Brachionus
- Brachionus angularis
- Brachionus calyciflorus
- Brachionus patulus
- Brachionus plicatilis
- Brachionus rubens
- Brachionus urceolaris
Freshwater species.
[ref. ID; 1264]
Test system
96-hr acute toxicity
Strains
From Ft. Loudoun Reservoir in March, 1972. Immature female, young female wihout egg, egg-bearing female.
Toxicants
Water-soluble or water-emulsifiable commercial formulations of 2,4,5-T (Line Rider Amine 4T, Veon 245, Line Rider 4T, Dacamine 4T, Lo-Vol 4T, and Lo-Vol 6T).
Test design
Temperature 20 degrees C. Food: Chlorella sp. or Cryptomonas sp. Sampling time: 12, 24, 48, 72, and 96 hr.
Measurements/observations
Mean remaining length of life (days), mean time to hatch (days), and mean longevity.
Evaluations
LC50.
Freshwater species.
[ref. ID; 107]
Test system
48-hr acute toxicity
Strains
Collected from the local pond.
Toxicants
Furadan-3G, Malataf-50E.
Test design
Petri dish (medium: filtered pond water, hardness 96 mg CaCO3/l, alkalinity 112 mg CaCO3/l, Calcium as Ca+ 28.5, pH 8.6, Dissolved oxygen 9.5 mg/l), triplicates of each concentration. Temperature 25.3-25.8 degrees C.
Measurements/observations
Numbers of affected organisms.
Evaluations
EC50.
[ref. ID; 111]
Test system
24-hr acute toxicity test
Strains
Cysts from Dr. Snell (University of Tampa. U.S.A.).
Toxicants
Organochlorine endosulfan 96% (Hoechst Iberica S.A., Spain) (carrier acetone), Organophosphates diazinon 92% (Cequisa S.A., Spain) (carrier acetone) Methylparathion 80% (Bayer Hispania S.A.) (carrier acetone), Malathion 95% (American Cyanamid Co.) (carrier acetone), Carbamate benthiocarb 93% (Argos S.A., Spain) (carrier acetone).
Test design/concentrations
Temperature 25 degrees C. 24-well plates (EPA medium: NaCO3 96 mg/l, CaSO4/2H2O 60 mg/l, MgSO4 60 mg/l, KCl 4mg/l, pH 7.4-7.8, hardness 80-100 mg CaCO3/L, alkalinity 60-70 mg/L), darkness, no food, six concentration (including control).
Measurements/observations
Survival numbers.
Evaluations
LC50 using "moving-average" analysis.
[ref. ID; 121]
Test system
Chronic toxicity (2-days life cycle test)
Strains
Brachionus calyciflorus Pallas, originally collected in Gainesville, Florida, in 1983.
Toxicants
Copper (atomic absorption standard solution), Cadmium (atomic absorption standard solution), 2,4-dichlorophenoxyacetic acid (2,4-D), phenol, Sodium pentachlorophenol (NaPCP), Xylene, 2,4-dimethyl phenol, Diazinon, Chlorpyrifos (Dursban).
Test design/concentrations
Temperature 25 degrees C. 16x150 mm glass tube (EPA medium: NaHCO3 96 mg/l, CaSO4/2H2O 60 mg/l, MgSO4/7H2O 60 mg/l, KCl 4mg/l, pH 7.5), darkness, rotating, with food (Nannochloris oculata), 5 toxicant concentration + control, 5 replicates.
Measurements/observations
The intrinsic rate of population increase (r).
Evaluations
NOEC, LOEC, Chronic value.
[ref. ID; 127]
Test system
Effect of cyst age, temperature, and salinity on the acute toxicity
Strains
Brachionus calyciflorus Pallas, originally collected in Gainesville, Florida, in 1983.
Toxicants
Acetone, Benzene, Chloroform, Hexane, Toluene, Xylene, Sodium dodecyl sulfate (SDS), Sodium Pentachlorophenol (NaPCP), 2,4-dichlorophenoxyacetic acid (2,4-D), Fenitrothion, 1-Chloro-2,4-dinitrobenzene (CDNB), Chlorpyrifos, 3,4-Dichloroaniline, Diesel fuel, Phenol, Trichlorofon, Sodium hypochlorite (NaOCl), NH4Cl (Free ammonia), Aluminium, Cadmium (atomic absorption standard solution), Copper (atomic absorption standard solution), Lead (atomic absorption standard solution), Mercury (atomic absorption standard solution), Nickel (atomic absorption standard solution), Tributyl tin, Selenium (atomic absorption standard solution), Silver (atomic absorption standard solution), Zinc.
Test design
24-well polystyrene plate (EPA medium: NaHCO3 96 mg/l, CaSO4/2H2O 60 mg/l, MgSO4 60 mg/l, KCl 4mg/l, pH 7.5 & ASPM medium: NaCl 5.28 g/l, KCl 0.17 g/l, CaCl2 0.25 g/l, MgCl2/6H2O 0.92 g/l, MgSO4/7H2O 1.12 g/l, NaHCO3 0.08 g/l, pH 7.5, salinity 7 ppt), darkness.
- Cyst age: 0-18 months.
- Temperature: 10, 15, 20, 25, 30 degrees C.
- Salinity: Standard freshwater, deionized water, standard seawater of salinities of 2-10 ppt.
Measurements/observations
Number of live and dead animals.
Evaluations
LC50 by probit analysis using Statview II.
[ref. ID; 128]
Test system
24-hr acute lethal toxicity
Strains
Cysts.
Toxicants
Fenitrothion, Chlorpyrifos, 3,4-Dichloroaniline (3,4-DCA), Trichlorfon, Lindane.
Test design/concentrations
Temperature 25 degrees C. 24-well polystyrene tissue plate (EPA medium: NaHCO3 96 mg/l, CaSO4/2H2O 60 mg/l, MgSO4 60 mg/l, KCl 4mg/l, pH 7.4-7.8, hardness 80-100 mg as CaCO3/L, alkalinity 60-70 mg/L), darkness, no food. Six concentrations (including control) for one acute toxicity test x 3 replicates.
