The product from the burning of a combination of carbonaceous materials.

Sediment toxicity

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

sediment toxicity: long-term

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:

Standard metabolic rates (SMR) of crayfish inhabiting the site contaminated with coal ash were compared with SMR of crayfish from uncontaminated reference sites. SMR of individuals collected from the reference areas and exposed in the laboratory for 50 days to sediment and food derived from the contaminated site were also examined.

GLP compliance:

no

Details on sampling:

Adult crayfish were collected from the study sites using minnow traps and taken to the laboratory. Crayfish were removed daily
from traps, taken to the laboratory, and acclimated for 5 days in dechlorinated tap water. During the acclimation period, crayfish were unfed, and the temperature of the holding room was maintained at 25°C. Individuals that appeared unhealthy (e.g. displayed trapping-related damage or were unresponsive to prodding) were removed and excluded from the study. A total of 23 and 19 individuals from the contaminated and uncontaminated sites,respectively, were subsequently used for measurement of standard metabolic rate. Four additional crayfish from each site were used for determination of whole-body concentrations of coal ash-related trace elements by inductively coupled plasma-mass spectrometry. Sediment and food were also collected from both contaminated and reference sites.

Test organisms (species):

other: Procambbarus acutus

Details on test organisms:

Crayfish were collected from contaminated and uncontaminated areas. Individuals that appeared unhealthy were removed and excluded from the study. Adult crayfish were collected from D-Area swamp and reference sites during June and July using minnow traps. Crayfish were removed daily from traps, taken to the laboratory, and acclimated for 5 days in dechlorinated tap water. Animals from reference sites were pooled as a single reference group. During the acclimation period, crayfish were unfed, and the temperature of the holding room was maintained at 25°C. A total of 23 and 19 individuals from the contaminated and uncontaminated sites, respectively, were subsequently used for measurement of standard metabolic rate.

Study type:

semi-field study

Test type:

not specified

Water media type:

freshwater

Type of sediment:

natural sediment

Duration:

50 d

Exposure phase:

total exposure duration

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 test conditions:

A laboratory experiment in which adult crayfish from uncontaminated reference sites were exposed to sediments and food collected from D-Area Swamp or an uncontaminated reference site was conducted. Crayfish were held individually in 24 20-L aquaria containing 3 cm of contaminated or uncontaminated sediments from the respective study sites (12 aquaria per site) and filled with dechlorinated tap water. Visible pieces of detritus were removed from sediments prior to the study. Feeding was ad lib by daily addition of food (largemouth bass filet portions) previously collected from the contaminated or uncontaminated study sites. At 24-h intervals, uneaten food was removed and replaced with fresh food. The laboratory remained at 23-24°C during the study. After 27 and 50 days, standard metabolic rate (SMR) was measured for all individuals following a period of 5 days, during which they were unfed.

Duration:

50 d

Remarks on result:

not measured/tested

Remarks:

The endpoints of the study included standard metabolic rate (SRM), growth rate, relative changes in mass, and mortality. No LC-, EC-, NOEC or LOEC values were determined.

Details on results:

Mean SMR was significantly higher for crayfish collected from the contaminated site than for those collected in the uncontaminated reference site. Exposure to contaminated sediments and food for 27 days in the laboratory also led to an increase in SMR, but the difference between treatments was not retained through the remainder of the experiment. Instantaneous growth rates and relative changes in mass in the laboratory reflected trace element exposure. During the first interval of the study (days 0-27), contaminant-exposed individuals experienced significantly lower instantaneous growth rates and relative change in mass (9 vs. 21% change for contaminated and reference, respectively). During the remaining portion of the experiment (days 28-50), average instantaneous growth rates remained lower for contaminant-exposed individuals. During this interval, relative change in mass also remained lower for contaminant- exposed individuals compared to individuals in the reference treatment (11 vs. 27 %), respectively. There was no difference in mortality between treatments at either sampling time (day 27 or 50) in the contaminated and reference treatments, respectively. By day 27, four of 12 crayfish in the contaminated treatment and one of 12 crayfish in the reference treatment died. By day 50, five and four crayfish of the original 12 had died in the contaminated and reference treatments, respectively.

Reported statistics and error estimates:

- During the first interval of the study (days 0-27), contaminant-exposed individuals experienced significantly lower instantaneous growth
rates (P = 0.007) and relative change in mass (9 vs. 21% change for contaminated and reference, respectively; 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 (11 vs. 27%, respectively; 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(X2 =0.178, P = 0.673).

The endpoints of the study included standard metabolic rate (SRM), growth rate, relative changes in mass, and mortality.

No LC-, EC-, NOEC or LOEC values were determined.

