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Bioaccumulation: aquatic / sediment

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Endpoint:
bioaccumulation in aquatic species: fish
Type of information:
experimental study
Adequacy of study:
weight of evidence
Study period:
Not reported
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Non-GLP compliant, non-guideline experimental investigation. Study published in scientific, peer reviewed journal.
Reason / purpose for cross-reference:
reference to same study
Qualifier:
no guideline followed
Principles of method if other than guideline:
Hatchling Cyprinodon variegatus were raised in the presence and absence of sediments contaminated with mixed coal ash over a full life cycle (> 1 yr). The metal concentrations in fish tissues in the end of the experiment were determined.
GLP compliance:
no
Details on sampling:
Fish were stored at -60°C for approx. 6 mo prior to analysis.
Test organisms (species):
Cyprinodon variegatus
Details on test organisms:
Hatchling C. variegatus (1 day posthatching) were derived from laboratory breeding stocks at the Chesapeake Biological Laboratory (16 ppt) and acclimated to the test salinities (5 or 36 ppt) in a stepwise manner over the next 48 h. Following acclimation, 12 hatchlings were selected arbitrarily for weighing of the initial wet mass. Groups of 12 hatchlings from the acclimation tanks were then randomly placed into aquaria of the corresponding salinity. Fish were fed ad lib a mixture of ground flake and pelletized fish food (1:2 flake:pellet) daily throughout the study.
Route of exposure:
sediment
Test type:
semi-static
Water / sediment media type:
natural sediment: marine
Total exposure / uptake duration:
374 d
Salinity:
The experiments were conducated in two levels of salinity: 5 and 36 ppt.
Details on test conditions:
Sediments and water were added to 38-l aquaria arranged randomly in the laboratory. Sediments were added to a depth of 1.5-2 cm in each tank and suspended particles were allowed to settle for a week prior to addition of animals. Tanks were lighted by overhead fluorescent lights on a 12:12 h L:D cycle, and the laboratory was maintained at 23-25°C. Salinity, temperature and dissolved oxygen conditions were monitored in each tank on a weekly basis. Fish were fed ad lib a mixture of ground flake and pelletized fish food (1:2 flake:pellet) daily throughout the study. At approximately 50-75 day intervals, tanks were drained and cleaned, and the sediments and water were replaced. Fish removed from the tanks during cleaning were blotted dry and weighed before being returned to the tanks.
Nominal and measured concentrations:
Concentrations of the trace elements in contaminated sediment (per dry weight) were: Al 4179 ppm, As 43.38 ppm, Ba 484.4 ppm, Cd 0.13 ppm and Cu 30.42 ppm. Concentration of the trace elements in uncontaminated sediments (per dry weight) were: Al 69 ppm, As 1.76 ppm, Ba 0.02 ppm, Cd 0.036 ppm, Cu 3.26 ppm

Details on estimation of bioconcentration:
Bioaccumulation factors were calculated based on the measured tissue and sediment concentrations.
Type:
BAF
Value:
0.006 - 0.9
Basis:
whole body d.w.
Calculation basis:
steady state
Remarks on result:
other: Conc.in environment / dose:69-4179 ppm dw of aluminium
Type:
BAF
Value:
0.081 - 0.835
Basis:
whole body d.w.
Calculation basis:
steady state
Remarks on result:
other: Conc.in environment / dose:1.76- 43.38 ppm dw of arsenic
Type:
BAF
Value:
0.031 - 158.5
Basis:
whole body d.w.
Calculation basis:
steady state
Remarks on result:
other: Higher BAF was from the uncontaminated site
Remarks:
Conc.in environment / dose:0.02-484.4 ppm dw of barium
Type:
BAF
Value:
0.646 - 0.972
Basis:
whole body d.w.
Calculation basis:
steady state
Remarks on result:
other: Conc.in environment / dose:0.036-0.13 ppm dw of cadmium
Type:
BAF
Value:
1.897 - 15.497
Basis:
whole body d.w.
Calculation basis:
steady state
Remarks on result:
other: Higher BAF was from the uncontaminated site
Remarks:
Conc.in environment / dose:3.26-30.42 ppm dw of copper
Reported statistics:
- Growth throughout the duration of the study was significantly higher for control animals than those exposed to contaminants ( F1,68=5.20; P =0.038). However, differences in final wet mass and standard length of each sex between treatments were not significant at the a priori Type I error rate of a =0.05 (P =0.0562-0.104).
- SMR did not differ significantly between contaminant-exposed and control animals (F1,99=1.67; P=0.213).

Concentrations of metal in C. variegatus tissues:

ppm dw  Al As   Ba Cd  Cu
 Contaminated sediment  23.67 ± 5.59 3.51 ± 0.41  15.00 ± 4.27  0.084 ± 0.009  57.70 ± 7.41 
 Uncontaminated sediment  6.18 ± 1.16 1.47 ± 0.33  3.17 ± 0.30  0.035 ± 0.004  50.52 ± 8.03
Validity criteria fulfilled:
not specified
Conclusions:
Concentrations of Al, As, Ba and Cd were 2-4 times higher in fish exposed to contaminated sediment. Concentration of Cu was on the same level in fish from both exposures.
Executive summary:

Bioaccumulation of trace elements in fish Cyprinodon variegatus was studied in non-GLP complient, non-guideline experimental study.

