation of a predicted no effect concentration (PNEC) for the freshwater aquatic compartment, within the context of a species sensitivity distribution (SSD) approach (European Commission 2003). The choice of Aeolosoma sp. as a testing species was based upon its commercial availability and its inclusion in the latest update to the USEPA’s cadmium ambient water quality criteria.
- Source: Carolina Biological Supply (Burlington, NC, USA).
- Feeding during test: yes
- Food type:nfusoria (slurry made from 3-5 rabbit pellets [Animal House, Corvallis, OR, USA]
- Amount:200 μL Infusoria in 300-400 mL control/dilution water)

Study type:
laboratory study
Test type:
semi-static
Water media type:
freshwater
Limit test:
no
Duration:
17 d
Post exposure observation period:
/
Hardness:
48 mg/L as CaCO3
Test temperature:
25± 2°C
pH:
5.9-6.1
Dissolved oxygen:
/
Salinity:
/
Ammonia:
/
Conductivity:
/
Nominal and measured concentrations:
nominal concentrations: 0, 100, 500, 1000, 2000, 4000 μg/L
Average measured total Al concentrations: 0.5, 84.5, 480.6, 962.5, 2156.9, 4460.6 μg/L
Details on test conditions:
TEST SYSTEM
- Test vessel:six-well polystyrene culture plates
- Type (delete if not applicable): closed
- Material, size, headspace, fill volume:polystyrene, 100.2 mL filled with test solution
- Renewal rate of test solution (frequency/flow rate): Water renewals on a Monday, Wednesday, Friday
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates):4
- No. of vessels per control (replicates):4

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: The dilution/ control water used in the toxicity test was soft reconstituted laboratory water prepared by adding the appropriate reagent grade salts (CaSO4, MgSO4, KCl, and NaHCO3; USEPA 2002) to Milli-Q water to achieve the desired nominal hardness and alkalinity values of 50 and 30 mg/L as CaCO3, respectively. Reconstituted water was prepared as detailed in standard USEPA methods (USEPA 2002). Two batches of reconstituted laboratory water were used for the duration of the study.
- Chlorine:<0.05mg/L
- Alkalinity: 8mg/L as CaCo3
- Ca/mg ratio: 2.72
- DOC: <0.50mg/L
- Ammonia: <1.0mg/L
- Calcium: 12.5 mg/L
- Magnesium: 4.6mg/L
- Sodium: 13.3mg/L
- Chloride: 14.7mg/L
- Sulfate: 48.7mg/L
- Intervals of water quality measurement: Certain water quality parameters (i.e., temperature, dissolved oxygen [DO], and pH) were measured in each concentration at test initiation, at renewal, (in both freshly prepared renewal waters and old waters), and at test termination. Conductivity was also measured in the freshly-prepared renewal water at test initiation and renewal.

OTHER TEST CONDITIONS
- Adjustment of pH:The pH was checked and adjusted to a pH of 6.0 using dilute HCl or NaOH, as appropriate.
- Photoperiod:6:8 hour light:dark cycle
- Light intensity:cool-white fluorescent lights at ~50 foot candles.

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
Observations of the number of organisms were made on days 3, 5, 7, 10, 12, 14, and 17. On those days, organisms were counted and transferred from their old chambers into newly- prepared test chambers. No observations regarding the different stages of pygidial budding occurred during the test and the total of all organisms at test termination were used in the summary of total population size.
Reference substance (positive control):
no
Duration:
17 d
Dose descriptor:
NOEC
Effect conc.:
962.5 µg/L
Nominal / measured:
meas. (arithm. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
other: population size
Duration:
17 d
Dose descriptor:
LOEC
Effect conc.:
2 156.9 µg/L
Nominal / measured:
meas. (arithm. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
other: population size
Duration:
17 d
Dose descriptor:
EC10
Effect conc.:
987.9 µg/L
Nominal / measured:
meas. (arithm. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
other: population size
Remarks on result:
other: CL: 336.6 - 2899.4 µg/L
Duration:
17 d
Dose descriptor:
other: EC20
Effect conc.:
1 235.1 µg/L
Nominal / measured:
meas. (arithm. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
other: growth rate
Remarks on result:
other: CL: 649.7 - 2347.9 µg/L
Duration:
17 d
Dose descriptor:
EC50
Effect conc.:
1 923.9 µg/L
Nominal / measured:
meas. (arithm. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
other: population size
Remarks on result:
other: CL: 1368.1 - 2705.3 µg/l
Details on results:
/
Results with reference substance (positive control):
/
Reported statistics and error estimates:
STATISTICAL ANALYSIS
Statistical analysis was performed using measured average total Al concentrations of newly prepared solutions. Differences in the population sizes at test termination were evaluated using statistical computer packages (Comprehensive Environmental Toxicity Information System [CETIS], Tidepool Scientific Software, McKinleyville, CA, USA and Toxicity Relationship Analysis Program [TRAP], Duluth, MN, USA). If the data met the assumptions of normality and homogeneity, the no-observable effect concentration (NOEC) and lowest- observable effect concentration (LOEC) were estimated using an analysis of variance to compare (p = 0.05) organism performance in the experimental treatments with that observed in the control. The effective concentrations to reduce population size by 10%, 20%, or 50% relative to control performance (EC10/EC20/EC50) were estimated using threshold sigmoid regression analysis. Exposure concentrations were log-transformed before determination of the EC10, EC20, and EC50 values.