Validity criteria fulfilled:

not specified

Conclusions:

Mean SMR was significantly higher for crayfish collected from the contaminated site than for those collected in the uncontaminated reference
site. Exposure to contaminated sediments and food in the laboratory also led to an increase in SMR but the difference between treatments was not retained through the remainder of the experiment. Average instantaneous growth rates were lower for contaminant-exposed individuals compared to the reference. There was no difference in mortality between the contaminated and reference treatments.

Executive summary:

Impacts of coal ash contaminated sediment to crayfish Procambarus acutus were studied in non-GLP compliant, non-guideline study. Standard metabolic rates (SMR) of crayfish inhabiting the site contaminated with coal ash were compared with SMR of crayfish from uncontaminated reference sites. Mean SMR was significantly higher for crayfish collected from the contaminated site than for those collected in the uncontaminated reference site. Exposure to contaminated sediments and food for 27 days in the laboratory also led to an increase in SMR, but the difference between treatments was not retained through the remainder of the experiment. Instantaneous growth rates and relative changes in mass in the laboratory reflected trace element exposure. During the first interval of the study (days 0-27), contaminant-exposed individuals experienced significantly lower instantaneous growth rates and relative change in mass (9 vs. 21% change for contaminated and reference, respectively). During the remaining portion of the experiment (days 28-50), average instantaneous growth rates remained lower for contaminant-exposed individuals. During this interval, relative change in mass also remained lower for contaminant- exposed individuals compared to individuals in the reference treatment (11 vs. 27 %), respectively. There was no difference in mortality between treatments at either sampling time (day 27 or 50) in the contaminated and reference treatments, respectively.

Reference 2

Endpoint:

sediment toxicity: long-term

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

July 2000-

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:

Sprint speed and critical swimming speed of juvenile lake chubsuckers (Erimyzon sucetta) exposed to coal ash contaminated sediment was studied in the laboratory.

GLP compliance:

no

Analytical monitoring:

yes

Details on sampling:

Lake chubsuckers were collected from a historically unpolluted Carolina Bay using minnow traps. After transport to the laboratory, fish were allowed to acclimate to laboratory conditions for approximately 4 weeks. During the acclimation period, fish were held in 72-L tanks containing artificial softwater at 25°C and were fed ground Tetramin fish flakes ad libitum.

Test organisms (species):

other: Erizymon sucetta

Details on test organisms:

E. sucetta grazes ground fish food from surface sediments thus ingesting sediments while feeding, which makes it a relevant species for sediment toxicity test. Organisms used in the test were field-collected organisms.

Study type:

laboratory study

Test type:

static

Water media type:

freshwater

Type of sediment:

natural sediment

Duration:

90 d

Exposure phase:

total exposure duration

Test temperature:

25.67 ± 0.08°C and 25.74 ± 0.09°C for test and control treatments, respectively

pH:

7.05 ± 0.04 and 7.20 ± 0.02 for test and control treatments, respectively

Dissolved oxygen:

7.61 ± 0.03 and 7.59 ± 0.02 mg/L for test and control treatments, respectively

Nominal and measured concentrations:

Sediment concentrations were the following (in ppm):
As: 52.10 ± 6.41, Cd: 0.12 ± 0.02, Cu: 71.87 ± 3.19, Se: 6.56 ± 1.07, Sr: 235.97 ± 26.77, V: 56.30 ± 6.04
Water concentrations were the following (in ppb):
As: 38.67 ± 4.45, Cd: 0.31 ± 0.13, Cu: 2.14 ± 0.41, Se: 67.61 ± 19.84, Sr: 463.18 ± 33.41, V: 38.23 ± 10.89

Details on test conditions:

Fish were randomly assigned to individual 38-L experimental tanks containing either weathered coal ash–contaminated sediments or sand (control) (n 12 fish per treatment). The bottom of each tank was covered with approximately 1 cm of substrate, and all tanks were equipped with carbon filters,
heaters (which maintained tank temperatures near 25°C), and aeration. Tanks were arranged in four randomized blocks on laboratory shelves (three replicates of each sediment type per block). On initiation of the study, mean standard length and mass of fish were similar between treatments. Fish were fed ground Tetramin fish food three times per week. Tanks were inspected 4–5 days per week to document fish survival and to monitor
food consumption.