Measurements/observations
Survival data.
Evaluations
LC50 calculated using "moving-average" analysis.
[ref. ID; 192]
Test system
Sublethal toxicity tests
Strains
Cyst.
Toxicants
Diazinon.
Test design/concentration
Temperature 25 degrees C. 24-well polystyrene plates (EPA medium: NaCO3 96 mg/l, CaSO4/2H2O 60 mg/l, MgSO4 60 mg/l, KCl 4mg/l, pH 7.4-7.8, hardness 80-100 mg as CaCO3/L, alkalinity 60-70 mg/L as CaCO3), darkness, with food (Nannochloris oculata 5x10E5 cell/L).
24-hr LC50 tests were conducted using a wide concentration range of diazinon (0-50 mg/L). The 24-hr LC50 obtained was 29.22 mg/L. Based on this, diazinon levels of 0 (control), 5, 7, 14, 19 mg/L (0, 1/5, 1/4, 1/2 and 2/3 of the 24-hr LC50).
Measurements/observations
Number of attached eggs, offspring and mortality.
Evaluations
LC50 and EC50 (survivorship (lx), life expectancy at hatching (eo), fertility (mx), net reproductive rate (Ro: multiplication rate per generation), generation time (T: mean period elapsing between the birth of parent and the birth of its offspring), intrinsic rate of natural increase (r: population grown per individual), reproductive value (Vx: contribution to the future population).
[ref. ID; 504]
Test system
Acute toxicity (24-hr)
Strains
Brachionus calyciflorus kits (Toxkits).
Toxicants
- CuSO4/5H2O (six concentrations, five replication).
- [CuSO4/5H2O 0.08 mg/l]:[Fulvic acid of freshwater origin from the Rio Santiago] 1:0, 1:0.25, 1:0.5, 1:1, 1:2.
Experimental conditions
Temperature 25 degrees C. Multiwell plates using 10 neonates (less than 2 hr old) per treatment.
Measurements
Immobility.
Evaluations
- Cu(II): LC50 (by means of the best-fit dose-response curve with the Grandpro program).
- Cu(II)/FA: Arcsine transformation was applied to each result, to ensure homoscedasticity before analysis of variance (ANOVA).
[ref ID; 510]
Test system
The effect of short-term exposure to xenobiotics on the feeding behavior
Strains
Originally collected in Gainesville, Florida. Hatching cysts were hatched at 25 degrees C in light (6000 lux) in a synthetic freshwater (EPA water). Neonates were collected 16-18 hr after the initiation of the hatching and used in the experiments. Food: Nannochloris oculata 5x10E5 cells/ml.
Toxicants/concentrations
CuSO4 (0.05, 0.08, 0.1, and 0.25 mg/liter), pentachlorophenolate (0.5, 1.0, 2.0, and 5.0 mg/liter), 3,4-Dichloroaniline (3,4-DCA) (30, 40 50 and 60 mg/liter), and Lindane (2, 5, 10, and 15 mg/liter).
Test design
In 8-ml glass vials containing 5 ml of the test solution. 30 rotifers/ml in nonrotating vials, in darkness at 25 degrees C. Exposure period 5 hr. 5 replicates.
Measurements/observations
Filtration rate and ingestion rate.
Evaluations
EC50.
[ref. ID; 954]
Test system
Population dynamics of rotifers and its concequence for ecotoxicology
Strains
Strain T3/II from fishpond T3 at Winterhausen new Wurzburg in July 1968.
Measurements/observations
Population parameter's (intrinsic rate of natural increase (r), carrying capacity (K), and frequency (f).
[ref. ID; 1317]
Test system
Swimming activity, acute toxicity & chronic toxicity
Strains
Brachionus calyciflorus Pallas, originally collected in Gainesville, Florida.
Toxicants
Copper, Sodium pentachlorophenol, 3,4-dichloroaniline, lindane.
Test design/concentrations
Temperature 25 degrees C. Medium (a moderately hard (100 mg/liter CaCO3) synthetic freshwater medium)
- Swimming activity test: A shallow, circular polystyrene chamber (diameter 23.5 mm, depth 1.2 mm); observations were made after 5, 10, 20, 30, 60, 120, 180 and 300 min. Activity was recorded as the number of squares entered in a 30-sec observation period (sq/30).
- Acute toxicity test: Acute toxicity test were conducted using 24-well polystyrene plates, three replicates of 10 rotifers, five toxicant concentration.
- Chronic toxicity test: 24-well polystyrene plates, four replicates, food (Nannochloris oculata 5x10E5 cells/ml).
Measurements/observations
Swimming activity, mortality, intrinsic rate.
Evaluations
EC50 (swimming activity, survivorship (lx), fertility (mx), intrinsic rate of natural increase (r)), LC50, LOEC, NOEC.
[ref. ID; 1532]
Test system
Strains
Strain S-4 (Starkweather, 1981). Food: Euglena gracilis (strain E-753).
Toxicants
Microcystis aeruginosa (NRC-SS-17).
Test design
Food type (NRC-SS-17 20 ug ml-1, E-753 20 ug ml-1, and No food) x Medium (Fresh and Conditioned).
'Fresh' medium was autoclaved and filtered (Whatman GF/C) ASM-1-TR which stored for daily use at 4 degrees C.
'Conditioned' medium was ASM-1-TR in which M. areuginosa had been grown for 6-8 days, the cells by gentle centrifugation and filtered the supernatant through GF/C filters.
20-22 degrees C, continuous illumination. 3 replicates.
Measurements/observations
Median survivorship, reproductive rate, generation time, and rate of population increase.
Evaluations
Treatment effects using the non-parametric Kruskal-Wallis test corrected for ties (Sokal & Rohlf, 1981).
[ref. ID; 1547]
Test system
Changes in the swimming behavior-, feeding-, and demographic characteristics
Strains
Originally collected in Gainesville, Florida, USA. Food: Nannochloris oculata.