Table: Population size data

 Average Total Aluminum (μg/l)  Average population (± Std Dev)
 0.5 65.3 ± 5.3 
84.5  66.0 ± 13.8
480.6  78.3 ± 9.2 
962.5  65.0 ± 15.9 
2156.9  27.5 ± 6.8 
4460.6   3.3 ± 2.6
Conclusions:
Total measured exposure concentrations ranged from 0.5 to 4461 μg Al/L and resulted in a significant effect on organism population growth at the highest two treatments. The study resulted in a no observable effect concentration [NOEC] of 963 μg/L total Al and a lowest observable effect concentration [LOEC] of 2157 μg/L total Al for growth. The effective concentrations to reduce growth by 10% and 20% relative to control performance (EC10 and EC20 with 95% confidence intervals) was 988 (337 – 2899) and 1235 (650 – 2348) μg/L total Al, respectively.
Executive summary:

As part of an environmental program designed to provide data for the setting of water quality standards, data describing the chronic toxicity of aluminum to a variety of aquatic organisms are needed. Aluminum toxicity is a function of the chemical species of aluminum present in the water and this speciation is a function of the physico/chemical properties (e.g., pH, temperature, hardness) of the water. Much of the existing aluminum toxicity data was conducted under “acid” water conditions (pH 4.5-5.5); therefore, efforts are underway to develop data describing the chronic toxicity of aluminum to aquatic organisms at hydrogen ion concentrations (i.e., pH) typical of natural environmental conditions. The study reported herein determines the chronic toxicity of aluminum, at a pH of 6.0, to an aquatic oligochaete, Aeolosoma sp. Aeolosoma sp. is a representative of family Oligochaeta. Use of this test organism qualifies as a level of organization (Phylum) not currently represented in the species sensitivity distribution used in the derivation of a predicted no effect concentration (PNEC) for the freshwater aquatic compartment, within the context of a species sensitivity distribution approach (European Commission 2003). In this study, Aeolosoma sp. were exposed to a series of aluminum concentrations for seventeen days, starting as < 24 hour old organisms. To allow for possible changes in aluminum speciation, exposure solutions were aged for a 3-hour equilibrium period prior to organism exposure. Nominal test concentrations ranged from 0 to 4000 μg Al/L and total, dissolved, and monomeric aluminum were measured at test initiation. As the formation of insoluble chemical species was apparent through low dissolved and monomeric measurements (all concentrations measuring below 10 μg Al/L), total Al was used to interpret the biological data in this study. Total measured exposure concentrations ranged from 1 to 4461 μg Al/L and resulted in a significant effect on organism population growth at the highest two treatments. The study resulted in a no observable effect concentration [NOEC] of 963 μg/L total Al and a lowest observable effect concentration [LOEC] of 2157 μg/L total Al for growth. The effective concentrations to reduce growth by 10% and 20% relative to control performance (EC10 and EC20 with 95% confidence intervals) was 988 (337 – 2899) and 1235 (650 – 2348) μg/L total Al, respectively.

Endpoint:
sediment toxicity: long-term
Type of information:
read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
weight of evidence
Justification for type of information:
REPORTING FORMAT FOR THE ANALOGUE APPROACH
[Further information is included as attachment to Iuclid section 13]
Reason / purpose:
read-across source
Reason / purpose:
read-across: supporting information
Duration:
10 d
Dose descriptor:
NOEC
Effect conc.:
4 281.8 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
mortality
Duration:
28 d
Dose descriptor:
NOEC
Effect conc.:
4 281.8 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
mortality
Duration:
10 d
Dose descriptor:
NOEC
Effect conc.:
1 100.2 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
growth rate
Remarks:
Ash free dry weight
Duration:
28 d
Dose descriptor:
NOEC
Effect conc.:
4 281.8 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
reproduction
Duration:
10 d
Dose descriptor:
LOEC
Effect conc.:
> 4 281.8 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
mortality
Duration:
28 d
Dose descriptor:
LOEC
Effect conc.:
> 4 281.8 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
mortality
Duration:
10 d
Dose descriptor:
LOEC
Effect conc.:
2 132.7 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
growth rate
Remarks:
Ash free dry weight
Duration:
28 d
Dose descriptor:
LOEC
Effect conc.:
> 4 281.8 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
reproduction
Duration:
10 d
Dose descriptor:
EC10
Effect conc.:
2 923 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
mortality
Remarks on result:
other: CL: 857-0.9997.0 µg/L
Duration:
10 d
Dose descriptor:
EC10
Effect conc.:
971.6 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
growth rate
Remarks:
Ash free dry weight
Remarks on result:
other: CL:220.8-4276.0 µg/L
Duration:
28 d
Dose descriptor:
EC10
Effect conc.:
1 271.5 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
reproduction
Remarks on result:
other: CL: 134.7 - 14715.5 µg/l
Duration:
10 d
Dose descriptor:
other: EC20
Effect conc.:
4 691 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
mortality
Remarks on result:
other: CL:547-10191.0 µg/L
Duration:
10 d
Dose descriptor:
other: EC20
Effect conc.:
1 933.2 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
growth rate
Remarks:
Ash free dry weight
Duration:
28 d
Dose descriptor:
other: EC20
Effect conc.:
3 387 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
reproduction
Remarks on result:
other: CL: 1010.0 - 13438.0 µg/L
Details on results:
/
Results with reference substance (positive control):
/
Reported statistics and error estimates:
STATISTICAL ANALYSIS
Statistical analysis was performed using measured average total Al concentrations. Differences in survival (at Day 10), growth (at Day 10), adult emergence, and reproduction (as number of eggs per egg case) were evaluated using a statistical computer package (Comprehensive Environmental Toxicity Information System [CETIS], Tidepool Scientific Software, McKinleyville, CA, USA and Toxicity Relationship Analysis Program [TRAP], Duluth, MN, USA). If the data met the assumptions of normality and homogeneity, the NOEC and LOEC were estimated using an analysis of variance to compare (p = 0.05) organism performance in the experimental treatments with that observed in the control. The effective concentrations to reduce survival, growth, or reproduction by 10% or 20% relative to control performance (EC10/EC20) were estimated using threshold sigmoid regression analysis. Exposure concentrations were log-transformed before determination of the EC10 and EC20 values. Initial parameters input into the TRAP database for logIC50, Y-intercept, and steepness were: 4.2, 335.0, and 0.50, respectively.