After 78 days of exposure in experimental tanks, sprint speeds (i.e. distance swum divided by the time required to swim the respective distance when starting from a motionless position) of each fish was measured in a 5-m plastic swim track. The track was 4 cm wide, thus encouraging fish to swim unidirectionally and limiting the influence of side-to-side motion on sprint speed estimates. Once a fish remained motionless in the track, they received a single prod with a blunt stainless steel probe on the right side of the caudal peduncle. The procedure was repeated 10–12 times per individual, over a 10–30-min time interval. Sprints occurred over a background marked at 1.0-cm increments and were recorded using a video camera. Following the sprint trial, each fish was weighed and ash-exposed fish were qualitatively ranked in relation to each other based on severity of caudal fin erosion. Fish were returned to their respective experimental tanks following sprint speed trials. The time it took for each individual to swim 5-, 10-, and 20-cm distances was calculated for each sprint. The fastest sprint speed for each individual at each distance was used for statistical comparisons. Fish were allowed to recover from sprint speed trials in their experimental tanks for 12 days before critical swimming speed trials were initiated. Critical swimming speeds were determined using a laminar-flow swim tunnel. Each fish was removed from its holding vessel and placed in the swim tunnel at a water velocity of 2 cm/s. After 30 min, water velocity was increased to 5 cm/s. Critical swimming speed was determined by increasing water velocity in 5 cm/s increments every 30 min. The trial was terminated when the fish rested on the downstream support screen and repeated prods could not stimulate the fish to resume swimming. Critical swimming speeds were determined for one or two fish per day over a 10-day period (n 9 per treatment). At the end of each trial, fish were measured with Morphosys and weighed before being frozen for future lipid and trace element analysis.

Duration:

90 d

Remarks on result:

not measured/tested

Remarks:

The endpoints used in the study included sprint velocity, critical swimming speed, condition factor, nonpolar lipid content, survival, size of fish, degree of fin erosion. No LC-, EC-, NOEC or LOEC values were determined.

Details on results:

At all sprint distances, fish exposed to ash were slower, but the reductions in sprint velocity became more severe in ash-exposed fish as sprint distance increased. Neither condition factor nor nonpolar lipid content of fish influenced speed at any sprint distance. Critical swimming speed was influenced by the interaction between fish standard length and sediment type. Mean critical swimming speed of control and ash-exposed fish was 47.91 ± 3.62 and 24.02 ± 4.29, respectively.
Survival was high and similar among fish in both groups. Control fish were larger than ash fish at termination of the study. Mean condition factor of fish did not differ between treatments. 80% of surviving fish exposed to ash exhibited caudal fin erosion and 70% exhibited pectoral fin erosion, whereas no fin erosion occurred among control fish.
Concentrations of As, Se, Sr, and V were two to eight times higher in ash-exposed fish than in controls. Whole-body concentrations of Cd and Cu were similar in fish from both treatments.

Reported statistics and error estimates:

- Fish exposed to ash for 90–100 days accumulated significant whole body concentrations of trace elements (Pillai’s trace = 0.889, F6,15 = 21.29, p = 0.001
- Control fish were larger than ash fish at termination of the study (control: 57.96±1.00 mm and 4.013±0.19 g; ash: 55.67±1.23 mm and 3.446±0.25 g).
- Mean condition factor of fish did not differ between treatments (t-test, correction for unequal variance; p = 0.302).
- Percent nonpolar lipids in fish did not differ between sediment treatments (control: 7.09±0.68; ash: 6.75±0.48; p= 0.71).
- The presence of caudal fin erosion differed significantly between treatments (p 0.001).
- Sprint speed wassignificantly influenced by sediment type, but this influence was also dependent on sprint distance.
- Neither condition factor nor nonpolar lipid content of fish influenced speed at any sprint distance (in all cases: -0.13< rs< 0.51, p=0.131).
- Based on the ranks of fin erosion severity, caudal fin deterioration also had no effect on sprint speed at any distance measured (0.44 - Mean Ucrit of control and ash-exposed fish was 47.91±3.62 and 24.02±4.29, respectively.
- Linear regression indicated a positive relationship between fish standard length and Ucrit among fish in the control treatment (r2=0.52; p=0.028), whereas there was no relationship between standard length and Ucrit among fish exposed to ash (r2=0.29; p=0.132). Linear regression also indicated a positive relationship between fish mass and Ucrit among fish in the control treatment (r2=0.47; p=0.041), whereas mass of fish exposed to ash had a negative relationship with Ucrit (r2=0.48; p=0.039). Fish condition factor did not influence Ucrit in ash or control fish (rs=–0.55 and –0.17, p=0.125 and 0.668, respectively).Percent nonpolar lipid did not influence Ucrit in ash or control fish (rs=0.55 and 0.05, p=0.160 and 0.911, respectively).Furthermore, caudal fin deterioration had no effect on Ucrit among ash-exposed fish (rs=0.04, p=0.79)

The endpoints used in the study included sprint velocity, critical swimming speed, condition factor, nonpolar lipid content, survival, size of fish, degree of fin erosion. No LC-, EC-, NOEC or LOEC values were determined.

