Slimes and Sludges, zinc sulfate electrolytic

Long-term toxicity to fish

Administrative data

Endpoint:

fish early-life stage toxicity

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

No guideline followed. Study well conducted and documented. All NOEC values in the paper seem un-bounded (NOEC< lowest reported values). The NOEC for survival and abnormalities reported in this IUCLID-file were obtained by probit analysis using the raw data as given in the original publication (P<0.02).

Cross-reference

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

1994

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

long term toxicity testing of lead to fish

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Lead dinitrate

EC Number:

233-245-9

EC Name:

Lead dinitrate

Cas Number:

10099-74-8

Details on test material:

no details provided

Sampling and analysis

Analytical monitoring:

yes

Test solutions

Vehicle:

no

Test organisms

Test organisms (species):

Cyprinus carpio

Details on test organisms:

TEST ORGANISM
- Common name: common carp


METHOD FOR PREPARATION AND COLLECTION OF FERTILIZED EGGS
Artificial fertilization of carp eggs as described by Oyen et al. (1991)
- Numbers of parental fish (i.e. of females used to provide required number of eggs): three different males
- Method of collection of fertilised eggs: carp eggs (300-400) placed in petridishes were fertilized by sperm from three different males, resulting in three different batches of eggs.
- Subsequent handling of eggs: Immediately after fertilization different petridishes with the fertilized eggs stuck to the bottom were placed in a 4L aquarium (five per group; for details see Oyen et al., 1991; Oyen, 1993)

Study design

Test type:

flow-through

Water media type:

freshwater

Limit test:

no

Total exposure duration:

7 d

Test conditions

Hardness:

35 mg/L CaCO3

Test temperature:

23°C

pH:

5.6 ± 0.07 (control)

Nominal and measured concentrations:

nominal concentrations:0.12;0.24;0.48;0.96 µmol/L (= 24.9;49.7;99.5;198.9 µg/L)
Measured concentrations: Desired Pb concentrations were within 5% of the calculated values as verified by Atom Absorption Spectrophotometric (AAS) analyses.

Details on test conditions:

TEST SYSTEM
- Embryo cups (if used, type/material, size, fill volume): petri-dish
- Test vessel:
- Material, size, headspace, fill volume: 4L aquarium
- Type of flow-through (e.g. peristaltic or proportional diluter):
- Renewal rate of test solution (frequency/flow rate): complete turnover in 10h
- No. of fertilized eggs/embryos per vessel:5
- No. of vessels per concentration (replicates):6


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water:artificial water: demineralized water containing the following ions(in mmol/L):
0.06 KCl; 0.4 NaHCO3; 0.2 MgSO4; 0.8 CaCl2

OTHER TEST CONDITIONS
- Adjustment of pH: Water pH was adjusted to 5.6 via gradual addition of 0.01M sulfuric acid using pH-stat equipment
- Photoperiod: 12h light

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : Mortality of eggs and larvae, deformation of larvae were examined.
Dead eggs and larvae were counted at 6, 12, 25, 48, 72, 96, 120, 144 and 170h after fertilization and immediately removed to prevent fungal growth. Eggs were considered dead when parts of the content turned opaque and white, or when heart beat had stopped. The percentage of deformed larvae (including dead ones) was determined after microscopic examination.

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

7 d

Dose descriptor:

EC10

Effect conc.:

17.8 µg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

other: (estimated using the conversion equation according to Blust (2010); the actual measured total Pb EC10 is 17.8 (3.6-86.6) ug/L)

Basis for effect:

mortality

Remarks on result:

other: confidence limits: 3.6-86.6 µg/L

Effect concentrations 2

Duration:

7 d

Dose descriptor:

EC10

Effect conc.:

48.8 µg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

other: (estimated using the conversion equation according to Blust (2010); the actual measured total Pb EC10 is 48.8 (30.1-79.0) ug/L)

Basis for effect:

morphology

Remarks:

abnormalities of larvae

Remarks on result:

other: confidence limits: 30.1-79.0 µg/L

Reported statistics and error estimates:

Data are expressed as means ±SE(n=6). A one-way analysis of variance was used to assess differences between groups. Significance of differences was subsequently tested using the Student t-test. Significance was accepted for P<0.05. Significance is expressed at the level of P<0.05; P<0.02;P<0.01;P<0.001 compared to control, values. EC10 values were calculated using log-logistic curve fitting of the raw data

Applicant's summary and conclusion

Executive summary:

Fertilized eggs of the carps were placed in 4L aquaria containing salts dissolved in demineralized water. Therefore a very low background Pb concentration ( 1µg/L) was assumed. Temperature was maintained at 23°C. The dilution factor was 0.5. Statistics was reported, but all NOEC values seemed to be unbounded (NOEC lowest reported values). However, from the raw data own probit analysis could be performed and the following reliable EC10 values at pH 5.6 could be calculated: 20 µg Pb/L for the endpoint survival and 49 µg Pb/L for the endpoint deformation.