Toxicants
CuSO4/5H2O.
Test design
Cysts were hatched at 25 degrees C in light (6000 lux) in synthetic freshwater. Temperature 25+/-0.5 degrees C. EPA water (96 mg NaHCO3, 60 mg CaSO4/2H2O, 60 mg MgSO4 and 4 mg KCl in one liter of deionized water, adjusted to pH 7.8).
- Swimming activity: A single 0-2 hours old neonates were transferred into a shallow, circular polystrene chamber (diameter 23.5 mm; depth 1.2 mm) containing 0.7 ml medium (control, 6, 12, 25, 60, 120, and 250 ugCu l-1) for periods ranging from 5 minutes to 5 hours without food. The swimming activity of <2 hours old rotifers is not significantly affected by the presence of different food concentrations in the range of 0 to 5x10E6 cell ml-1.
- Feeding activity: In 8 ml glass vials containing 5 ml of the treatment solution (control, 12, 20, 25, and 60 ugCu l-1) with 30 rotifes ml-1 and an initial food concentration of 5x10E5 cells ml-1 of Nannochloris oculata. The neonate (0-2 hr old) were allowed to feed for 5 hours.
- Demographic parameters: One neonates (0-2 hour old) was introduced in each of the wells (sterile, 24-well polystyrene plates) containing 1 ml of test solution (0, 1.2, 2.5, 5.0 and 10 ugCu l-1). Each rotifer was checked every 12 hours and the number of attached eggs, offspring, and mortality recorded. The parent female was transferred into fresh medium every 24 hours. The food density 5x10E5 cells ml-1 Nannochloris. Tests were terminated when the last individual of every cohort had died.
Measurements/observation
- Swimming activity: Under the chamber a grid with 1 mm squares was placed, the number of 1mm squares entered in 30 seconds.
- Feeding activity: Final food concentration using a hemacytometer.
- Demographic parameters: At every age (x), the survirvorship (lx) and fertility (mx) tables were constructed using standard methods (Poole 1974; Southwood 1976) and the following demographic parameters were calculated: net reproductive rate (Ro), generation time (T), life expectancy (eo) and the intrinsic rate of natural increase (r).
Evaluations
EC50's (the concentration of the toxicant that reduces the test parameter to 50%) were calculated using probit analysis (Finney 1971). To determine statistically significant differences between groups a one-way analysis of variance was used. Mean separation was accomplished by Duncan's multiple range test.
[ref. ID; 1592]
Test system
To establish the relative contribution of the direct and indirect (trophic) pathways to PCB contamination of Zooplankton living in the river Meuse (Belgium).
Strains
Food: Dictyosphaerium ehrenbergianum
Toxicants
Aroclor 1260.
Test design
- Direct pathway: One hundred thousand rotifers were placed in 1.5 l of Volvic water containing PCB concentrations varying from 0.06 to 3 ug of Aroclor l-1. The glass vessels were hermetically closed and placed on a magnetic stirrer. With and without humic acid (3 mgC l-1). A 24-hour incubation at room temperature.
- Trophic pathway: Ingestion (food concentration 0.12~1.18 mgC l-1 x temperature 15 and 20 degrees C), assimilation, and elimination rates measurements were based on the radiotracer (NaH[14]Co3) technique.
- Food: PCB contaminated algae Dictyosphaerium ehrenbergianum (5 ug Aroclor 1260 l-1 of culture medium).
Measurements/observations
PCBs concentration in rotifers.
[ref. ID; 1666]
Test system
24-hr acute toxicity & chronic toxicity
Strains
Cysts from Dr. Snell (University of Tampa, U.S.A.).
Toxicants
Lindane, 3,4-dichloroaniline.
Test design
Temperature 25 degrees C. 24-well polystyrene plates (EPA medium: NaHCO3 96 mg/l, CaSO4/2H2O 60 mg/l, MgSO4 60 mg/l, KCl 4mg/l, pH 7.4-7.7, hardness 80-100 mg CaCO3/l, alkalinity 60-70 mg/L), darkness, with food (Nannochloris oculata 5.0x10E5 cells/ml).
Measurements/observations
Survival.
Evaluations
LC50, EC50 (survivorship (lx), life expectancy at hatching (eo), fertility (mx), net reproductive rate (Ro), mean generation time (T), intrinsic rate of natural increase (r), reproductive value (Vx).
[ref. ID; 1667]
Test system
24-hr acute toxicity & chronic toxicity
Toxicants
Methylparathion.
Test design
EPA medium (NaHCO3 96 mg/l, CaSO4/2H2O 60 mg/l, MgSO4 60 mg/l, KCl 4mg/l: pH 7.4-7.8: hardness 80-100 mg CaCO3/l: alkalinity 60-70 mg/L), darkness. Temperature 25 degrees C. Food; Nannochloris oculata (5.0x10E5 cells/ml) and Chlorella pyrenoidosa (5.0x10E5 cells/ml).
Measurements/observations
Survival.
Evaluations
LC50 and EC50 (survivorship (lx), life expectancy at hatching (eo), fertility (mx), net reproductive rate (Ro), generation time (T), intrinsic rate of natural increase (r), reproductive value (Vx/Vo).
[ref. ID; 1717]
Test system
Chronic toxicity (2-days whole life cycle bioassay)
Strains
Cysts from Bioresponse Systems, Inc. (Halifax, NS, Canada).
Toxicants
Cationic surfactants (N-octyl trimethyl ammonium chloride, N-dodecyl trimethyl ammonium chloride, N-hexadecyl trimethyl ammonium chloride, N-alkyl (dodecyl-tetradecyl mix)-N-hydroxyethyl dimethyl ammonium chloride), Amine compounds (N,N-octyl dimethyl amine, N,N-dodecyl dimethyl amine), Anionic surfactants (Linear alkylbenzene sulfonate, Mono-n-dodecyl phosphate, Sodium dodecyl sulfate, Sodium 1-dodecane sulfonate, Sodium tetradecyl sulfate, Sodium dodecyl dioxyethylene sulfate, Sodium dodecyl tetraoxyethylene sulfate, Sodium tridecyl dioxyethylene sulfate, Sodium tetradecyl tetraoxyethylene sulfate, Sodium pentadecyl tetraoxyethylene sulfate), Nonionic surfactants (Dodecyl trioxyethylene ether), Other polar compounds (n-dodecanol, n-dodecanoic acid), Copper (cupric sulfate), Pentachlorophenol (PCP).