Hatchlings of C. variegatus were raised in the presence and absence of sediments contaminated with mixed coal ash over a full life cycle (> 1 yr) in the laboratory. The metal concentrations in fish tissues in the end of the experiment were determined. Concentrations of Al, As, Ba and Cd were 2-4 times higher in fish exposed to contaminated sediment. Concentration of Cu was on the same level in fish from both exposures. The bioaccumulation factors (BAFs) were mainly < 1. The highest BAFs were obtained for barium and copper for fish in reference conditions.
Endpoint:
bioaccumulation in sediment species, other
Type of information:
experimental study
Adequacy of study:
weight of evidence
Study period:
July 1996-
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Non-GLP compliant, non-guideline experimental investigation. Study published in scientific, peer reviewed journal.
Qualifier:
no guideline followed
Principles of method if other than guideline:
Total body concentrations of 20 trace elements in adult southern toads, Bufo terrestris, inhabiting coal ash settling basins were compared with toads that were not exposed to the combustion wastes (reference). In addition, the accumulation of trace elements in toads transplanted from reference sites to field enclosures in an ash settling basin was studied for 7 and 12 weeks.
GLP compliance:
no
Details on sampling:
Adult male toads, B. terrestris, were concurrently captured at the polluted site and at reference sites. Toads at the polluted site were captured along the road bed between the ash basins and the ash-basin swamp. Toads captured at the polluted site were immediately transported to the laboratory, where they were allowed to void gastrointestinal contents for 7 days. Toads were then sacrificed and frozen for later analysis. Toads captured at reference sites were transported to outdoor enclosures either at the polluted site or at another undisturbed reference site.
Three sediment samples were taken near the enclosures at the ash basin and the reference site. Sediment samples and toads were freeze-dried and homogenized before the analyses.
Test organisms (species):
other: Bufo terrestris
Route of exposure:
sediment
Test type:
field study
Water / sediment media type:
natural sediment: freshwater
Total exposure / uptake duration:
12 wk
Details on test conditions:
Toads captured at reference sites were transported to outdoor enclosures either at the polluted site or at another undisturbed reference site (33°188N, 081°398E) (n=8 enclosure/site). The enclosures were constructed of a PVC (polyvinyl chloride) pipe frame and surrounded by galvanized mesh hardware cloth. Within the enclosures, toads were in direct contact with the sediment and were able to feed on naturally occurring prey items moving freely through the 1.5-cm openings in the hardware cloth. The primary focus of these experiments was to evaluate the endocrine stress response of toads to coal ash effluent. Therefore, toads at both sites were supplementally fed uncontaminated crickets once a week in order to remove food limitation as a potential stressor. Toads remained in the enclosures at the reference site for 12 weeks and at the ash basin for 7 and 12 weeks.They were then transported to the laboratory, held for 7 days to void gut contents, and frozen for later analysis.
Nominal and measured concentrations:
Sediment concentrations at the contaminated site were following (in ppm dry weight):
Ag: 0.048 ± 0.003, Al: 15789.40 ± 234.00, As: 39.638 ±2,809, Ba: 83.80 ± 5.379, Be: 2.467 ± 0.115, Cd: 0.252 ± 0.011, Co: 6.424 ± 0.443, Cr: 10.87 ± 0.815, Cu: 18.39 ± 1.310, Mn: 29.30 ± 2.415, Mo: 3.001 ± 0.181, Ni: 13.73 ± 0.957, Pb: 6.46 ± 0.500, Sb: 0.226 ± 0.025, Se: 4.383 ± 0.188, Sr: 55.82 ± 5.464, Tl: 0.705 ± 0.049, U: 1.001 ± 0.035, V: 28.77 ± 2.275, Zn: 27.10 ± 1.362.
Details on estimation of bioconcentration:
Bioaccumulation factors were estimated based on the monitoring data.
Type:
BAF
Value:
0.02 - 0.04
Basis:
whole body d.w.
Calculation basis:
steady state
Remarks on result:
other: higher value for indigenous toads, lower value for transplanted toads after 12 wk exposure
Remarks:
Conc.in environment / dose:39.638 ppm dry weigh of arsenic
Type:
BAF
Value:
0.85 - 1.6
Basis:
whole body d.w.
Calculation basis:
steady state
Remarks on result:
other: Higher value for indigenous toads, lower value for transplanted toads after 12 wk exposure
Remarks:
Conc.in environment / dose:83.8 ppm dry weight of barium
Type:
BAF
Value:
0.6 - 1.07
Basis:
whole body d.w.
Calculation basis:
steady state
Remarks on result:
other: Higher value for indigenous toads, lower value for transplanted toads after 12 wk exposure
Remarks:
Conc.in environment / dose:0.252 ppm dry weigh of cadmium
Type:
BAF
Value:
1.24 - 1.6
Basis:
whole body d.w.
Calculation basis:
steady state
Remarks on result:
other: Higher value for indigenous toads, lower value for transplanted toads after 12 wk exposure
Remarks:
Conc.in environment / dose:18.39 ppm dry weight of copper
Type:
BAF
Value:
0.11 - 0.23
Basis:
whole body d.w.
Calculation basis:
steady state
Remarks on result:
other: Conc.in environment / dose:6.46 ppm dru weight of lead
Type:
BAF
Value:
0.13 - 0.18
Basis:
whole body d.w.
Calculation basis:
steady state
Remarks on result:
other: Higher value for indigenous toads, lower value for transplanted toads after 12 wk exposure
Remarks:
Conc.in environment / dose:0.226 ppm dry weight of antimony
Type:
BAF
Value:
0.004 - 0.009
Basis:
whole body d.w.
Calculation basis:
steady state
Remarks on result:
other: Higher value for indigenous toads, lower value for transplanted toads after 12 wk exposure
Remarks:
Conc.in environment / dose:15789.4 ppm dry weight of aluminium
Reported statistics:
- Concentrations of all measured elements, with the exception of aluminum and manganese, were significantly (p<0.01) elevated in ash basin sediments in comparison to the reference sediment.
- A number of elements were elevated in toads inhabiting the polluted site, but only concentration of arsenic was significantly elevated statistically (p<0.0001) in comparison to toads from reference sites.

Total body trace element content (ppm dry weight) in adult male toads exposed to reference and contaminated sediments for 12 weeks. * denotes siginificant difference between reference and contaminated site.