Table 1: Summary of total metal analyses (µg/L Al)

 Nominal conc.  Total Aluminum         
   Total average  Total Std Dev  Total average  Total Std Dev
   with day 0     without day 0   
 0  7.5*  -  7.5*  -
 312.5  233.0  136.3  254.2  136.1
 625  490.4  144.5  527.0  122.4
 1250  1100.2  295.9  1184.0  230.3
 2500  2132.7  436.4  2282.3  255.7
 5000  4281.8  752.5  4568.2  294.5

* For calculation of average concentrations, the control water has been given a value of 7.5 μg/L Al (half the detection limit).

Table 2: Summary of dissolved metal analysis (µg/L Al)

 Nominal conc.  Dissolved Al (µg/L)   
   Dissolved average*  Dissolved Std Dev
 0  <15  -
 312.5  <15  -
 625  <15  -
 1250  28  26
 2500  21  15
 5000  17  21

* For average and standard deviation determinations, samples with values below the detection limit (< 15) are given a value of 7.5 ug/L Al (half the detection limit).

Table 3: Summary of monomeric metal analyses (µg/L Al)

 Nominal conc.  Monomeric aluminum (µg/L)   
  Monomeric average*   Monomeric Std Dev
 0  < 10.8  -
 312.5  < 10.8  3.1
 625  < 10.8  3.8
 1250  < 10.8  4.1
2500   14.8  6.4
 5000  38.2  17.5

* For average and standard deviation determinations, samples with values below the detection limit (< 10.8) are given a value of 5.4 ug/L Al (half the detection limit).

Table 4: Survival

 Average measured total Al conc. (µg/L) Proportion survided (±SD) 1  
   Day 10  Day 28 (as adult emergence)
 7.5  0.8500 ± 0.06383  0.6833 ± 0.1168
 233.0  0.9333 ± 0.07698  0.7667 ± 0.1182
 490.4  0.8333 ± 0.1388  0.6833 ± 0.1944
 1100.2 0.8667 ± 0.1089   0.8583 ± 0.09718
 2132.7  0.8333 ± 0.08607  0.7167 ± 0.1054
 4281.8 0.7167 ± 0.2396   0.6167 ± 0.1543
     

1 Survival is reported as the average survival within a treatment (combination of all replicates within a treatment).

SD = Standard Deviation

Table 5: Organism growth data - Ash free dry weight1

 Average measured total Al concentration (µg/L)  Ash free dry weight (average weight per surviving organism) (in mg ± SD))
 7.5  1.149 ± 0.1199
 233  1.118 ± 0.1064
 490.4  1.279 ± 0.2599
 1100.2  0.9965 ± 0.1593
 2132.7  0.8677 ± 0.1205
 4281.8  0.7413 ± 0.0943

1Ash-Free Dry Weight is reported as the average weight per organism (combination of all replicates within a treatment).

* Significantly less than control (p <= 0.05)

SD =standard deviation

Table 6: Organism reproduction data

 Average measured total Al conc. (µg/L)  Average reproduction (± SD) (number of eggs/case)
 7.5  337.8 ± 125.8
 233.0  340.8 ± 137.0
 490.4  349.3 ± 83.77
 1100.2  288.7 ± 108.7
2132.7   298.2 ± 53.62
 4281.8  269.6 ± 42.48
Validity criteria fulfilled:
yes
Conclusions:
The endpoints analyzed were: 10- day survival and growth, adult emergence, and reproduction. No effect on survival was observed at Day 10 or Day 28. Growth at Day 10 (as ash-free dry weight) was determined to be the most sensitive growth endpoint. The study resulted in a no observable effect concentration [NOEC] of 1100.2 μg/L total Al and a lowest observable effect concentration [LOEC] of 2132.7 μg/L total Al for growth (for Day 10 growth). The effective concentrations to reduce growth by 10% and 20% relative to control performance (EC10 and EC20 with 95% confidence intervals) were 971.6 (220.8 – 4276.0) and 1933.2 (798.3 – 4681.4) μg/L total Al, respectively.
Executive summary:

As part of an environmental program designed to provide data for the setting of water quality standards, data describing the chronic toxicity of aluminum to a variety of aquatic organisms is needed. Aluminum toxicity is a function of the chemical species of aluminum present in the water and this speciation is a function of the physico/chemical properties (e.g., pH) of the water. Efforts are underway to develop data describing the chronic toxicity of aluminum to aquatic organisms at hydrogen ion concentrations (i.e., pH) typical of natural environmental conditions (i.e., pH of 6). The study reported herein describes the chronic toxicity of aluminum, at a pH of 6.0, to the midge, Chironomus riparius. Use of this test organism qualifies as a level of organization (Phylum) to be used as part of the minimum taxonomic requirements for calculation of a predicted no effect concentration (PNEC) for the freshwater aquatic compartment, within the context of a species sensitivity distribution approach (European Commission 2003). C. riparius were exposed to a series of aluminum concentrations for 28 days, starting as 1st instar larvae (3 days old). To allow for potential changes in aluminum speciation, exposure solutions were aged for a 3-hour equilibrium period. As the formation of insoluble chemical species was apparent through low dissolved and monomeric measurements, total Al was used to interpret the biological data in this study. Measured pH values in the test averaged 6.0 – 6.1 in waters immediately prior to organism exposure and averaged 6.5 – 6.7 within the test chambers. Nominal test concentrations ranged from 0 to 5,000 μg Al/L and total, dissolved, and monomeric aluminum were measured throughout the test. As the formation of insoluble chemical species was apparent through low dissolved measurements (all concentrations measuring below 66 μg Al/L), total Al was used to interpret the biological data in this study. The test had measured exposure concentrations ranging from 7.5 to 4281.8 μg total Al/L. A short-term endpoint of survival and growth was measured at day 10. The endpoints analyzed for the entire life-cycle test were adult emergence and reproduction. Additional short-term data of survival and growth was quantified at Day 10. There was no effect on organism short-term survival (at Day 10). The short-term growth endpoint at Day 10 (as ash-free dry weight) was affected at the two highest concentrations. Upon comparison of the full life-cycle chronic endpoints of adult emergence and reproduction (hypothesis testing), there was no statistically significant effect in any of the concentrations, resulting in a no-observable effect concentration (NOEC) and a lowest observable effect concentration (LOEC) of 4281.8 μg/L total Al and > 4281.8 μg/L total Al, respectively. Based upon point estimate analysis of the life-cycle endpoints, reproduction was the most sensitive endpoint, resulting in effective concentrations to reduce reproduction by 10% and 20% relative to control performance (EC10 and EC20 with 95% confidence intervals) of 1271.5 (109.4 – 14776.4) and 3387.0 (858.0 – 13373.0) μg/L total Al, respectively.

Endpoint:
sediment toxicity: long-term
Type of information:
read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
weight of evidence
Justification for type of information:
REPORTING FORMAT FOR THE ANALOGUE APPROACH
[Further information is included as attachment to Iuclid section 13]
Reason / purpose:
read-across source
Reason / purpose:
read-across: supporting information
Duration:
42 d
Dose descriptor:
NOEC
Effect conc.:
453.8 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
mortality
Duration:
28 d
Dose descriptor:
NOEC
Effect conc.:
53.1 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
biomass
Remarks:
growth
Duration:
42 d
Dose descriptor:
NOEC
Effect conc.:
232.6 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
biomass
Remarks:
growth
Duration:
28 d
Dose descriptor:
NOEC
Effect conc.:
123.2 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
growth rate
Remarks:
dry weight
Duration:
42 d
Dose descriptor:
NOEC
Effect conc.:
232.6 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
growth rate
Remarks:
dry weight
Duration:
42 d
Dose descriptor:
NOEC
Effect conc.:
232.6 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
reproduction
Duration:
42 d
Dose descriptor:
LOEC
Effect conc.:
> 453.8 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
mortality
Duration:
28 d
Dose descriptor:
LOEC
Effect conc.:
123.2 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
biomass
Remarks:
growth
Duration:
42 d
Dose descriptor:
LOEC
Effect conc.:
453.8 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
biomass
Remarks:
growth
Duration:
28 d
Dose descriptor:
LOEC
Effect conc.:
232.6 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
growth rate
Remarks:
dry weight
Duration:
42 d
Dose descriptor:
LOEC
Effect conc.:
453.8 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
growth rate
Remarks:
dry weight
Duration:
42 d
Dose descriptor:
LOEC
Effect conc.:
453.8 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
reproduction
Duration:
28 d
Dose descriptor:
EC10
Effect conc.:
142.6 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
biomass
Remarks:
growth
Remarks on result:
other: CL: 66.8-304.2 µg/L
Duration:
42 d
Dose descriptor:
EC10
Effect conc.:
227.7 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
biomass
Remarks:
growth
Remarks on result:
other: CL: 59.2 - 875.9 µg/L
Duration:
28 d
Dose descriptor:
EC10
Effect conc.:
152.3 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
growth rate
Remarks:
dry weight
Remarks on result:
other: CL: 128.3-375.1 µg/L
Duration:
42 d
Dose descriptor:
EC10
Effect conc.:
219.4 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
growth rate
Remarks:
dry weight
Remarks on result:
other: CL: 128.3-375.1 µg/L
Duration:
42 d
Dose descriptor:
EC10
Effect conc.:
170.6 µg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
reproduction
Remarks on result:
other: CL:126.8-229.6
Details on results:
/
Results with reference substance (positive control):
/
Reported statistics and error estimates:
Statistical analysis was performed using measured average total Al concentrations. Differences in survival (at Days 28, 35, and 42), growth (at Days 28 and 42), and reproduction (at Days 35 and 42) were evaluated using a statistical computer package (Comprehensive Environmental Toxicity Information System [CETIS], Tidepool Scientific Software, McKinleyville, CA, USA and Toxicity Relationship Analysis Program [TRAP], Duluth, MN, USA). If the data met the assumptions of normality and homogeneity, the NOEC and LOEC were estimated using an analysis of variance to compare (p = 0.05) organism performance in the experimental treatments with that observed in the control. The median-lethal concentration (LC50) was estimated using linear interpolation. The effective concentrations to reduce survival, growth, or reproduction by 10%, 20%, or 50% relative to control performance (EC10/EC20/EC50) were estimated using threshold sigmoid regression analysis. Exposure concentrations were log-transformed before determination of the EC10, EC20, and EC50 values.