Validity criteria fulfilled:

not specified

Conclusions:

Fish exposed to ash contaminated sediments for 90–100 days accumulated significant concentrations of As, Se, Sr, and V, exhibited severe fin erosion; and had reduced sprint speed and critical swimming speed.

Executive summary:

Sprint speed and critical swimming speed of juvenile lake chubsuckers (Erimyzon sucetta) exposed to coal ash contaminated sediment was studied in the laboratory in a non-GLP-compliant, non-guideline experiment. E. sucetta grazes ground fish food from surface sediments thus ingesting sediments while feeding, which makes it a relevant species for sediment toxicity test. Lake chubsuckers were collected from a historically unpolluted Carolina Bay using minnow traps. After 4 -wk acclimation in the laboratory, fish were transferred to experimental tanks containing either weathered coal ash–contaminated sediments or sand (control). After 78 days of exposure in experimental tanks, sprint speeds and critical swimming speed of each fish was measured. Survival, growth, condition factor, fin erosion and trace element accumulation were also monitored. Fish exposed to ash contaminated sediments for 90–100 days accumulated significant concentrations of As, Se, Sr, and V, exhibited severe fin erosion, and had reduced sprint speed and critical swimming speed. Survival was high and similar among fish in both groups. Control fish were larger than ash fish at termination of the study. Mean condition factor of fish did not differ between treatments.

Reference 3

Endpoint:

sediment toxicity: long-term

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

September 1998-

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:

Lake chubsuckers (Erimyzon sucetta) were exposed to coal ash–polluted sediments under conservative experimental conditions (filtered artificial soft water and abundant uncontaminated food) for 4 months. Mortality, growth, fin erosion concentration of total nonpolar lipids, standard metabolic rate (SMR) and bioaccumulation of trace elements were monitored during the study.

GLP compliance:

no

Details on sampling:

After the final respiratory measurements (124 days) each fish was frozen for later lipid and trace element analysis. In addition, 13 fish captured from the collection site were frozen at the initiation of the study (September) and analyzed with experimental fish for lipids and trace elements. Prior to analysis, each fish was lyopholized and homogenized before being divided into two subsamples. One subsample of each homogenized fish was analyzed for trace element concentrations, and the other subsample was used for lipid analysis. In addition, one sediment sample from each aquarium, nine sediment samples from the collection site, and five samples of Tetramin fish food were analyzed for trace element concentrations

Test organisms (species):

other: Erimyzon sucetta

Details on test organisms:

E. sucetta grazes ground fish food from surface sediments thus ingesting sediments while feeding, which makes it a relevant species for sediment toxicity test. Organisms used in the test were field-collected organisms.Lake chubsuckers were captured from a reference site (collection site) in minnow traps. The collection site was a historically unpolluted Carolina bay. After transport to the laboratory, fish were allowed to acclimate for 5 days in artificial softwater at 25°C. Fish were fed Tetramin fish flakes ad lib during the acclimation period. At the end of the acclimation period, all fish with visible signs of illness or weight loss were excluded from the study.

Study type:

laboratory study

Test type:

static

Water media type:

freshwater

Type of sediment:

natural sediment

Duration:

124 d

Exposure phase:

total exposure duration

Test temperature:

24.62 ± 0.26°C

pH:

7.5 in the ash-treatment, in control pH dropped from 7.5 to 4.3 during the course of the study

Nominal and measured concentrations:

Measured concentrations in the tank were following (in µg/g dry weight);
As: 88.24 ± 2.64, Cd: 0.18 ± 0.01, Cr: 41.01 ± 0.75, Cu: 57.52 ± 0.88, 7.82 ± 0.32, Sr: 380.8 ± 22.60, V: 68.01 ± 0.67

Details on test conditions:

Twenty-four 72-L tanks equipped with carbon filters, heaters, and aeration were utilized in the study. The bottom of each tank was covered with approximately 1 cm of substrate. Half of the tanks received sediment collected from the effluent outflow at the coal ash–polluted site (ash tanks), and the remaining 12 tanks received sand collected from a nearby reference site (control tanks). Sand was collected from an unpolluted terrestrial system and was hand-sifted to remove coarse debris. Tanks contained a 10 x 10 cm clay refugia, which had no bottom to ensure that fish using them maintained exposure to sediments. In the laboratory, tanks were arranged in a randomized block design and one fish was randomly assigned to each tank. Each fish was weighed to the nearest 0.001 g prior to tank assignment. Fish were fed 200 mg of Tetramin fish food every 48 h. Chubsuckers fed by grazing fish food from surface sediments after food was deposited on the bottom of tanks. Thus, fish ingest small quantities of sediment while feeding. Water temperature and dissolved oxygen were monitored at every feeding and pH was measured at the initiation and termination of the study. Tanks were inspected 4–5 days per week for mortality and to document complete food consumption. Brightly colored food was easily detected against the contrasting and uniform background of each sediment type. On days 22, 56, 84, 108, and 124 of the experiment each fish was weighed. In addition, standard metabolic rates (25°C) were determined for each fish on days 0, 84, and 124 of the experiment.