Test design
Temperature 25+/-2 degrees C. Photoperiod 16L:8D cycle. Rotator (1/5 rpm), pH 8.6, D.O. 8.5, hardness 152 mg/L as CaCO3, conductivity 450 umhos. Food: Chlorella vulgaris, Selenastrum capricornutum (1.0x10E6 cells/ml). 3 replicates.
Measurements/observations
Number of live, swimming animal.
Evaluations
EC20, EC50.
[ref. ID; 1973]
Test system
24 hr acute toxicity test (B. calyciflous (prey) and Asplanchna sieboldi (predator) interaction)
Strains
Originally isolated from Lake Chapultepec in Mexico city.
Toxicants
Methylparathion.
Test design
Temperature 25 degrees C. 25-ml capacity transparent vials containing 20 ml EPA medium, with food (Chlorella vulgaris (0.25x10E6 cells/ml)). Continuous diffused fluorescent illumination.
Measurements/observations
Mortality.
Evaluations
LC50.
[ref. ID; 2168]
Test system
2-day reproductive test
Strains
Originally collected in 1983 in Gainesville, Florida.
Toxicants
Cadmium (atomic absorption), Sodium pentachlorophenate, Chlorpyrifos, Naphthol.
Test design
Temperature 25 degrees C. 16x120 mm glass tube (medium: synthetic freshwater), rotation (10-15 revolutions/hour), darkness, with food (Nannochloris oculata), 4 replicates.
Measurements/observations
Number of ovigerous sexual female and ovigerous asexual female, eggs, male and nonovigerous female.
Evaluations
NOEC, LOEC, EC (intrinsic rate of natural increase (r)).
[ref. ID; 3330]
Test system
Acute toxicity (effect of fluid motion) and 2-days reproduction test
Strains
Originally collected in 1983 in Gainesville, Florida (Snell et al., 1991), neonate females (4-6 hr old).
Toxicants
NaPCP.
Test design/concentrations
Temperature 25 degrees C. EPA medium (NaHCO3 96 mg/l, CaSO4/H2O 60 mg/l, MgSO4 60 mg/l, KCl 4mg/l, pH 7.5), darkness, with or without food (Nannochloris oculata 2.0x10E6 cells/ml).
- Acute toxicity test: Polystyrene cell culture flasks (including 12 ml test volume in 30 ml containers): 6 concentrations (0, 190, 330, 450, 600, and 750 ug/l) x 7 fluid motion treatments per PCP exposure (0, 1, 5, 10, 20, 30 and 40 oscillations/min) x 4 replicates, no food.
- 2-days test; Polystyrene cell culture flasks (including 12 ml test volume in 30 ml containers): 6 concentrations (0, 60, 110, 190, 330, or 450 ug/l) x 4 replicates, with food.
Measurements/observations
Mortality, reproduction rate.
Evaluations
EC50, LC50, NOEC, LOEC: two-way analysis of variance and Dunnett's test was used to assess the individual effects of fluid motion or PCP exposure on reproduction.
[ref. ID; 4957]
Test system
Sublethal toxicity tests (age-specific response and effect of food level)
Strains
Originally isolated from the principal canal of Lake Xochimilco, Mexico City, Mexico. Clonal populations were established for 2 years using the green alga Chlorella vulgaris (registered strain no. CL-V-3, Algal Stock Culture Department of CICESE, Ensenada, Baja California, Mexico) as the exclusive food.
Toxicants
HgCl2
Test design/concentrations
The experiments were conducted in 25 ml glass jars containing 20 ml medium containing one of the five toxicant concentrations (0, 0.625, 1.25, 2.5 and 5.0 ug/l) at the chosen algal density (0.5x10E6 and 1.5x10E6 cells/ml). Into each of the 30 test jars (five toxicant levels x two food levels x three replicates), we introduced 20 neonates (<3 hr following hatching). 25 degrees C, under continuous but diffused fluorescent illumination, pH 7.5.
Measurements/observation
Number of neonates born and dead adults.
Evaluations
Survivorship (average lifespan, life expectancy at birth) and reproductive (gross and net reproductive rates, generation time and rate of population growth).
[ref. ID; 6108]
Test system
The effect of UV-B radiation on acute toxicity (24-hr), reproduction test (2-day) and ingestion test (24-hr)
Strains
The strain used was originally collected in Gainesville, FL, in 1983, neonate females (4-6 hr old) hatched from cysts.
Toxicants
Pentachlorophenate sodium salt (PCP: 0, 20, 50, 100, 300, and 500 ug l-1), mercuric chloride (Hg: 0, 40, 50, 60, 70, and 80 ug l-1).
Test design
UV-B radiation was provided by an ultraviolet light. The UV-B source was maintained at a fixed distance of 25 cm from the test animals.
- Acute toxicity: Test animals were exposed to UV light (290-330 nm at half peak height) as the sole light source by placing 100 neonate animals in 2 ml of synthetic freshwater in a 60x15 mm polystrene petri dish (water depth 1 mm). UV-B exposure treatment (0, 10, 20, 30, 40, 50 or 60 min = peak UV-B doses (312 nm) of 0, 66, 132, 198, 264, 330 and 396 J m-2). Following UV-B exposures, 10 animals were transferred to a 24-well plate, where they were incubated in 500 ul of toxicant solution in darkenss for 24 hr at 25 degrees C. Six replicates were performed per UV-B exposure and toxicant concentration.