Table 1: Summary of statistics (continued)

 Endpoint  Growth-Biomass    Growth - Dry weight     Reproduction 
   28 -day  42 -day  28 -day  42-day  42 -day
 EC20 (95% CI)  199.3 (116.7 - 340.2)  291.2 (119.9 - 706.8)  207.0 (179.9 -238.2) 277.7 (191.3 -403.0)  197.7 (154.9 -252.3)
EC50 (95% CI)    387.2 (293.0 -511.7)  474.0 (350.2 -641.5)   380.6 (339.0 -427.3)   443.3 (367.9 -534.1) 264.8 (225.6 -310.8) 

Table 2: Summary of Total Metal Analyses (μg/L Al)

 Nominal conc.  Total Al (µg/L)   
   Total average  Total Std Dev
 0  2.2*  -
 28.1 30.9   6.8
 56.3  53.1  11.8
 112.5  123.2  23.9
 225  232.6  28.0
 450  453.8  66.0

* For calculation of average concentrations, the control water has been given a value of 2.2 μg/L Al (half the detection limit).

Table 3: Summary of Dissolved Metal Analyses (μg/L Al)

 Nominal conc.  Dissolved aluminum (µg/L)  
   Dissolved average  Dissolved Std Dev.
 0  2.2*  -
 28.1  3.7  2.1
 56.3  6.5 3.4 
 112.5  11.0  3.0
 225  15.6  5.4
 450  36.0 19.3 

* For calculation of average concentrations, samples below the detection limit are given a value of 2.2 μg/L Al (half the detection limit).

Table 4: Survival

 Average measured Al conc. (µg/L)  Proportion survived (±SD)    
   Day 28  Day 35  Day 42
 2.2  0.92 ± 0.10  0.84 ± 0.11  0.79 ± 0.15
 30.9  0.83 ± 0.07  0.71 ± 0.15  0.69 ± 0.16
 53.1  0.88 ± 0.07  0.86 ± 0.07  0.85 ± 0.08
 123.2  0.79 ± 0.22  0.78 ± 0.27  0.75 ± 0.28
232.6   0.92 ± 0.07  0.80 ± 0.09  0.79 ± 0.11
 453.8 0.92 ± 0.08   0.90 ± 0.11  0.88 ± 0.14

Table 5: Organism growth data (Biomass)

 Average measured total Al conc (µg/L) Average dry weight per original organism in mg ( ±SD)1
   Day 28  Day 42
 2.2  0.419  ± 0.05  0.446  ± 0.09
 30.9 0.379  ±   0.03  0.409  ± 0.07
 53.1  0.367  ± 0.04  0.507  ± 0.05
 123.2  0.321  ± 0.04*  0.486  ± 0.14
 232.6  0.295  ± 0.03*  0.415  ± 0.09
 453.8  0.155  ± 0.02*  0.248  ± 0.04

1 Biomass (average dry weight per original organism) is reported as an average of all replicates within a treatment.

* Significantly less than control (p <= 0.05). SD = Standard Deviation

Table 6: Organism growth data


 Average measured total Al conc. (µg/L)  Dry weight in mg ( ±SD)1 
   Day 28  Day 42
 2.2  0.474  ± 0.09  0.569  ± 0.07
 30.9  0.446  ± 0.03  0.606  ± 0.07
 53.1 0.435  ±   0.06  0.598 ± 0.06
 123.2  0.442  ± 0.04  0.692 ± 0.15
232.6   0.338  ± 0.01*  0.525 ± 0.07
 453.8  0.183  ± 0.03*  0.288 ± 0.06

1 Dry Weight is reported as the average weight per organism (combination of all replicates within a treatment).

* Significantly less than control (p <= 0.05)

Table 7: Organism reproduction data

  Average measured total Al conc. (µg/L) Average reproduction (± SD) (young/female)1
 2.2  9.30 ± 3.69
 30.9  9.36 ± 4.69
 53.1  9.16 ± 4.02
 123.2  7.89 ± 3.95
 232.6  5.85 ± 3.02
 453.8  0.46 ± 0.37*

1 Reproduction is reported as the average number of young per female (sum of Day 35 and 42 divided by # of females; combination of all replicates within a treatment).

* Significantly less than control (p <= 0.05)

Validity criteria fulfilled:
yes
Conclusions:
No effect on survival was observed at 28, 35, or 42-days. Growth (as mean dry biomass) at Day 28 was determined to be most sensitive endpoint. The study resulted in a no observable effect concentration [NOEC] of 53.1 μg/L total Al and a lowest observable effect concentration [LOEC] of 123.2 μg/L total Al for growth (as Day 28 mean dry biomass). The effective concentrations to reduce growth by 10% and 20% relative to control performance (EC10 and EC20 with 95% confidence intervals) were 142.6 (66.8 – 304.2) and 199.3 (116.7 – 340.2) μg/L total Al, respectively.
Executive summary:

As part of an environmental program designed to provide data for the setting of water quality standards, data describing the chronic toxicity of aluminum to a variety of aquatic organisms is needed. Aluminum toxicity is a function of the chemical species of aluminum present in the water and this speciation is a function of the physico/chemical properties (e.g., pH) of the water. Efforts are underway to develop data describing the chronic toxicity of aluminum to aquatic organisms at hydrogen ion concentrations (i.e., pH) typical of natural environmental conditions (i.e., pH of 6). The study reported herein describes the chronic toxicity of aluminum, at a pH of 6.0, to the amphipod, Hyalella azteca. Use of this test organism qualifies as a level of organization (Phylum) to be used as part of the minimum taxonomic requirements for calculation of a predicted no effect concentration (PNEC) for the freshwater aquatic compartment, within the context of a species sensitivity distribution approach (European Commission 2003). H. azteca were exposed to a series of aluminum concentrations for forty-two days, starting as 7-9 day old juveniles. To allow for potential changes in aluminum speciation, exposure solutions were aged for a 3-hour equilibrium period. As the formation of insoluble chemical species was apparent through low dissolved and monomeric measurements, total Al was used to interpret the biological data in this study. Measured pH values in the test averaged 5.7 – 6.3 in waters immediately prior to organism exposure and averaged 6.2 – 6.6 within the test chambers. Nominal test concentrations ranged from 0 to 450 μg Al/L and total, dissolved, and monomeric aluminum were measured throughout the test. The test had measured exposure concentrations ranging from 2.2 to 453.8 μg total Al/L and the endpoints analyzed were: 28-day survival and growth, 35- survival and reproduction, and 42-day survival, growth, and reproduction. Out of the full chronic life-cycle (42 day) endpoints of survival, growth, and reproduction, reproduction was the most sensitive endpoint for the entire life-cycle study, resulting in a no observable effect concentration [NOEC] of 232.6 μg/L total Al and a lowest observable effect concentration [LOEC] of 453.8 μg/L total Al. The effective concentrations to reduce reproduction by 10% and 20% relative to control performance (EC10 and EC20 with 95% confidence intervals) were 170.6 (126.8 –229.6) and 197.7 (154.9 – 252.3) μg/L total Al, respectively.

Endpoint:
sediment toxicity: long-term
Type of information:
experimental study
Adequacy of study:
weight of evidence
Study period:
01/2011-02/2011
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: GLP comparable to guideline study
Reason / purpose:
reference to same study
Reason / purpose:
reference to other study
Qualifier:
according to
Guideline:
other: Bhargava S(1992). General behaviour and mortality of Lymnaea stagnalis and their egg mass undert the stress of thiourea and DDT. J. Fresh Biol., 4, 129-134.
Qualifier:
according to
Guideline:
other: USEPA. 2000. Methods for Measuring the Toxicity and Bioaccumulation of Sediment- associated Contaminants with Freshwater Invertebrates. EPA-600-R-99-064. Office of Research and Development, Duluth, MN.
Qualifier:
according to
Guideline:
other: Slooff W, Canton, J.H. (1983). Comparison of the susceptibility of 11 freshwater species to 8 chemical compounds. II. (semi)chronic toxicity tests. Aquat Toxicol. 4, 277-282.
Principles of method if other than guideline:
/
GLP compliance:
yes
Specific details on test material used for the study:
Details on properties of test surrogate or analogue material (migrated information):
/
Analytical monitoring:
yes
Details on sampling:
- Analytical samples from each treatment were collected

- Sampling method:

TOTAL ALUMINUM:
“New” waters were taken directly from the cubitainer using a 20 mL syringe after the 3-hour equilibrium period. Approximately 5 mL was drawn into the syringe to rinse the inside of the syringe and then expunged. Then 15 mL of sample was drawn into the syringe and injected into a 15 mL polypropylene conical tube. Samples of “old” waters were taken from a composite of each replicate from each concentration. “Old” water was poured off from the top half/layer of the water column within each beaker.

DISSOLVED ALUMINUM/
Approximately 20 mL was drawn into the syringe of which 5 mL was pushed through the filter and discarded; the remaining 15 mL was collected into a 15-mL polypropylene conical test tube for subsequent Al analysis.

MONOMERIC ALUMINUM/
Following collection of a sample for dissolved aluminum analysis, the same filter was used to filter approximately 15 mL aliquots for monomeric aluminum analysis.

- Sample storage conditions before analysis:

TOTAL ALUMINUM-DISSOLVED ALUMINUM: Samples were preserved with trace metal grade nitric acid (AR-ACS grade, Mallinckrodt Chemical, Hazelwood, MO, USA) to pH < 2 and refrigerated (0 - 4 °C) prior to analysis.