Duration:

124 d

Dose descriptor:

other: Details on results

Remarks on result:

not measured/tested

Remarks:

The endpoints used in the study included growth, survival, fin erosion, standard metabolic rates (SMR), nonpolar lipid (NPL) concentrations. No LC-, EC-, NOEC or LOEC values were determined.

Details on results:

All fish in the control treatment grew and survived to completion of the study whereas fish grazing the ash-contaminated sediments exhibited high mortality (25 %), poor growth rates, and severe fin erosion. By day 60 of the experiment, ash-treated fish exhibited lower body mass compared to fish in the control treatment and the difference remained significant for the duration of the study. Because the feeding regime was constant throughout the study (200 mg/48 h), fish in the control treatment may have ultimately outgrown the feeding regime and become constrained by the experimental
provisions. As a result, fish in the control treatment did not increase in mass for the last 16 days of the experiment. At termination of the experiment, final mean mass of control fish was 41% higher than the mass of ash-treated fish. Moreover, 0% and 25% of fish in the control and ash treatment had died, respectively. In addition, 100% of surviving fish in the ash treatment experienced erosion of the pectoral and caudal fins. In some instances, the caudal fins eroded to the hyperel plate.
Standard metabolic rates did not differ between treatments at initiation of the study or following day 84 and day 124 of experimental exposure. In comparison to nonpolar lipid (NPL) concentrations of fish from the collection site at initiation of the study, fish in both treatments exhibited increases in NPL by the end of experimental manipulations. Control fish stored twice as much energy in the form of NPL, however, total NPL did not differ between treatments when fish mass was considered using ANCOVA In addition, percent NPL did not differ significantly between treatments.

Reported statistics and error estimates:

- Trace element concentrations in the sediments differed significantly between collection site, control tanks, and ash-treated tanks (As: F2,30=2020.78, p<0.001; Cd: F1,19=42.25, p<0.001; Cr: F2,30=760.84, p<0.001; Cu: F2,30=765.29, p<0.001; Se: F1,19=270.60, p<0.001; Sr: F2,30=579.70, p <0.000; V: F2,30=1,370.10, p<0.001).
- When compared to initial whole-body concentrations, levels of Se and Sr increased significantly in ash-exposed fish and decreased significantly in control fish (Se: F2,31=321.18, p<0.001; Sr: F2,31=215.18, p<0.001). Increases in As burdens were not statistically significant in ash-exposed fish, but concentrations actually decreased significantly in control fish (F2,31=16.61, p<0.001). Although V concentrations increased significantly in both treatments, the increase was significantly higher in ash-exposed fish (F2,31=201.36, p<0.001).
- Copper levels decreased to a greater extent in the control treatment than in the ash treatment (F2,31=54.86, p<0.001). On the other hand, Cd levels actually decreased in the ash-treated fish but did not decrease significantly in control fish (F2,31=13.12, p<0.001). Although Cr levels decreased in
fish from both treatments, the decrease was not statistically significant (F2,31=2.42, p=0.106).
- 0% and 25% of fish in the control and ash treatment had died, respectively (p=0.217).
- Control fish stored twice as much energy in the form of NPL (p<0.001), however, total NPL did not differ between treatments when fish mass was considered using ANCOVA (LS means: ash=0.328±0.021, control=0.328±0.015; p=0.996). In addition, percent NPL did not differ significantly between
treatments (p=0.114).

The endpoints used in the study included growth, survival, fin erosion, standard metabolic rates (SMR), nonpolar lipid (NPL) concentrations. No LC-, EC-, NOEC or LOEC values were determined.

Validity criteria fulfilled:

not specified

Conclusions:

Ash-derived pollutants were toxic to fish. Twenty-five percent of fish exposed to pollutants died during the study. All surviving fish exposed to ash exhibited substantial decreases in growth and severe fin erosion. Total nonpolar lipids were two times higher in fish from the control treatment, but percent lipid did not differ between treatments. However, there were no differences in standard metabolic rates of fish between the treatments.