- Reproduction test: Procedure by Snell and Moffat (1992). Test animals were exposed to UV-B with exposure times of 0, 5, 10, 12.5, 15, and 20 min. Following UV-B exposures, six animals were placed in a 16x150 mm disposable glass test tube containing 12 ml of a 2.0x10E6 cells ml-1 suspension of Nannochloris oculata. Five replicate tubes were used per UV-B exposure. After the addition of animals, tubes were placed on a culture rotator (10-15 rph) and incubated for 48 hr in darkness at 25 degrees C.
- Ingestion test: Procedure by Juchelka and Snell (1994). Experiments consisted of a control and six UV-B exposures: 10, 20, 30, 40, 50, and 60 min. After UV-B exposure, animals were transferred to 750 ul of synthetic freshwater in 24-well plates with 10 animals per well and 4-6 replicate wells per UV-B treatment. This design was duplicated in sets of plates. One set was inculated for 24 hr in darkness at 25 degrees C in the absence of food, after which rotifer ingestion was assessed. The other set was used to assess rotifer ingestion rate immediately following UV-B exposure. For this set, 10 ul of a solution of 5-um diameter red polystyrene microspheres was placed in each well, yielding a final microsphere concentration of approximately 250,000 ml-1. The plates were then incubated in darkness at 25 degrees C for 15 min. After which, animals were anesthetized with 10.1 mM tricaine methane sulfonate, and a dissecting scope was used to count the number of animals per well which had ingested microspheres.
Measurements
- Acute toxicity: Number of dead animals.
- Reproduction test: Number of animals.
Evaluations
- Acute toxicty: LC50.
- Reproduction test: The intrinsic rate of increase (r).
[ref. ID; 6118]
Test system
24-hr acute, 48-hr asexual reproduction, and 96-hr resting egg toxicity
Strains
Originally collected in Gainesville, FL, in 1983. Test animals consisted of neonate females (4-6-hr-old) hatched from cysts.
Toxicants/concentrations
PCP sodium salt (10, 25, 50, 100, 200, and 400 ug/l), 4-nonylphenol, copper (0.8, 1.6, 2.8, 6, 12, 24, and 48 ug/l) sulfate, lead, mercury and testosterone.
Test design
96-hr resting egg toxicity test: 6 neonate females were exposed to toxicants in 16x150-mm disposable borosilicate glass test tubes containing 12 ml of hard synthetic freshwater (NaHCO3 96 mg, CaSO4/H20 60 mg, MgSO4 60 mg, and KCl 4 mg in 1L deionized water, pH 7.5) or toxicant solutions. Tubes were placed on a culture rotator (10-15 rph) and incubated for 96-hr in darkness at 25 degrees C. Five replicates (control, solvent control, and test compound). Food (Nannochloris oculata 3.0x10E6 cells/ml).
Measurements/obsevations
Number of sexual females carrying resting eggs, number of asexual and unfertilized sexual females, total number of resting eggs.
Evaluations
- LC50.
- EC50 using linear regression.
- NOECs, LOECs using pair-wise one-way analysis of variance (ANOVA) and Dunett's test.
[ref. ID; 7131]
Test system
Acute (24-hr) and chronic (48-hr) toxicity
Strains
Cysts were supplied by Micro Bio Tests.
Toxicants
Chloride.
Test design
- Acute toxicity: American Soceity for Testing Material (1991).
- Chronic toxicity: American Public Health Association Standard Method (2005).
B. calyciflorus were exposed in a culture plate using a 0.5-ml exposure volume and eight replicates per concentration, each containing one rotifer. The test was initiated with organisms that were <4-hr posthatch, and the solutions were supplemented with Pseudokirchneriella as food at test initiation. Exposures were conducted at 25 degrees C in the dark.
Measurements/observations
- Acute toxicity: Mortality.
- Chronic toxicity: Reproduction.
Evaluations
- Acute toxicity: LC50.
- Chronic toxicity: IC25, IC50.
[ref. ID; 779]
Test system
Sublethal toxicity tests (effect of food level)
Strains
Originally isolated from locally collected zooplankton and cultured successfully in the laboratory for over a year, amictic rotifers of 12+/-4 hr age.
Toxicants
DDT.
Test design/concentrations
Temperature 28+/-1 degrees C. pH 7.0. Chlorella strain ARC-3 (1 and 3x10E6 cell/L). 15 ml glass vials, 2 food levels x 5 DDT concentrations x 3 replicates. 48-hr LC50 tests were conducted at low and high food levels, first using wide, log-series range (0, 10, 100, and 1000 ug/l) and later a narrower range of 0-100 ug/l). Based on these preliminary tests, DDT levels of 15, 30, 45 and 60 ug/l were chosen for the final study.
Measurements/observations
Number of attached eggs, offspring and mortality.
Evaluations
LC50 and EC50 (survivorship (lx), life expectancy (ex), fertility (mx), net reproductive rate (Ro), generation time (T), intrinsic rate of natural increase (r), reproductive value (Vx), residual reproductive value (Vx*).
[ref. ID; 3303]
Test system
Sublethal effect
Strains
Isolated from a local waterbody.
Toxicants
2,4-Dichlorophenoxyacetic acid.
Test design/concentrations
36 transparent test jars (50 ml capacity): EPA medium (NaHCO3 96 mg/l, CaSO4 60 mg/l, MgSO4 60 mg/l, KCl 4mg/l), pH 7.4-7.6, continuous illumination, food (Chlorella vulgaris). 6 concentrations (0, 100, 200, 300, 400 and 500 mg/l) x 2 food levels (0.5x10E6 and 1.5x10E6 cells/ml) x 3 replicates. Temperature 23+/-1 degrees C.
Measurements/observations
Population growth rate, maximum population density.
Evaluations
Two-way analysis of variance on maximum populations density and the rate of population growth (toxicants concentration & food density).
[ref. ID; 3314]
Test system
24-hr acute toxicity assay and 20-days sublethal toxicity
Strains
From a local pond, neonate.
Toxicants
Methyl parathion.