MONOMERIC ALUMINUM: Monomeric samples were submitted for immediate analysis.
Vehicle:
no
Details on sediment and application:
PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method:A stock solution of 1000 mg Al/L was prepared by addition of 6.96 grams of Al(NO3)3·9H2O to 500 mL of Milli-Q water in a volumetric flask. The stock solution was then stored in a plastic container in the dark at 0 - 4°C. The pH of the 1000 mg Al/L stock solution was measured at 3.6 - 3.8.
The dilution/ control water used in the toxicity test was reconstituted laboratory water prepared by adding the appropriate reagent grade salts to Milli-Q water to achieve the desired nominal hardness and alkalinity values of 120 and 80 mg/L as CaCO3, respectively. Reconstituted water was prepared as detailed in standard USEPA methods (USEPA 2002).
Test concentrations were prepared by adding the appropriate volume of stock solution (1000 mg/L Al) to the dilution (reconstituted) water. A volumetric flask was filled to approximately 80% of its capacity with the respective dilution (reconstituted) water. Next, the aluminum stock solution was added to the volumetric flask with a micro-pipette to achieve the desired nominal concentration. The volume was then completed to 1500 mL with the respective dilution water. The pH was checked and adjusted to a pH of 6.0 using dilute HCl or NaOH. Each individual concentration was poured into a cubitainer which was then placed (with its cap off) in an “air-tight” enclosure and this enclosure was injected with a pre-determined volume (2.3 – 2.6%) of CO2 to maintain the pH near 6.0. Solutions were held as described for a 3-hour equilibration period in an environmental chamber at test temperature.
- Controls:dilution water control
Test organisms (species):
other: Lymnaea stagnalis
Details on test organisms:
TEST ORGANISM
- Common name: Great Pond Snail
- Justification for species other than prescribed by test guideline: L. stagnalis is a common representative of gastropod molluscs and is an important herbivore/detritivore in many freshwater food webs. Use of this test organism qualifies as a level of organization (Phylum) not otherwise represented as part of the minimum taxonomic requirements for calculation of a predicted no effect concentration (PNEC) for the freshwater aquatic compartment, within the context of a species sensitivity distribution (SSD) approach (European Commission 2003).
- Source: L. stagnalis are cultured at OSU AquaTox. Stock of L. stagnalis egg masses were originally obtained from Dr. Martin Grosell, Rosenstiel School of Marine and Atmospheric Science, University of Miami (Florida, USA).
- Feeding during test: Each test chamber contained one very small piece of lettuce, carrot, and sweet potato.
- Food type: vegetables
- Amount: each vegetable 2-4 mm³ in size
- Frequency: Uneaten food was removed at each water change (Monday, Wednesday, and Friday) and replaced with fresh food to maintain water quality.
Study type:
laboratory study
Test type:
semi-static
Water media type:
freshwater
Limit test:
no
Duration:
30 d
Post exposure observation period:
/
Hardness:
117 mg/L as CaCO3
Test temperature:
25 ± °C
pH:
6.0-6.2
Dissolved oxygen:
> 40%
Salinity:
/
Nominal and measured concentrations:
Nominal concentration: 0, 125, 250, 500,1000, 2000 μg/L
Average measured total Al concentration: <10, 142, 271, 546, 1053, 2063 μg/L
Details on test conditions:
TEST SYSTEM
- Test vessel: 120mL polypropylene Soufflé cups. Because the lid was not air-tight and therefore exchange of CO2 between the chamber and atmosphere would take place, the chambers were placed within an air-tight enclosure injected with CO2 to maintain the pH near 6.0.
- Material, size, headspace, fill volume: fill volume: 120 mL, no headspace
- Renewal rate of test solution (frequency/flow rate):Water changes were performed on a Monday, Wednesday, and Friday schedule with at least 80 - 90% replacement of test solution.
- No. of organisms per vessel: 1
- No. of vessels per concentration (replicates):10
- No. of vessels per control (replicates):10

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: The dilution/ control water used in the toxicity test was reconstituted laboratory water prepared by adding the appropriate reagent grade salts to Milli-Q water to achieve the desired nominal hardness and alkalinity values of 120 and 80 mg/L as CaCO3, respectively. Reconstituted water was prepared as detailed in standard USEPA methods (USEPA 2002). Three batches of reconstituted laboratory water were used for the duration of the study.
- Alkalinity:48mg/L as CaCO3
- Ca/mg ratio:3.02
-DOC: <0.50 mg/L
- Total residual chlorine: <0.05mg/L
- Ammonia: <1.0mg/L
- Calcium: 29.3mg/L
- Magnesium: 9.7mg/L
- Sodium: 34.8mg/L
- Potassium: 7.03mg/L
- Chloride: 51.5 mg/L
- Sulfate: 114mg/L
- Culture medium different from test medium:no
- Intervals of water quality measurement:Certain water quality parameters (i.e., temperature, dissolved oxygen [DO], and pH) were measured in each concentration at test initiation, at renewal, (in both freshly prepared renewal waters and discarded waters), and at test termination. Conductivity was also measured in the freshly-prepared renewal water at test initiation and renewal. Hardness, alkalinity, total residual chlorine, and total ammonia were measured in the dilution water at test initiation and when a newly prepared batch of control/dilution water was used.

OTHER TEST CONDITIONS
- Adjustment of pH: /
- Photoperiod:16:8 hour light:dark cycle
- Light intensity:100 foot candles

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :Observations of live and dead organisms were conducted three times a week (Monday, Wednesday, and Friday). Dead organisms were recorded and immediately removed. At test termination, each surviving organism was blot-dried with a Kimwipe® and weighed to within 0.01 mg.
Reference substance (positive control):
no
Duration:
30 d
Dose descriptor:
NOEC
Effect conc.:
2 099.2 µg/L
Nominal / measured:
meas. (arithm. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
mortality
Duration:
30 d
Dose descriptor:
NOEC
Effect conc.:
1 092 µg/L
Nominal / measured:
meas. (arithm. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
other: wet weight
Duration:
30 d
Dose descriptor:
LOEC
Effect conc.:
> 2 099.2 µg/L
Nominal / measured:
meas. (arithm. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
mortality
Duration:
30 d
Dose descriptor:
LOEC
Effect conc.:
2 099.2 µg/L
Nominal / measured:
meas. (arithm. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
other: wet weight
Duration:
30 d
Dose descriptor:
LC50
Effect conc.:
> 2 099.2 µg/L
Nominal / measured:
meas. (arithm. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
mortality
Duration:
30 d
Dose descriptor:
EC10
Effect conc.:
860.7 µg/L
Nominal / measured:
meas. (arithm. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
other: wet weight
Remarks on result:
other: CL:733.1-1010.5 µg/L
Duration:
30 d
Dose descriptor:
other: EC20
Effect conc.:
1 148.5 µg/L
Nominal / measured:
meas. (arithm. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
other: wet weight
Remarks on result:
other: CL: 1026.7- 1284.7 µg/L
Duration:
30 d
Dose descriptor:
EC50
Effect conc.:
2 036 µg/L
Nominal / measured:
meas. (arithm. mean)
Conc. based on:
element
Remarks:
total Al
Basis for effect:
other: wet weight
Remarks on result:
other: CL: 1944 - 12131.0 µg/l
Details on results:
/
Results with reference substance (positive control):
/
Reported statistics and error estimates:
STATISTICAL ANALYSIS
Statistical analysis was performed using measured average total Al concentrations of newly prepared solutions. Differences in the number of individuals and the intrinsic growth rate and growth at test termination were evaluated using a statistical computer package (Comprehensive Environmental Toxicity Information System [CETIS], Tidepool Scientific Software, McKinleyville, CA, USA and Toxicity Relationship Analysis Program [TRAP], Duluth, MN, USA). If the data met the assumptions of normality and homogeneity, the NOEC and LOEC were estimated using an analysis of variance to compare (p = 0.05) organism performance in the experimental treatments with that observed in the control. The median-lethal concentration (LC50) was estimated using linear interpolation. The effective concentrations to reduce growth by 10%, 20%, or 50% relative to control performance (EC10/EC20/EC50) were estimated using threshold sigmoid regression analysis. Exposure concentrations were log-transformed before determination of the EC10, EC20, and EC50 values.