Executive summary:

Toxicity of ash-derived pollutants to fish was studied in non-GLP compliant, non-guideline laboratory study. Lake chubsuckers (Erimyzon sucetta) that graze on sediment surface were exposed to coal ash–polluted sediments under conservative experimental conditions (filtered artificial soft water and abundant uncontaminated food) for 4 months.Mortality, growth, fin erosion concentration of total nonpolar lipids, standard metabolic rate (SMR) and bioaccumulation of trace elements were monitored during the study.

Twenty-five percent of fish exposed to pollutants died during the study. All surviving fish exposed to ash exhibited substantial decreases in growth and severe fin erosion. Total nonpolar lipids were two times higher in fish from the control treatment, but percent lipid did not differ between treatments. Because fish were presented with the same amount of food during the study, it appears fish exposed to ash utilized more energy for daily activities and/or were less efficient at converting available energy to tissues for growth and storage. The results were particularly interesting because there were no differences in standard metabolic rate (SMR) of fish between treatments. Increased energy expenditures not detectable in estimates of maintenance based on SMR, such as costs of digestion or activity, may have contributed to decreased energetic efficiency.

Reference 4

Endpoint:

sediment toxicity: long-term

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.

Reason / purpose for cross-reference:

reference to same study

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 and glutathione concentration in clam tissue, shell growth, and condition index were assessed at five sites along a contamination gradient.

GLP compliance:

no

Remarks:

A WOE study published in 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 five study sites. 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. Additional two clams from each cage were collected at each date for GSH analysis from Site A and reference site. Digestive glands from transplanted and resident clams were immediately dissected after returning from the field and stored at -70°C until analysis. Clams were weighed and measured (length, width, and depth) and the shell volume was calculated using the formula for an ellipsoid. Condition index (g dry tissue mass/cm3 volume) in transplanted clams among the study sites on all dates were determined. On each sampling date, water and sediment from all sites 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.

Details on sediment and application:

Sediments were collected from five sites located on the US Department of Energy's Savannah River Site near Aiken, USA. The contaminated study stream, Beaver Dam Creek, is located near a coal-fired power plant that has been operating since 1952. 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.

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.

Study type:

field study

Test type:

other: field study

Water media type:

freshwater

Type of sediment:

natural sediment

Duration:

84 d

Exposure phase:

total exposure duration

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)

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 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.

Duration:

84 d

Remarks on result:

not measured/tested

Remarks:

Endpoints used in the study included mortality, growth rate, and condition index. No LC-, EC-, NOEC or LOEC values were determined.

Details on results:

Clam mortality was less than 1 % during the study. Clams from Site A had the highest growth rate (0.040 mm/day) and condition index (0.006 g DM/cm3, day 84). Clam growth rate was significantly higher at Site B (0.011mm/day) than at the reference site (0.001mm/day), but significantly lesser than at Site A (0.040 mm/day). However, water temperatures varied significantly among sites and log[growth rate] increased with mean temperature across all sites (r2 = 0.68, p < 0.0001). GSH concentrations in transplanted clams were significantly higher at Site A than at the reference site at the completion of the study.

Reported statistics and error estimates:

- 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).
- Clam growth rate was significantly higher at Site B (0.011mm/day) than at the reference site (0.001mm/day), but significantly lesser than at Site A
(0.040 mm/day). However, water temperatures varied significantly among sites (p < 0.0001) and log[growthrate] increased with mean temperature across all sites (r2 = 0.68, p < 0.0001).

Endpoints used in the study included mortality, growth rate, and condition index. No LC-, EC-, NOEC or LOEC values were determined.

Validity criteria fulfilled:

not specified

Conclusions:

Clams at the most contaminated site had the highest growth rate, condition index and glutathione concentrations.

Executive summary:

Impacts of sediments contaminated with coal-fired power plant discharge on clams Corbicula fluminea were studied in a non-GLP compliant, non-guideline chronic field study. Clams were transplanted from a reference stream to a stream receiving coal-fired power plant discharge. Trace element accumulation and glutathione (GSH) concentration in clam tissue, shell growth, and condition index were assessed at five sites along a contamination gradient. Clam mortality was less than 1 % during the study. Clams from the most contaminated study site had the highest growth rate (0.040 mm/day) and condition index (0.006 g DM/cm3, day 84). Also, GSH concentrations in transplanted clams were significantly higher at the most contaminated site than at the reference site at the completion of the study. It was assumed that the highest temperature and richest food supplies at the most contaminated site masks the effects of the contaminants.