Test design/concentrations
EPA medium (NaHCO3 96 mg/l, CaSO4 60 mg/l, MgSO4 60 mg/l, KCl 4mg/l), initial pH 7.2, continuous illumination, food (Chlorella vulgaris). Temperature 25 degrees C.
- LC50 test: 36 test jars (50 ml volume of medium in 100 ml containers), 5 concentrations (0, 2.5, 5.0, 10.0, 20.0, and 40.0 mg/l) x 2 food levels (1.5 and 3.0x10E6 cells/ml) x 3 replicates.
- Sublethal toxicity; 128 transparent jars (20 ml volume of medium in 50 ml containers), 7 concentrations (0, 0.16, 0.31, 0.62, 1.25, 2.5, 5.0, and 10.0 mg/l) x 4 food levels (0.75, 1.5, 3.0, and 6.0x10E6 cells/ml) x 4 replicates.
Measurements/observations
Mortality, population growth.
Evaluations
LC50, maximum populations density and population growth rate (r).
[ref. ID; 6771]
Test system
24-days sublethal toxicity
Strains
Originally isolated from the Ramsar Site Chimaliapan lake (Toluca City, Mexico).
Toxicants/concentrations
CuSO4 (Cu2+: 2.5, 5.0, 10 and 20 ug/L), HgCl2 (Hg2+: 0.675, 1.35, 2.7 and 5.4 ug/L).
Test design
Population growth experiments: 40 mL transparent jars, with 20 mL EPA medium (96 mg NaHCO3, 60 mg CaSO4, 60 mg MgSO4, and 4 mg KCl in 1 L of distilled water). 2 heavy metals x 4 concentrations x 4 replicates + 4 controls.
The initial density of rotifers was 1 ind./mL. Chlorella vulgaris (strain CL-V-3, CISESE, Ensenada, Mexico) at a density of 1.0x10E6 cells/mL offered daily in the test jars. Continuous diffused fluorescent illumination, pH 7.0-7.5 and temperature 24+/-1 degrees C. Experiment period 24 days.
Measurements/observations
Rotifer density, morphometoric study (lorica size, length of posterior and postero-median and anterior spines).
Evaluations
One way-analysis of variance on the population growth rate, body size (width) and postero-lateral spine length.
B. plicatilis is a euryhaline species which tolerates salinities from 1 up to 96 0/00. (Worley 1928; Ito 1960; Walker 1981). (ref. ID; 713)
[ref. ID; 128]
Test system
24-hr acute lethal toxicity
Strains
Cysts.
Toxicants
Fenitrothion, Chlorpyrifos, 3,4-Dichloroaniline (3,4-DCA), Trichlorfon, Lindane.
Test design/concentrations
Temperature 25 degrees C. 24-well polystyrene tissue plate (synthetic seawater (by mixing Instant Ocean salts with deionized water), salinity 15 ppt, pH 7.7), darkness, no food x six concentrations (including control) for one acute toxicity test x 3 replicates.
Measurements/observations
Survival data.
Evaluations
LC50 calculated using "moving-average" analysis.
[ref. ID; 156]
Test system
The effect of nutritional state upon a common sub-lethal toxicity marker, levels of the 60 kDa heat shock protein (hsp60)
Strains
From Southern California Edison (Long Beach, CA).
Toxicants
Crude oil (A), dispersed oil (DO), water-accommodated fraction (WAF).
Test design
Crude oil exposure media (EM) 4.0g PBCO (Prudhoe Bay crude oil) with or without 40 ul Corexit 9527 (the chemical dispersing agent; 48% nonionic surfactants: ethoxylated sorbitan monooleate, ethoxylated sorbitan trioleate, and sorbitan monooleate, 35% anionic surfactant: sodium dioctyl sulfosuccinate, 17% hydrocarbon solvent: ethylene glycol monobutyl ether) in 2.0 kg of 34 ppt seawater, with or without food (Isochrysis galbana).
Measurements/observations
hsp60.
[ref. ID; 713]
Test system
The effect of experimental conditions (salinity x temperature) for acute toxicity bioassays (24-hr LC50)
Strains
Originally collected from salinas near the Azov Sea.
Toxicants
K2Cr2O7, Sodium laurylsulphate (SLS).
Test design
In glass Petri dishes (diameter, 40 mm; height, 10 mm) filled with 5 ml of the respective toxicant concentration. Five animals per one petri dishes. 4 duplicates. Darkness.
A 4x4 temperature-salinity factorial test was performed. 10-17-24-31 degrees C for temperature and 5-25-45-65 0/00 for salinity.
Measurements/observations
The number of dead rotifer, which death is defined as the absence of internal or external movement for 10 seconds.
Evaluations
LC50
[ref. ID; 718]
Test system
Acute toxicity bioassays (24-hr)
Strains
The Russian strain (Snell and Carrillo, 1984), originally collected from salinas near the Azov Sea region. Cysts was obtained from Dr. Patrick Sorgeloos of the State University of Ghent in 1980. Neonate females collection should be completed 3 hr after hatching begins.
Toxicants/concentrations
Sodium pentachlorophenate (NaPCP)/0.7, 1.0, 1.3, 1.8, and 2.4 mg/l, sodium dodecyl sulfate (SDS), malathion, free ammonia (NH3), copper sulfate (CuSO4/5H2O), and cadmium chloride (CdCl2).
Test design
Standard Methods for the Examination of Water and Wastewater (1985) and USEPA (1985). Standard environmental condition: temperature 25 degrees C, salinity 15 or 30 ppt, pH 7.7, and darkness. In sterile, 24-well polystyrene tissue culture plates (Falcon 3047). One ml of test solution is placed in to each well and 10 neonate rotifers introduced. This density of 10 animals/ml gives a loading factor of 2 ug ml-1 since each neonate weighs approximately 0.2 ug. 4 replicates for each concentration.
Measurements/observations
Rotifer death is defined as the absence of internal or external movement for 10 seconds.
Evaluations
LC50 and NOEC.