  Reference Contaminated
As  0.23 ± 0.05* 0.75 ± 0.04 
Ba  77.20 ± 11.25  71.27 ± 7.34 
Cu  20.80 ± 1.67  22.80 ± 3.66 
Sb  0.02 ± 0.01  0.03 ± 0.00 
Cd   0.12 ± 0.02 0.15 ± 0.03 
Pb   1.06 ± 0.09 1.48 ± 0.30 
Validity criteria fulfilled:
not specified
Conclusions:
Toads (Bufo terrestris) accumulated small amounts of trace elements when exposed to coal ash contaminated sediments.
Executive summary:

Bioaccumulation of trace elements in adult Southers toads, Bufo terrestris, exposed to coal ash contaminated sediment was measured in a non-GLP compliant, non guideline study. Total body concentrations of 20 trace elements in toads inhabiting coal ash settling basins were compared with toads that were not exposed to the combustion wastes (reference). In addition, the accumulation of trace elements in toads transplanted from reference sites to field enclosures in an ash settling basin was studied for 7 and 12 weeks. Bioaccumulation factors were 0.02 - 0.04 for arsenic, 0.85 -1.60 for barium, 0.60 - 1.07 for cadmium, 1.24 - 1.60 for copper, 0.11 - 0.23 for lead, 0.004 - 0.009 for aluminium and 0.13 - 0.18 for antimony. Higher values were obtained for indigenous toads, and lower values for transplanted toads after 12 wk exposure to contaminated sediments. Only tissue concentrations of arsenic in toads exposed to contaminated sediments were significantly higher compared to tissue concentrations of toads exposed to the reference sediment.

Endpoint:
bioaccumulation in aquatic species: fish
Type of information:
experimental study
Adequacy of study:
weight of evidence
Study period:
2004
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Non-GLP compliant, non-guideline experimental investigation. Study published in scientific, peer reviewed journal.
Reason / purpose for cross-reference:
reference to same study
Qualifier:
no guideline followed
Principles of method if other than guideline:
Bryophyte, macroinvertebrate, fish and water samples were collected in areas contaminated by past mining activities in Bravona and Presa rivers, Corsica. The arsenic and antimony concentrations in each sample were analysed.
GLP compliance:
no
Remarks:
A WOE study published in a peer reviewed scientific journal.
Details on sampling:
For each study site, 11 water samples were taken. Conductivity and pH of the samples were measured immendiately. Thereafter the water samples were acidified with HNO3 (1 %).
Bryophyte samples were collected on rocky substrata, rinsed to remove any inorganic particles, taken to laboratory in plastic bags and dried at 60°C for 24 h.
Macroinvertebrate samples were collected using a Surber net and transported to laboratory alive in an isotherm powerbox. In the laboratory, the gut contents of live larvae were purged for 24 h after which the larvae were freeze-dried.
Fish (n=184) were caught by electroshock technique and transported to the laboratory in isotherm powerboxes. Fish were rinsed, measured (weight, length) and dissected. Tissues were freeze-dried. Half of the fish were analysed for their whole body metal content. For another half, different tissues were analysed separately.
Test organisms (species):
other: various species
Details on test organisms:
Bryophyte Fontinalis antipyretica represented a primary producer.
Benthic macroinvertebrates with various functional feeding groups were included in the study:
- Shredders: Leuctra budtzi, Leuctra geniculata, Protonemura bucolica
- Scrapers: Silonella aurata, Baetis cyrneus, Helichus substriatus, Electrogena fallax, Ancylus fluviatilis, Baetis ingridae, Silo rufesens, Esolus brevis, Limnius intermedius
- Collector-gatherers: Caenis martae, Phychomyia pusilla
- Collector-filters: Hydropsyche cyrnotica, Hydropsyche fumata
- Predators: Dugesia benazzii, Rhyacophila pubescens, Isoperla insularis, Rhyacophila tarda
- All the fish used in this study were Salmo trutta.
Route of exposure:
other: aqueous, sediment, feed
Test type:
field study
Water / sediment media type:
natural sediment: freshwater
pH:
pH ranged from 7.19 to 7.95 among the sampling sites
Details on test conditions:
Conductivity of water ranged between 163-296 µS/cm. The concetrations of various ions were following:
Cl-: 6.30-12.6 µg/l
NO2-: 0.01-0.02 g/l
NO3-: 0.60-2.35 µg/l
SO42-: 5.25-23 µg/l
Ca2+: 16.85-28.76 µg/l
Mg2+: 3.69-10.63 µg/l
Fe: 2-11.75 µg/l
Mn: 0-9.75 µg/l
Nominal and measured concentrations:
Concentrations of arsenic in water ranged from 2.13 µg/l (reference) to 2330.83 µg/l and concentrations of antimony from 1.50 µg/l (reference) to 149.25 µg/l. Concetrations of arsenic in sediments ranged from 216.75 µ/g to 9135 µg/g and concentrations of antimony from 31 µg/g to 1056.5 µg/g. The sediment concetrations were from Migon C and Mori C, 1999, Arsenic and antimony release from sediments in Mediterranean estuary, Hydrobiologia 392:81-88.
Details on estimation of bioconcentration:
Bioconcentration factors (BCFs) and bioaccumulation factors (BAFs) were estimated based on monitoring data.
Type:
BCF
Value:
151.73
Basis:
whole body d.w.
Calculation basis:
steady state
Remarks on result:
other: for Fontinalis antpyretica (primary producer)
Remarks:
Conc.in environment / dose:2330.83 µg/l of arsenic
Type:
BCF
Value:
23.55 - 557.19
Basis:
whole body d.w.
Calculation basis:
steady state
Remarks on result:
other: mina and max for 20 macroinvertebrate taxa
Remarks:
Conc.in environment / dose:2330.83 µg/l of arsenic
Type:
BCF
Value:
0.82
Basis:
whole body d.w.
Calculation basis:
steady state
Remarks on result:
other: for Salmo trutta
Remarks:
Conc.in environment / dose:2330.83 µg/l of arsenic
Type:
BCF
Value:
0.62
Basis:
edible fraction
Calculation basis:
steady state
Remarks on result:
other: for Salmo trutta muscle
Remarks:
Conc.in environment / dose:2330.83 µg/l of arsenic
Type:
BCF
Value:
326.4
Basis:
whole body d.w.
Calculation basis:
steady state
Remarks on result:
other: for Fontanalis antpyretica (primary producer)
Remarks:
Conc.in environment / dose:149.08 µg/l of antimony
Type:
BCF
Value:
168.2 - 699.94
Basis:
whole body d.w.
Calculation basis:
steady state
Remarks on result:
other: min and max for 20 macroinvertebrate taxa
Remarks:
Conc.in environment / dose:149.08 µg/l of antimony
Type:
BCF
Value:
3.02
Basis:
whole body d.w.
Calculation basis:
steady state
Remarks on result:
other: for Salmo trutta
Remarks:
Conc.in environment / dose:149.08 µg/l of antimony
Type:
BCF
Value:
1.01
Basis:
edible fraction
Calculation basis:
steady state
Remarks on result:
other: for Salmo trutta muscle
Remarks:
Conc.in environment / dose:149.08 µg/l of antimony
Details on results:
BCFs for macroinvetebrates of various functional feeding groups differed markedly. An average BCF for shredders was 557.19 for arsenic and 699.94 for antimony. For scrapers the BAFs(ave) were 112.2 and 230.25 for arsenic and antimony, respectively. For collector-gatherers, the BAFs(ave) were 90.18 and 230.25 and for collector-filters 69.95 and 332 for arsenic and antimony, respectively. For predators, the BAFs were on an average 23.55 for arsenic and 168.02 for antimony.
Reported statistics:
- Differences among stations were statistically significant for both arsenic (F6,51 = 56.69, p < 0.0001) and antimony (F6,51 = 23.22, p < 0.0001). Tukey’s HSD post-hoc procedure indicated that metalloid contents fromP2 and P3 station sites were significantly different from those of the other station sites.
- Concentrations of arsenic and antimony are tightly correlated along the axial course of the Presa and the Bravona systems (Pearson r = 0.87, p < 0.0001). Bryophytes burden statistically differ among stations (As: F3,45 = 115.47, p < 0.0001, r2 = 0.88; Sb: F3,45 = 92.42, p < 0.0001, r2 = 0.86). Tukey’s HSD post-hoc procedure indicated that metalloids burdens from P2 were significantly different from those of B1, P1, and B3.
- A significant correlation was found between the levels of arsenic and antimony in bryophytes and the levels of metalloids in water samples (respective Pearson correlations: 0.94 and 0.96, p < 0.0001).
- In PCA the first two axes explain 92.5% of the total variance. Component 1 (PC1) explains 68.0% of the total variance, burden of arsenic (40%), and burden of antimony (39%) having the most important contributions. Increasingly positive PC1 scores along this axis indicate increasing arsenic and antimony burdens in invertebrates (respective correlations: 0.91 and 0.89), and decreasing rheophily of the species (correlation: −0.65). Component 2 (PC2) explains 24.4% of the total variance, flow preference (limnophilic/rheophilic) of the species having the most important contribution (79.2%). Increasingly positive PC2 scores along this axis indicate increasingly rheophilic species (correlation: 0.76).