Reference 5

Endpoint:

sediment toxicity: short-term

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Non-GLP compliant, non-guideline experimental investigation adopting a standard method. Study published in scientific, peer reviewed journal.

Principles of method if other than guideline:

A 7-day laboratory toxicity tests with the fathead minnow (Pimephales promelas) embryo/larvae and coal ash contaminated sediment. Adopted US EPA method Short-term methods for estimating the chronic toxicity of effluent and receiving waters to freshwater organisms (US EPA/821/R/02/013).

GLP compliance:

no

Remarks:

A WOE study published in peer reviewed scientific journal

Details on sampling:

Sediment samples were collected using a box corer and and VibeCore-D. Samples consisting of the top six inches of sediment were stored at ≤4°C in the dark for up to 60 days until testing for toxicity.

Control/test water was obtained from the upstream reference site prior to the initiation of toxicity tests. Water was pre-filtered with a 0.45 µm pore-size filter to remove large particulates, sterile-filtered at 0.2 µm prior to storage at ≤4°C in the dark, and then adjusted to test temperature before use.

Test organisms (species):

other: Fathead minnow embryo/larvae

Details on test organisms:

Fathead minnow embryos\6 h old were obtained from in-house stock cultures on the morning of each test.

Study type:

laboratory study

Test type:

static

Water media type:

freshwater

Type of sediment:

natural sediment

Duration:

7 d

Exposure phase:

total exposure duration

Post exposure observation period:

No

Hardness:

54 - 60 mg/L as CaCO3

Test temperature:

25 ± 1°C

pH:

7.3 - 7.6, test discard water 7.6 - 7.8

Dissolved oxygen:

8.2 - 8.6 mg/L, test discard water the same values

Salinity:

No data

Ammonia:

No data

Nominal and measured concentrations:

Proportion of ash containing sediment in the test sediments: 100 %, 75 %, 50 %, 25 %, 0 % ("concentration series").
Additional water chemistry data: alkalinity 48-53 mg/L, conductivity 128-135 µS/cm.
For other values see Table 1.

Details on test conditions:

Prior to testing, sediment samples were mixed with a stainless steel drill attachment to reincorporate pore-water, then a concentration series was prepared for testing purposes by diluting ash-containing sediment samples with ash-free reference sediment. Approximately 35 mL of each sample at the various test concentrations was layered on the bottom of four replicate 185-mL polystyrene dishes and then overlaid with 100 mL of test water; control chambers contained 135 mL of test water only. Test chambers were loosely covered and sediment was allowed to settle overnight, following which levels were adjusted to provide a final 1:3 sediment-to-water ratio by volume.

Following randomization, 15 embryos were carefully deposited directly on the surface of the settled sediment layers in each test chamber. For each test, embryos and larvae were exposed according to standard test guidelines for 7 days through the absorption of the larval yolk sac. Photoperiod was 16-h light: 8-h dark.

Approximately 60 % of the test water was replaced daily in test chambers, with care taken to minimize disturbance of the bottom sediment layer. Embryos were scored daily for survival, hatching success, and developmental abnormalities, following which dead embryos/larvae were removed and discarded. Abnormality test endpoints included failure to hatch, lack of mobility, skeletal abnormalities such as spinal curvature, stunted growth, fin abnormalities, abnormal eye development, circulatory abnormalities, pronounced and persistent edema, and jaw and other craniofacial abnormalities. At test termination, an overdose of a fish anesthetic, tricane methanesulfonate (MS-222), was added to each test chamber to euthanize the remaining test organisms. Embryos/larvae were then removed with a transfer pipette and placed in clear polystyrene dishes for final scoring of survival and incidences of developmental abnormalities, followed by archival storage in formalin. The primary test endpoint was total mortality which included dead as well as live but deformed embryos and larvae at test termination.

Duration:

7 d

Dose descriptor:

NOEC

Effect conc.:

ca. 100 other: %

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Duration:

7 d

Dose descriptor:

other: EC25

Effect conc.:

ca. 100 other: %

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Details on results:

Neither embryo-larval survival, incidences of developmental abnormalities, nor hatching success were adversely affected by either full-strength ash-containing sediment or the reference sediment, nor were significant differences observed within the corresponding full dilution series for any of the four ash-containing sediment samples (NOEC = 100 % and EC25≥100 % in each case: detailed test data not shown). Tendencies for slight reductions in embryo-larval survival in test chambers with either reference or coal ash-contaminated sediment compared with control water alone were noted (Fig. 2). However, such minor reductions in survival were neither statistically significant nor totally unexpected given that the embryos became coated with sediment very relatively early in the tests.