[ref. ID; 1321]
Test system
1-hr esterase inhibition test
Strains
Russian strain, neonate.
Toxicants
Sodium Pentachlorophenate, Sodium dodecyl sulfate, Paraoxon, tributyl tin, Copper (atomic absorption standards), Mercury (atomic absorption standards), Zinc (atomic absorption standards), Calcium hypochlorite.
Test design
Fluorescein diacetate (FDA) was used to measure esterase activity. ASPM medium (NaCl 11.31 g/l, KCl 0.36 g/l, CaCl2 0.54 g/l, MgCl2/6H2O 1.97 g/l, MgSO4/7H2O 2.39 g/l, NaHCO3 0.17g/l: salinity 15 ppt: pH 8.0). Temperature 25 degrees C.
Measurements/observations
FDA-metabolizing enzymes, fluorescence at 515 nm.
Evaluations
NOEC, IC20.
[ref. ID; 1668]
Test system
Narcotic efficacy
Strains
'Russian strain' obtained from Dr T.W. Snell. Food: Selenastrum minutum (Dr D. Turpin).
Drugs
Benactyzine, Bupivacaine, Chloral hydrate, Chloretone, Decamethonium, EDTA, Hydroxylamine, K-oxalate, Lidocaine, Procaine, Propranolol, and Tricaine.
Test design
One ml drug solution was placed in the depression of Labtek tissue culture plates, and one ml rotifer suspension containing 100-200 individuals (concentrated by filtration) was added. The age and size of experimental animals used was not controlled.
Measurments/observations
Number of extended (corona above the edge of the lorica) animals and contracted animals.
Evaluations
EC50 (effective molar concentration causing narcosis in 50% of test animals), and rate of anesthesia (time necessary to cause narcosis in 50% of test animals).
[ref. ID; 6840]
Test system
Effect of copper-preaccumulating microalgae (food) for rotifer
Strains
From salt ponds near Cadiz (southeast of Spain).
Toxicants
Copper sulfate (CuSO4/5H2O).
Test design
Four microalgal species (Chlorella autotrophyca, Nannochloropsis gaditana clon B-3, Tetraselmis chuii, and Isochrysis aff. galbana clon T-Iso. All were obtained from the Marine Microalgal Culture Collection at the Instituto de Ciencias Marinas de Andalucia). An original amount of organic carbon as measurement of microalgal biomass of 2.5 pg C ml-1 was chosen for starting the accumulation experiment. 24 hr exposure to the metal (concentration 1 mg L-1).
Ten neonate rotifers were added to two series of three wells for each microalgal species (one species with preaccumulating microalgae, the other series with non-exposed microalgae). During the experiments organisms were cultured at 20+/-1 degrees C under continuous white light, in polystyrene 24-well plates, 1-ml capacity.
Measurments/observations
Number of rotifers.
[ref. ID; 7063]
Test system
Interstitial water toxicity
Strains
S-1 clone isolated from saltmarshes near Cadiz. Food: Nannochloropsis gaditana.
Toxicants
The sediment was collected using a Van Veen grab from the discharge point of highly contaminated urban effluent produced from San Fernando, an industrial town in SW Spain with approximately 100000 inhabitants. Interstitial water was extracted by centrifugation at 2600x g for two hours at 2 degrees C.
Test design
Experimental condition was a constant temperature of 25 degrees C and continuous light 2000 lux.
- Two control assays: The first one consisting of filtered seawater (C) and the second one of filtered seawater containing a mixed antibiotic solution (neomycin, amoxicillin and chloramphenicol in ratio 1:1:1 v/v), with a final mixture concentration of 21 mg/1 (C*). Oceanic water was collected (36 degrees 15'N 6 degrees 20'W), and then filtered (0.45 um).
- Two raw interstitial water assays: The first one consisting of interstitial water (IW) and the second one of the same water containing the mixed antibiotic solution as specified above (IW*).
- Two filtered interstitial water assays: The first one consisting of interstitial water filtered (0.45 um) (FIW), and the second one of the same water containing the mixed antibiotic solution as specified above (FIW*).
In all the assays, the rotifers were unfed and the medium was not renewed during the six days of the exposure time. The initial rotifer concentration was about 270 individual per ml for each duplicate of test mediums (50 ml). The length of rotifers ranged from 180-200 um. and the eggs:female ratio was 0.38.
Measurments/observations
Subsamples (0.5 ml) were taken daily (at least twice per day) for 6 days and counted (dead, total number of rotifer and amictic eggs). Number of heterotrophic bacteria.
Evaluations
Index of viability of the rotifer population.
- Time required for 50% of the population to die (TL50). TL50 was calculated by linear regression of log toxicant time on decline probit values, using a probit analysis modified from the classic methodology to obtain the common toxicological parameter: EC50 or LC50.
- The decline rate of B. plicatilis population. This was calculated as the slope of the straight line resulting from exponential regression of the rotifer density against time (hours).
- The area under the egg:female ratio curve against time. This was calculated by Simpson's rule.
[ref. ID; 7087]
Test system
The effects of salinity, pH, and dissolved organic matter on acute toxicity
Strains
Newly hatched B. plicatilis (<4 hr old). Rotifer cysts obtained from Florida Aqua Farms Inc., Dage City, FL, USA.
Toxicants
Copper standard (100 ug Cu/ml in 2% HNO3).
Test design
Static acute toxicity tests (48 hr, unfed) were performed using modified methods of those recommended by the ASTM (2004).
- Salinity effects: 6, 11, 13, 15, 20, 24, and 29 g/L. The saltwater was reconstituted by adding the synthetic sea salt Instant Ocean (Aquarium Systems, Mentor, OH, USA) to steamed-distilled water.
4 relicates of 10 rotifers per each concentration. 2 ml of test solution in 3.25-ml high-grade polystyrene vessels. Temperature 25+/-1 degrees C, continuous darkness.
- pH and dissolved organic carbon (DOC) effects: Natural saltwater from Little Egg Harbor, Tuckerton, NJ, USA.