Bioaccumulation factors (BAFs), defined as ratios of metalloids in between the consumers and diets were following:

 Trophic link  BAF/As BAF/Sb 
 Bryophyte --> gatherer scrapers 0.713 1.182 
 Scrapers-shredders- collectors --> predators 0.126  0.384 
 Total invertebrates --> trout (whole body) 0.005  0.008 
 Total invertebrates --> trout (muscle) 0.004  0.003 
     
Conclusions:
Arsenic and antimony accumulated in benthic macroinvertebrates but the accumulated concentrations were depended on the functional feeding group. Fish (Salmo trutta) accumulated only small concentrations of arsenic and antimony, and only a fractions of the metalloids were present in the edible part (muscle).
Executive summary:

Bioaccumulation of arsenic and antimony in organisms of different trophic levels was studied in non-GLP compliant, non-guideline experimental study. Bryophyte, macroinvertebrate, fish and water samples were collected in areas contaminated by past mining activities in Bravona and Presa rivers, Corsica. The arsenic and antimony concentrations in each sample were analysed. Bioconcentration factors (BCFs) decreased along increasing trophic status. Bioconcentration factors of shedders feeding on decomposing vascular plant tissue or coarse particulate organic matter were highest among the macroinvertebrates (557.19 for As and 699.94 for antimony), whereas the BCFs for predators were lowest (23.55 for arsenic and 168.02 for antimony). For fish the whole-body BCFs were 0.82 for arsenic and 3.02 for antimony.