Table: Summary of biological results

 Average total aluminum (μg/l)  Proportion survived - Average ± Std Dev  Wet weight - Average ± Std. Dev
 5 1.00 ± 0 32.39 ±9.22
175.2   0.90 ± 0.32 31.34 ± 14.67
 309.6  1.00 ± 0 31.68 ± 16.62 
 569.6 0.90 ± 0.32  31.96 ± 10.52
 1092.0 0.67 ± 0.50  26.17 ± 8.94 
 2099.2 1.00 ± 0  15.45 ± 5.78 
Validity criteria fulfilled:
yes
Conclusions:
Total measured exposure concentrations ranged from 5 to 2099 μg Al/L and resulted in no effect on organism survival; however, a significant effect on snail growth was observed at the highest treatment. The study resulted in a no observable effect concentration [NOEC] of 1092 μg/L total Al and a lowest observable effect concentration [LOEC] of 2099 μg/L total Al for growth. The effective concentrations to reduce growth by 10% and 20% relative to control performance (EC10 and EC20 with 95% confidence intervals) was 860.7 (733.1 – 1010.5) and 1148.5 (1026.7 – 1284.7) μg/L total Al, respectively.
Executive summary:

As part of an environmental program designed to provide data for the setting of water quality standards, data describing the chronic toxicity of aluminum to a variety of aquatic organisms are needed. Aluminum toxicity is a function of the chemical species of aluminum present in the water and this speciation is a function of the physico/chemical properties (e.g., pH) of the water. To this end, efforts are underway to develop data describing the chronic toxicity of aluminum to aquatic organisms at hydrogen ion concentrations (i.e., pH) typical of natural environmental conditions (i.e., pH of 6.0).

The study reported herein determines the chronic toxicity of aluminum, at a pH of 6.0, to the great pond snail, Lymnaea stagnalis. Use of this test organism qualifies as a level of organization (Phylum) that is not currently represented as part of the minimum taxonomic requirements for calculation of a predicted no effect concentration (PNEC) for the freshwater aquatic compartment, within the context of a species sensitivity distribution approach (European Commission 2003). In this study, L. stagnalis were exposed to a series of aluminum concentrations for thirty days, starting as newly hatched organisms (<24 hours old). To allow for possible changes in aluminum speciation, exposure solutions were aged for a 3-hour equilibrium period prior to organism exposure. Nominal test concentrations ranged from 0 to 2000 μg Al/L and total, dissolved, and monomeric aluminum were measured throughout the test. As the formation of insoluble chemical species was apparent through low dissolved and monomeric measurements (all concentrations measuring below 100 μg Al/L), total Al was used to interpret the biological data in this study. Total measured exposure concentrations ranged from 5 to 2099 μg Al/L and resulted in no effect on organism survival; however, a significant effect on snail growth was observed at the highest treatment. The study resulted in a no observable effect concentration [NOEC] of 1092 μg/L total Al and a lowest observable effect concentration [LOEC] of 2099 μg/L total Al for growth. The effective concentrations to reduce growth by 10% and 20% relative to control performance (EC10 and EC20 with 95% confidence intervals) was 860.7 (733.1 – 1010.5) and 1148.5 (1026.7 – 1284.7) μg/L total Al, respectively.

Description of key information

Key value for chemical safety assessment

Additional information

Several sediment studies are available on a variety of sediment dwelling species, some of which were directly referenced in the REACH guidance, others which were not but were based on published methodologies and performed in order to collect a large set of chronic data using an array of organisms with different habitats and feeding strategies in order to prepare a Species Sensitivity Distribution for aluminium. Recommended species tested were as follows:  Chirmonus riparius, Hyalella azteca,  Other species:  The snail, Lymnaea stagnalis, the aquatic oligochaete, Aeolosoma sp.  The robust summaries for these species have been compiled together with the results from aquatic toxicity studies, in the section "sediment toxicity" The robust summaries were compiled by the EAA consortium in the Aquatic Toxicity section.  As the aluminium salts consortium acquired these robust summaries directly they have been included directly in the IUCLID  in the sediment toxicity section. They are nonetheless complete.

Aluminium, aluminium powders and aluminium oxide are non hazardous (not classified for the environment). Other aluminium salts transform to practically insoluble forms within days and are no longer bioavailable. Aluminum (Al) is the most commonly occurring metallic element, comprising eight percent of the earth's crust (Press and Siever, 1974) and is therefore found in great abundance in both the terrestrial and sediment environments. Concentrations of 3-8% (30,000-80,000 ppm) are not uncommon.  The relative contributions of anthropogenic aluminium to the existing natural pools of aluminium in soils and sediments is very small and therefore not relevant either in terms of added amounts or in terms of toxicity. Based on these exposure considerations additional sediment and/or soil testing is not warranted. More information about exposure based waiving for aluminium in soil and sediments can be found in attached document (White paper on exposure based waiving for Fe and Al in soils and sediments final 15-03-2010. pdf).