- 7 g/L salinity exposure pH 6.8 and DOC 4.1 mg C/L, pH 8.3 (using 1 M NaOH) and DOC 4.0 mg C/L.
- 13 g/L salinity exposure pH 7.6 and DOC 1.7 mg C/L, pH 8.6 (using 1 M NaOH) and DOC 1.7 mg C/L.
Measurments/observations
Mortality.
Evaluations
LC50.
[ref. ID; 7819]
Test system
Acute and chronic toxicity
Strains
"L" strain obtained as cysts from Florida Aqua Farms Inc. (Dade City, FL, USA).
Toxicants
Copper.
Test design
Modified methods of those recommended by the ASTM (2004). 15 g/L salinity, at 25 degrees C, continuous darkness.
- Acute toxicity test: Two 48-h rstatic-acute toxicity tests - one with and one without added food (DT's Live Marine Phytoplankton-Premium Reef Blend). DT's Live Marine Phytoplankton-Premium Reef Blend (DT's Plankton Farm, Sycamore, IL, USA) contains live green algae Nannochloropsis oculata, Chlorella sp., and diatom Phaeodactylum tricornutum with cell diameters ranging from 2 to 20 um.
- Chronic toxicity: 96-hr static multigeneration life-cycle test (P1-F2 generations).
Measurments/observations
- Acute toxicity test: Mortality. Individual rotifers were scored as dead if there was no movement of body or parts (e.g. mastax) within 5 s of initiating an observation under stereoscopic microscope.
- Chronic toxicity: Number of live rotifers.
Evaluations
- Acute toxicity test: 48-hr LC50(Fed), 48-hr LC50(Unfed).
- Chronic toxicity: 96-hr NOEC, 96-hr LOEC, EC25, EC20, and EC10 based on the intrinsic rate of rotifer population increase (r).
- ACR(acute-to-chronic ratio) were calculated as ratios of each 48-hr LC50 value [fed and unfed) and each of the 96-hr chronic values (ChV; geometric mean of NOEC and LOEC)], EC10, EC20, and EC25.
[ref. ID; 818]
There are several advantages in using this species as a test organism:
- 1. They are cosmopolitan and common in mesotrophic and eutrophic ponds and lakes.
- 2. They are small (about 300 um length) and are easy to rear in a laboratory with sterile handling conditions.
- 3. They reproduce quickly and have a short generation time.
- 4. Because they are predominantly parthenogenetic, they can be cloned in order to obtain pure genetic lines for experimental studies.
- 5. The constancy of cell numbers per individual, a consequence of deterministic development and the lack of mitoses after the embryological period, results in an extremely constant life history, thus making these organisms appropriate for mathematical description.
- 6. The sexually produced resting eggs (diapause eggs) can be preserved by drying or storage in a refrigerator; they can be sent by mail, and hatching can be induced by simple manipulations (using water of low osmolarity and increasing temperatures up to 25 degrees C).
Test system
24-hr acute toxicity test & sublethal toxicity test
Strains
Brachionus rubens Ehrenberg isolated from pond N12 at the Nidda area near Frankfurt/Main, West Germany.
Toxicants
Phenol, Pentachlorophenol (PCP), 4-Chloroaniline, 4-Nitrophenol.
Test design
Temperature 25+/-1 degrees C. Medium (synthetic freshwater: CaCl2/2H2O 120 mg, NaH2PO4/H2O 50 mg, Na2HPO4/2H2O 100 mg, CaSO4/2H2O 60 mg, MgSO4/7H2O 60 mg, KNO3 100 mg, K2HPO4/3H2O 50 mg, in deionized water 1000 ml, traces of sodium silicate are added), food (Monoraphidium minutum (Nageli) Komarkova-Legnerova (20-70x10E6 cell/ml)).
Measurements/observations
Survival, numbers of eggs and offspring.
Evaluations
LC50 and EC50 (intrinsic rate of natural increase (r), carrying capacity (k), frequency (f), pregnancy (p)).
[ref. ID; 820]
Test system
24-hr acute toxicity test
Strains
Originally obtained from the algal culture unit maintained by Dr. Edward Lincoln at the University of Florida in Gainesville.
Toxicants
Copper sulfate, Sodium pentachlorophenate, Cadmium chloride, Sodium dodecyl sulfate, free ammonia, malathion.
Test design
24-well polystyrene plates. EPA medium (NaHCO3 96 mg/l, CaSO4/2H2O 60 mg/l, MgSO4 60 mg/l, KCl 4mg/l, pH 7.4-7.8, hardness 80-100 mg CaCO3/l, alkalinity 60-70 mg/l). Darkness. Temperature 25 degrees C.
Measurements/observations
Survival.
Evaluations
LC50, NOEC.
[ref. ID; 954]
Test system
Population dynamics of rotifers and its concequence for ecotoxicology
Strains
Strain (N12/III) from the Nidda-pond N 12 near Frankfurt in August 1979.
Toxicants/concentrations
Pentachlorophenol (PCP) 0, 0.05, 0.1, 0.15, 0.2, and 0.3 mg l-1: Phenol 0, 3, 5, and 10 mg l-1: 4-chloroanilin 10, 20, 40, and 80 mg l-1.
Measurements/observations
Number of animals
Evaluations
Carring capacity (K).
[ref. ID; 6099]
Test system
Chronic toxicity and the effect of CNP-accumulated Chlorella sp.
Toxicants
CNP.
Test design
- Chronic toxicity: ASW medium (3 ml) + food (Chlorella sp. 1x 0E7 cells/ml) + CNP (0, 10, 20, 40, 70 and 100 ug/l), 22+/-1 degrees, 12L-12D fluorescent light, 12 replicates.
- Effect of CNP-accumulated Chlorella: Chlorella was suspended in 2 liters of ASW were exposed to CNP at 0.2, 0.5, 1, 1.5 or 2 mg/l for 24 hr in a room at 23 degrees C and 12L-12D. 12 replicates.
Measurements
Number of offspring.