Endpoint:
bioaccumulation in aquatic species, other
Type of information:
experimental study
Adequacy of study:
weight of evidence
Study period:
no data
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Non-GLP compliant, non-guideline experimental investigation. Study published in scientific, peer reviewed journal.
Principles of method if other than guideline:
Environmental behaviour, cell-associated surface absorption/adsorption and toxicity of aluminium at neutral pH to the alga Chamydomonas gigantea in the presence and absence of the key Al-binding ligand silica. Also, transfer of Al from C. gigantea to planktonic crustacea Daphnia pulex was studied. Finally, the effect of Al on elemental composition (and hence nutritional value) was studied.
GLP compliance:
no
Remarks:
A WOE study published in a peer reviewed scientific journal.
Test organisms (species):
other: Chlamydomonas gigantea, Daphnia pulex
Details on test organisms:
Stock cultures of the green alga C. gigantea (obtained from Sciento Ltd., Manchester) were grown in sterilized Jaworsky Medium prepared with deionised water. Cultures were maintained in a growth chamber under constant light–temperature regime (50 μmol photons m−1 s−1; 19 °C; 16–8 h light–dark cycle). All cultures and experimental solutions were prepared in acid-washed polycarbonate or polypropylene plastic ware to avoid contamination with Al and Si. Stock cultures of D. pulex were initiated with organisms isolated from Rostherne Mere, a well-studied unpolluted lowland lake in North Cheshire. Populations were cultured in lake water previously filtered (0.45 μm) and sterilized by autoclaving at 15 psi for 15 min. Cultures were maintained under continuous aeration and with a similar temperature and light regime to that described above. The Daphnia were fed C. gigantea at a concentration of 19.9×10^3+1.0×10^3 cells ml−1 at intervals of two to three days.
Route of exposure:
aqueous
Test type:
static
Total exposure / uptake duration:
ca. 16 d
Details on test conditions:
Thirty conical polycarbonate flasks containing 200 ml of JM without EDTA were inoculated with 5 ml of C. gigantea stock culture containing 1×10^5 cells ml−1 grown. Three replicates were run in parallel for each treatment and the control, making a total of 15 flasks. A further 15 flasks containing no C. gigantea allowed the behaviour of Al and Si in the culture medium in the presence of algae to be corrected for physical–chemical processes such as absorption into the walls of the flasks. The pH was adjusted to 7.0±1.0 and the cultures were incubated for 16 days under the environmental conditions. To study transfer of Al in food chain Daphnia were fed C. gigantea exposed to 500 μgl−1 Al.
At the end of the exposure period of 16 days, both the concentration of Al associated with the cells (‘biosorbed’; this is adsorbed and accumulated) and the concentration of Al incorporated into the cells (‘accumulated’) were analysed following exposure to 50 and 500 μgl−1 added Al only. The cells were pelleted, dried and acid digested as above. Analysis of the amount of Al incorporated into the cells was carried out in a further set of samples. Pelleted cells were suspended in 0.1 M EDTA for 20 min in order to remove Al adsorbed onto the cell surface, then processed and analysed by ICP-AES . Approximately 60 Daphnia from each treatment plus control (no added Al) were homogenized and prepared for analysis of Na, Mg, P, S, Cl, K, Ca, Fe and Si using EDXRMA as freeze-dried microdroplets. These droplets were prepared by placing a 100 μl of homogenate on an EM stub after freeze-drying as previously described.
Remarks on result:
not measured/tested
Remarks:
No bioaccumulation factors were determined in the study. The biosorption (here defined as encompassing both adsorption onto the surface and absorption into the cell) and toxicity of aluminium at neutral pH to Chlamydomonas gigantea was studied in a non-GLP compliant experiment.
Details on results:
The amount of Al biosorbed by C. gigantea in the presence and absence of added Si after 16 days exposure significantly increased (p<0.001) compared to controls only following exposure to 500 μgl−1 Al, from 0.1 mg Al g−1 in the control to 5.9 mg Al g−1 in 500 μgl−1 Al treatment. Addition of Si had no effect (p>0.001) on the amount of Al biosorbed by the cells at either exposure concentration.

Amounts of accumulated Al in C. gigantea (EDTA-washed cells) exposed to 50 and 500 μgl−1 Al without Si increased (p<0.01) from 0.13 to 1.9 mg g−1. Comparison with the amount of Al biosorbed by C. gigantea indicates that 39% and 33% of Al was incorporated into the cell. In the presence of Si, 0.1 and 1.1 mg g−1 Al was accumulated in 50 and 500 μgl−1 Al treatments, respectively—aqueous Si therefore decreased (by 14%; p<0.05) the amount of Al accumulated by C. gigantea exposed to 500 μgl−1 Al whereas it had no effect (p>0.05) at 50 μgl−1 Al.

Biosorption and accumulation of Al by C. gigantea showed variable behaviours in relation to concentration of added Al and time of exposure.Biosorption of Al by C. gigantea was not observed in between 4 and 16 days at low (50 µg/L and medium (100 µg/L) concentrations but only at the highest added concentration (500 µg/L).

Addition of Na2SiO3(5 mg l−1) had no effect on biosorption of 500 μg l−1Al (biosorption was not observed at 50 and 100 μg l−1Al) after 4 h and 16 days exposure but significantly reduced biosorption at 24 h.Silica did however decrease the amount of Al accumulated by C. gigantea after 16 days.

Validity criteria fulfilled:
not specified
Conclusions:
Silica reduced biosorption, accumulation and toxicity of Al by C. gigantea.
Executive summary:

The biosorption (here defined as encompassing both adsorption onto the surface and absorption into the cell) and toxicity of aluminium at neutral pH to Chlamydomonas gigantea was studied in a non-GLP compliant experiment. The biosorption of aluminium from the water column by C. gigantea in the presence and absence of silicic acid was examined over long term (16 days). Biosorption and accumulation of aluminium by C. gigantea showed variable behaviours in relation to concentration of added aluminium and time of exposure. Biosorption of aluminium by C. gigantea was not observed in between 4 and 16 days at low (50 µg/L and medium (100 µg/L) concentrations but only at the highest added concentration (500 µg/L).

Addition of Na2SiO3 (5 mg l−1) had no effect on biosorption of 500 μg l−1 aluminium (biosorption was not observed at 50 and 100 μg l−1 aluminium) after 4 h and 16 days exposure but significantly reduced biosorption at 24 h. Silica did however decrease the amount of aluminium accumulated by C. gigantea after 16 days. The reduced biosorption and accumulation may be due to a decrease in binding aluminium o the cell following the formation of HAS (hydroxyaluminosilicates).

Binding of aluminium by Si can ameliorate the toxicity of the metal due to the formation of biologically unavailable compounds such as HAS.