Reported statistics and error estimates:

Hatching success, incidences of deformities, and embryo-larval survival/mortality were compared between ash-free reference and ash-containing sediments by one-way ANOVA and a Holm–Sidak pair-wise comparison procedure at p<0.05. The EC25 (concentration at which a 25 % reduction in survival is expected) was determined for each concentration series by Probit Analysis. A no observed-effect concentration (NOEC) was calculated from arc sine-transformed data with Dunnett’s procedure or Steel’s rank test based on the results of a prior Shapiro– Wilk’s test for normality and a Bartlett’s test for homogeneity of variance.

Table 1 Percent ash and concentrations and speciation of selected metals/metalloids in Emory River sediment samples tested for embryo-larval toxicity following the TVA Kingston Fossil Fuel Plant coal ash release

Analyte^a	A	B	C^b	D	Reference
% Ash	67	75	78	46	-
Total arsenic	59	84	83	46	3
Inorganic arsenic	59	73	N/A	55	2
Arsenite	7	3	N/A	23	≤0.2^c
Arsenate	52	70	N/A	32	2
Total selenium	4	10	5	4	≤0.7^c
Selenite	3	6	N/A	2	≤1^c
Selenate	≤0.7^c	≤0.6^c	N/A	≤0.8^c	≤0.8^c
Organic selenium	1	4	N/A	2	1
Total mercury	82	145	180	109	28
Methyl mercury	0.02	≤0.01^c	N/A	≤0.01^c	0.32
Inorganic mercury	81	145	N/A	109	28

^a Metals/metalloids expressed as mg/kg dry weight, with the exception of mercury at lg/kg dry weight

^b Metal/metalloid speciation analyses were unavailable for this sediment sample

^c Values equal analysis detection limits

Conclusions:

Contaminated sediment containing up to 78 % coal ash had no effects on mortality, hatching and developmental abnormalities of Fathead minnow embryos and larvae.

Executive summary:

The early development of Fathead minnow (Pimephales promelas) embryos and larvae during contact exposures to river bottom sediments containing up to 78 % coal ash from the Kingston spill was examined in 7-day non-GLP compliant, non-guideline laboratory study. The contaminated sediment contained selenium and arsenic with known toxicity to fish early life stages, and mercury. Total concentrations were for arsenic 46 - 84 mg/kg d.w., for selenium 4 -10 mg/kg d.w, and for mercury  82 - 180 µg/kg d.w. Total arsenic comprised primarily of inorganic arsenate. Total selenium consisted primarily of organic selenium and selenite. Inorganic forms were the predominating forms of mercury. No significant effects were observed in hatching success, incidences of developmental abnormalities, or embryo-larval survival.

Description of key information

Sediment toxicity of ash was estimated based on five publications from literature. All publications were based on non-GLP, non-guideline experiments. Four of them were conducted using organisms feeding on sediment surface, exposing them to coal ash contaminated natural sediment and measuring e.g. growth, standard metabolic rates (SMRs) and condition factors. Test organisms included clam (Corbicula fluminea), crayfish (Procambarus acutus) and benthic fish (Erimyzon sucetta). All organism were found to accumulate trace elements. Sublethal effects varied among the test species being most severe in benthic feeding fish. Additionally, 25 % of fish were killed in the ash-treatment. One study on benthic fish (Pimephales promelas) embryo/larvae studying mortality, hatching success and developmental abnormalities when exposed to coal ash contaminated sediments. Differences in mortality were not observed between test and control groups for clam, crayfish or fish embryo/larvae. Also, unsuccessful hatching or developmental abnormalities were not observed in fish embryo/larvae. 

Additional information

Adverse effects of coal ash-derived contaminants were estimated based on mortality, growth, condition index and standard metabolic rate (SMR) for three test species in long-term tests. No mortality was observed for clam or crayfish. In the first fish test no mortality was observed, while in the second fish test 25 % of fish died. Severe skin erosion was observed in fish in both tests, however. Growth was reduced in ash-treatment for fish and crayfish but the clams grew better in contaminated environment. This was assumed to be due to masking effect of higher temperature and richer food supplies at the most contaminated site. SMRs were significantly higher for indogenous crayfish inhabiting the contaminated sediment, compared to crayfish from uncontaminated reference site. In laboratory exposure, the effects were not as obvious. For fish, there were no differences in standard metabolic rates of fish between the treatments. Neither were there differences in mean condition factors. Adverse effects were, however, detected in sprint speed and critical swimming speed. When fish embryos/larvae were exposed to sediment contaminated with up to 78% of coal ash in a laboratory test, mortality, unsuccessful hatching or abnormal development was not observed. The contaminated sediment contained metals and metalloids known to be toxic to fish early life stages.