Endpoint:
bioaccumulation in aquatic species, other
Type of information:
experimental study
Adequacy of study:
weight of evidence
Study period:
Not reported
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Non-GLP compliant, non-guideline experimental investigation. Study published in scientific, peer reviewed journal.
Reason / purpose for cross-reference:
reference to same study
Qualifier:
no guideline followed
Principles of method if other than guideline:
Crayfish were collected from contaminated and non-contaminated areas. Four individuals from each site was used for determination of whole-body concentrations of coal-ash-related trace elements. A total of 23 and 19 individuals from the contaminated and uncontaminated sites, respectively, were used for measurement of standard metabolic rate and growth.
GLP compliance:
no
Details on sampling:
Adult grayfish were collected from the study sites using minnow traps and taken to the laboratory.
Test organisms (species):
other aquatic crustacea: Procambarus acutus
Details on test organisms:
Crayfish were collected from contaminated and uncontaminated areas. Individuals that appeared unhealthy were removed and excluded from the study.
Route of exposure:
other: aqueous/sediment
Test type:
field study
Water / sediment media type:
natural sediment: freshwater
Nominal and measured concentrations:
Concentrations of trace elemets were following:
Sediment from the contaminated area (per dry weight): As 39.64 ppm, Cd 0.25 ppm, Cr 10.87 ppm, Cu 18. 39 ppm, Pb 6.46 ppm and Se 4.38 ppm
Water from the contaminated area: As 17.17 ppm, Cd 0.11 ppm, Cr 0.44 ppm, Cu 2.53 ppm, Pb 0.08 ppm, Se 7 ppm
Sediment from the uncontaminated area: As 0.34 ppm, Cd 0.03 ppm, Cr 7.02 ppm, Cu 4.04 ppm, Pb 4.22 ppm, Se 0.1 ppm
Water from the uncontaminated area: As 0.35 ppm, Cd 0.04 ppm, Cr 0.07 ppm, Cu 1.04 ppm, Pb 0.03 ppm



Details on estimation of bioconcentration:
Bioconcentration factors (BCFs) and bioaccumulation factors (BAFs) were estimated based on monitoring data.
Type:
BCF
Value:
0.23 - 2.71
Basis:
whole body d.w.
Calculation basis:
steady state
Remarks on result:
other: Conc.in environment / dose:0.35-17.17 ppm As
Type:
BAF
Value:
0.1 - 2.79
Basis:
whole body d.w.
Calculation basis:
steady state
Remarks on result:
other: Conc.in environment / dose:0.34-39.64 ppm (dw) of As
Type:
BCF
Value:
7.25 - 44.36
Basis:
whole body d.w.
Calculation basis:
steady state
Remarks on result:
other: Conc.in environment / dose:0.04-0.11 ppm of Cd
Type:
BAF
Value:
9.67 - 19.52
Basis:
whole body d.w.
Calculation basis:
steady state
Remarks on result:
other: Conc.in environment / dose:0.03-0.25 ppm (dw) of Cd
Type:
BCF
Value:
3.11 - 9.42
Basis:
whole body d.w.
Calculation basis:
steady state
Remarks on result:
other: Conc.in environment / dose:0.07-0.44 ppm of Cr
Type:
BAF
Value:
0.09 - 0.13
Basis:
whole body d.w.
Calculation basis:
steady state
Remarks on result:
other: Conc.in environment / dose:7.02-10.87 ppm (dw) of Cr
Type:
BCF
Value:
45.18 - 90
Basis:
whole body d.w.
Calculation basis:
steady state
Remarks on result:
other: Conc.in environment / dose:1.04-2.53 ppm of Cu
Type:
BAF
Value:
11.63 - 12.68
Basis:
whole body d.w.
Calculation basis:
steady state
Remarks on result:
other: Conc.in environment / dose:4.04-18.39 ppm (dw) of Cu
Type:
BCF
Value:
2.1
Basis:
whole body d.w.
Calculation basis:
steady state
Remarks on result:
other: Conc.in environment / dose:7 ppm of Se
Type:
BAF
Value:
3.36 - 24.1
Basis:
whole body d.w.
Calculation basis:
steady state
Remarks on result:
other: Conc.in environment / dose:0.1-4.38 ppm (dw) of Se
Reported statistics:
- During the first interval of the study (days 0-27, contaminant-exposed individuals experienced significantly lower instantaneous growth rates and relative change in mass (P=0.007). During the remaining portion of the experiment (days 28- 50), average instantaneous growth rates remained
lower for contaminant-exposed individuals (P = 0.046). During this interval, relative change in mass also remained lower for contaminant-exposed individuals compared to individuals in the reference treatment (P=0.039).
- There was no difference in mortality between treatments at either sampling time (day 27 or 50). By day 27, four of 12 crayfish in the contaminated
treatment and one of 12 crayfish in the reference treatment died (X2=2.27, P=0.132). By day 50, five and four crayfish of the original 12 had died in the contaminated and reference treatments, respectively (X2=0.178, P=0.673).
Conclusions:
Whole-body trace elements (As, Cd, Cr, Cu, Se) were 2-16-fold higher in crayfish collected from the contaminated site than in the reference sites.
Executive summary:

Bioaccumulation of ash-derived trace elements in crayfish (Procambarus acutus) was studied in a non-GLP compliant, non-guideline experimental study. Crayfish were collected from contaminated and non-contaminated areas. A part of individuals from each site was used for determination of whole-body concentrations of coal-ash-related trace elements. Another part of individuals from the contaminated and uncontaminated sites were used for measurement of standard metabolic rate and growth. Whole-body trace elements (As, Cd, Cu) were 2-16-fold higher in crayfish collected from the contaminated site than in the reference sites. Accumulation ranked as Cd > Cu > As. Standard metabolic rates (SMR) i.e. hourly rates of oxygen consumption by post-absorptive individuals at rest were approx. 30 % higher in the individuals exposed to contaminated sediment, which was associated with reduction of growth rates. However, the differences in SMRs of individuals exposed to contaminated and uncontaminated sediments disappeared between 27 and 50 days of exposure.

Endpoint:
bioaccumulation in sediment species, other
Type of information:
experimental study
Adequacy of study:
weight of evidence
Study period:
May 2004-
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Non-GLP compliant, non-guideline experimental investigation. Study published in scientific, peer reviewed journal.
Qualifier:
no guideline followed
Principles of method if other than guideline:
Clams were transplanted from a reference stream to a stream receiving coal-fired power plant discharge. Trace element accumulation was assessed at five stations along a contamination gradient. Also, resident clams from the most contaminated site were collected for the trace element analysis.
GLP compliance:
no
Remarks:
A WOE study published in a peer reviewed scientific journal.
Details on sampling:
On the day before the transplant experiment began, approximately 400 clams were collected from the reference site and transplanted in the study sites. Site A was immediately downstream (< 5 m) of the outfall from the lentic habitat; Site B was approximately 400 m downstream from the outfall; Site C was 1400 m downstream from the outfall; and Site D was approximately 3.2km downstream from the outfall. The fifth site was a reference stream, Meyers Branch, a historically unimpacted black waterstream. Clam collection dates occurred 28, 56, and 84 days after transplantation. On each date, two clams were randomly selected from each of the four cages for trace element analysis. On each sampling date, water and sediment from all sites were collected. Water samples were filtered in the field and acidified with nitric acid prior to freezing. Field blanks using deionized–distilled water were treated in the same manner. Three replicate grab samples of sediment from each site were frozen at -70°C, and freeze dried. Clams being analyzed for trace elements were held in aerated site water for 24 h before freezing at -70°C. Resident clams from each site were also collected for analyses.
Test organisms (species):
other: Corbicula fluminea
Details on test organisms:
Clams were collected from the field (reference site). Their average length was 17.49 ± 0.37mm.
Route of exposure:
sediment
Test type:
field study
Water / sediment media type:
natural sediment: freshwater
Total exposure / uptake duration:
84 d
Hardness:
Hardness ranged from 20.50 ± 0.94 (Site C) to 38.00 ± 1.38 (Site A) mg CaCO3/l.
Test temperature:
Temparature ranged from 22.48 ± 0.61°C (reference) to 30.94°C (Site A).
pH:
pH ranged from 7.25 ± 0.16 (Site B) to 7.43 ± 0.22 (Site A).
Dissolved oxygen:
Dissolved oxygen concentration ranged from 7.00 ± 0.38 mg/l (Site D) to 7.48 ± 0.36 mg/l (reference)
Details on test conditions:
Twenty clams from the reference site were added to each of four cages (four plastic boxes (31x18x11 cm3) with holes drilled along the sides were secured with aluminum poles). Sediment surrounding the cages at each site was used to fill the plastic boxes and provide a habitat for the clams. After adding sediment from the site and clams from the reference site, cages were covered on the top with netting to prevent loss of clams and sediment. Cage locations were chosen to minimize differences in sediment particle size, depth, and flow conditions among the five study sites.
Nominal and measured concentrations:
Concentration of trace elements in sediments were following (expressed as µg/g dw ):
Reference: Ni: 3.98±2.96, Cu: 4.36 ± 3.17, Zn: 58.20 ± 12.50, As: 1.33 ±0.93, Cd: 0.02 ± 0.02
Site A: Ni: 2.46 ± 0.48, Cu: 3.70 ± 0.56, Zn: 17.62 ± 1.26, As: 1.41± 0.27, Cd: 0.08 ± 0.04
Site B: Ni: 10.39 ± 3.11, Cu: 14.12 ± 5.08, Zn: 39.09 ± 5.74. As: 4.44 ± 1.38, Cd: 0.09 ± 0.03
Site C: Ni: 3.59 ± 0.64, Cu: 5.01 ± 1.29, Zn: 52.82 ± 8.60, As: 1.21 ± 0.65, Cd: 0.11 ± 0.09
Site D: Ni: 2.02 ± 0.16, Cu: 2.33 ± 0.33, Zn: 33.56 ± 15.50, As: 0.56 ± 0.05, Cd: 0.02 ± 0.00
Details on estimation of bioconcentration:
Bioaccumulation factors were calculated based on measured data.
Type:
BAF
Value:
14.6
Basis:
whole body d.w.
Time of plateau:
60 d
Calculation basis:
steady state
Remarks on result:
other: Conc.in environment / dose:3.70 µg/g dw of copper
Type:
BCF
Value:
21.4
Basis:
whole body d.w.
Time of plateau:
60 d
Calculation basis:
steady state
Remarks on result:
other: Conc.in environment / dose:2.53 µg/l of copper
Type:
BAF
Value:
0.45
Basis:
whole body d.w.
Time of plateau:
20 d
Calculation basis:
steady state
Remarks on result:
other: Conc.in environment / dose:1.41 µg/g dw of arsenic
Type:
BCF
Value:
0.43
Basis:
whole body d.w.
Time of plateau:
20 d
Calculation basis:
steady state
Remarks on result:
other: Conc.in environment / dose:18.31 µg/l of arsenic
Type:
BAF
Value:
91
Basis:
whole body d.w.
Time of plateau:
80 d
Calculation basis:
steady state
Remarks on result:
other: Conc.in environment / dose:0.08 µg/g dw of cadmium
Type:
BCF
Value:
56
Basis:
whole body d.w.
Time of plateau:
80 d
Calculation basis:
steady state
Remarks on result:
other: Conc.in environment / dose:0.13 µg/l of cadmium
Details on results:
Clams were found the accumulate Cu, Cd and As. Concentrations of Cu and Cd in clam tissues peaked in the beginning of the test (28 d), and decreased thereafter. Concentration of As stayed on the same level throughout the test. Tissue concentrations of the transplanted clams correlated with dissolved concentrations (r > 0.60, p < 0.005). Trace element concentrations were higher in the resident clams compared to transplanted clams.
Clam mortality was less than 1 % during the study. Clams from Site A had the highest growth rate and condition index.
Reported statistics:
- Concentrations of Ni, As, Se, and Cd in the tissue of transplanted clams were significantly greater (p < 0.05) at Site A compared to all other sites throughout the study. Hg concentrations in the tissues of transplanted clams at Site A decreased during the experiment and, by the end of the study, were significantly lower (p<0.01) than at all other sites.
- Ni, Cu, As, Se, and Cd tissue concentrations in transplanted clams were highly correlated with dissolved concentrations (r>0.60, p<0.005). However, these correlations were driven by elevated tissue and dissolved concentrations in clams at SiteA; when this site was removed from the analysis,none of the correlations were significant.
- Trace element concentrations in resident clams at Site A were significantly different than transplanted clams throughout the study (p < 0.01). Ni, Cu, Zn, As, Se, and Cd concentrations were significantly (p < 0.01) higher in resident clams at the completion of the study. In contrast, despite significant declines, Hg concentrations in transplanted clams at Site A were significantly (p < 0.01) higher than resident clams at the same site throughout the study.
- Clam growth rate was significantly (p<0.05) higher at Site B than at the reference site, but significantly (p<0.05) lesser than at Site A. However, water temperatures varied significantly among sites (p<0.0001) and log[growth rate] increased with mean temperature across all sites (r2=0.68, p<0.0001).

Table 1 Mean trace element concentrations (µg/g dry weight) in Corbicula fluminea from Savannah River Site (day 84, resident and transplant, N=8). Significant differences (p < 0.05) from ANOVA tests are denoted by letters.

 Cu  As  Cd
 SRS-Resident  123.66a± 24.31  9.45a± 0.19  12.64a± 0.65
 SRS-Transplant  54.13bc± 2.45  7.85b± 0.25  7.28b± 0.34
Validity criteria fulfilled:
not specified
Conclusions:
Trace elements associated with coal combustion wastes are bioavailable to benthic organisms in a stream receiving discharge from coal-ash settling basins.
Executive summary:

Bioaccumulation of trace elements (Cu, As, and Cd) in clam Corbicula fluminea was determined in a non-GLP complient, non-guideline experimental study. Clams were transplanted from a reference stream to a stream receiving coal-fired power plant discharge. Trace element accumulation was assessed at five stations along a contamination gradient. Also, resident clams from the most polluted site (Site A) were collected for trace element analysis.

Clams were found the accumulate Cu, Cd and As. Concentrations of Cu and Cd in clam tissues peaked in the beginning of the test (28 d), and decreased thereafter. Concentration of As stayed on the same level throughout the test. Tissue concentrations of the transplanted clams correlated with dissolved concentrations (r > 0.60, p < 0.005). Trace element concentrations were higher in the resident clams compared to transplanted clams. Tissue concentrations of the transplanted clams correlated with the concentrations of dissolved metals. Bioconcentration factors were 0.5, 48.9, and 97.2 for As, Cu and Cd, respectively.

Description of key information

Bioaccumulation of the critical components of ash (As, Sb, Ba, Cd, Cu and Pb) was estimated based on five scientific publications. Three of them were field studies in which bioaccumulation of trace elements in coal fly ash contaminated environment was measured in clams, crayfish and toad. The fourth publication described a laboratory experiment in which fish was exposed to coal fly ash contaminated sediment over a full life cycle. The fifth publication was based on a field experiment in which bioaccumulation of As and Sb in various organisms of different trophic levels was studied in environment contaminated by former mining industry. Studies show that whole-body concentrations of trace elements were 2-16-fold higher in crayfish, fish and clams exposed to the contaminated sediments. Bioaccumulation of As and Sb was found depended on the organisms and decreased along increasing trophic status. 
The critical components were selected based on the following criteria; 1) They were found to be bioavailable in acetate leaching test (> 20 % of the total concentration was extractable in acetate), 2) Their concentrations in ash exceeded the guidance limits set by Finnish authorities for contaminated soils, 3) Their bioavailable concentrations in ash exceeded the TDI (Total Daily Intake).

Key value for chemical safety assessment

BCF (aquatic species):
107

Additional information

The macroelements in Ash (Ca, Fe, Mg, P, K, Na and Si) except for aluminium, are essential to all living organisms (flora and fauna) and their intracellular and extra-cellular concentrations are actively regulated. Therefore, bioaccumulation is not expected. Dissolved aluminium (Al) is generally at low concentrations in neutral freshwater due to its insolubility. Silica, which is an important component in the Ash, has also been found to reduce biosorption, accumulation and toxicity of Al (Quiroz-Vázqueza et al, 2010).

The critical components of Ash (As, Ba, Cd, Cu, Sb) are not essential elements and have been found to bioaccumulate in organisms living in the contaminated environment. The degree of bioaccumulation, however, depends on metal, organism and the environmental conditions. In crayfish and clams, whole-body trace elements were 2-16-fold higher collected from the contaminated site than at the reference sites (Loeffler Peltier et al 2009, Rowe et al 2001). Accumulation in crayfish ranked as Cd > Cu > As. Lead was not found to bioaccumulate. In clam, accumulation ranked as Cu > Cd > As. In fish, accumulation ranked as Cu > Cd > As > Ba > Al (Rowe 2003). Toads were found to accumulate very low amounts of trace elements and only the tissue concentration of arsenic in toads exposed to coal ash contaminated sediment was significantly higher compared to reference toads (Hopkins et al 1998) . Bioaccumulation in toads ranked as Cu > Ba > Cd > Sb > Pb > As > Al. Bioaccumulation of As and Sb in macroinvertebrates was found to be highest in shedders feeding on decomposing vascular plant tissue or coarse particulate organic matter and lowest for predators (Culioli et al 2009). Bioaccumulation of As and Sb in fish was low. Also, ash application in the drainage basins of two small lakes did not increase cadmium concentrations in perch or water slater (Tulonen et al. 2003).

BCF (aquatic species) was calculated as an average of BCFs reported for all trace elements and all organisms.