5-chloro-2-(4-chlorophenoxy)phenol;[DCPP]

Long-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

other: Transformation product of Diclosan

Adequacy of study:

disregarded due to major methodological deficiencies

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

GLP Guideline study with deficiencies: Poor analytical recovery of the test item in the aged test solutions; high parental mortality at the selected test concentrations; according to OECD 211 “the range of test concentrations should preferably not include any concentrations that have a statistically significant effect on adult survival since this would change the nature of the test […].”; The effect concentrations are based on the initially measured concentrations of the new test solutions. Since the fate of the test item is not proven and effects were not only observed directly after addition of the test solutions, the effect values should be based on average concentrations (preferably time-weighted average). This is a methodological error. The time-weighted average concentrations have been recalculated for this robust study summary.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2003

Report date:

2003

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 211 (Daphnia magna Reproduction Test)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

4640-07-7

Cas Number:

4640-07-7

IUPAC Name:

4640-07-7

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Details on test material:

- Name of test material (as cited in study report): FAT 80'221/B (Methyldiclosan, degradation product of Diclosan)
- Molecular formula (if other than submission substance): C13H10O2CI2, 2-Methoxy-4,4'-dichlorodiphenylether
- Molecular weight (if other than submission substance): 245.1 g/mol
- Physical state: white powder
- Analytical purity: 99.7%
- Lot/batch No.: ETH-636/2A
- Expiration date of the lot/batch: expiration date: 31 July 2007
- Storage condition of test material: at room temperature, closed polyethylene vessel
- Other: Water solubility: 0.322 ± 0.018 mg/L; Homogeneous and stable, not volatile; Log Pow: 4.58 (estimated)

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 0 and 100 mg/L at test start and test end
- No data on sampling technique and sample storage

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: A super-saturated stock solution of the test item was prepared. This was done by mixing 100 mg/L of the test item with dilution water and shaking vigorously for 24 hours. The resulting solution was filtrated through 0.45 µm filters. The stock solution then was used to prepare the solutions of the concentrations to be tested.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: waterflea
- Strain/clone: Berlin
- Source: LAUS GmbH
- Age of parental stock (mean and range, SD): no data; method of breeding: Females multiplied by parthenogenesis; Holding: glass beakers (2 L), medium M4 (Elendt), feeding with, change of medium twice a week, photo period 16/8 h (fluorescent tubes), T = 21±2°C; feeding: Tetra Aminin® (cold-water fish food) suspended in M4 and boiled for three seconds; green algae Pseudokirchneriella subcapitata
- Feeding during test
- Food type: Unicellular green alga (Pseudokirchneriella subcapitata)
- Amount: 0.15 mg org. C/animal/day
- Frequency: 3 times per week

Study design

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

21 d

Test conditions

Test temperature:

- 19.7 to 20.7 °C (test concentrations with living daphnids at test end)
- 19.8 to 21.8 °C (test concentrations where all parental animals did not survive until test end)

pH:

Control: 6.5 to 8.0
Test concentrations: new: 6.0 to 7.3; aged: 6.7 to 8.4

Dissolved oxygen:

8.6 to 9.8 mg/L

Nominal and measured concentrations:

nominal (loading): 0, 625%, 12,5%, 25%, 50%, and 100% of super-saturated solutions
measured (TWA, µg/L): 0, 5.6, 12.3, 34.7, 56.1, 181.4

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Type (delete if not applicable): open
- Material, size, headspace, fill volume: glass beakers, 100 mL (nominal), 80 mL fill volume
- Aeration: Dilution water was aerated prior to preparation of test solutions. Test solutions were not aerated.
- Renewal rate of test solution (frequency/flow rate): Three times per week
- No. of organisms per vessel: 1
- No. of vessels per concentration (replicates): 10
- No. of vessels per control (replicates): 10
- Biomass loading rate: 80 mL/parent animal

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: M4-medium (Drinking water with an enrichment of minerals is used in the test (calcium chloride, magnesium sulphate, sodium chloride, potassium chloride).)

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: not specified (breeding and holding conditions: 16/8hours,usingneontubes
- Light intensity: ≤ 2000 Lux

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :

RANGE-FINDING STUDY
- Test concentrations:
- Results used to determine the conditions for the definitive study:

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

12.3 µg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

act. ingr.

Basis for effect:

reproduction

Effect concentrations 2

Duration:

21 d

Dose descriptor:

LOEC

Effect conc.:

34.7 µg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

act. ingr.

Basis for effect:

reproduction

Effect concentrations 3

Duration:

21 d

Dose descriptor:

EC50

Effect conc.:

> 34.7 µg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

act. ingr.

Basis for effect:

reproduction

Effect concentrations 4

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

< 5.6 µg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks:

adult mortality

Details on results:

The validity criteria for the control replicates were kept. Therefore the study is to be regarded as valid according to OECD 211. Nevertheless, the poor analytical recovery of the test item in the aged test solutions is critical. In addition the high parental mortality at the selected test concentrations should be regarded as a deficiency of this study. According to OECD 211 “the range of test concentrations should preferably not included any concentrations that have a statistically significant effect on adult survival since this would change the nature of the test […].”

Any other information on results incl. tables

Analytically determined test concentrations (TWA = time-weighted average)

Saturation (%)	Solution	Measured test item concentraion (µg/L) on day									Mean (µg/L)	TWA (µg/L)
		0	2	5	7	9	12	14	16	21
0	new	0.0	0.0	0.0	0.0	0.0	0.0	0.0	0.0	0.0	0.0	0
	aged	-	0.0	0.0	0.0	0.0	0.0	0.0	0.0	0.6	0.1
6.25	new	7.5	24.2	18.6	15.0	20.7	7.8	23.7	20.2	-	17.2	5.6
	aged	-	0.0	0.0	0.0	0.0	0.0	0.0	0.0	7.7	1.0
12.5	new	16.5	49.6	42.2	37.5	36.4	23.5	41.4	47.1	-	36.8	12.3
	aged	-	5.4	0.0	2.9	0.4	0.0	0.6	0.0	11.0	2.5
25	new	74.7	105.9	91.3	73.4	69.4	53.1	92.1	74.3	-	79.3	34.7
	aged	-	21.9	4.9	44.8	6.3	0.0	0.0	0.0	42.2	15.0
50	new	158.0	188.3	178.2	145.1	140.2	-	-	-	-	162.0	56.1
	aged	-	31.8	6.7	30.8	19.9	0.0	-	-	-	17.8
100	new	345.6	410.1	-	-	-	-	-	-	-	377.9	181.4
	aged	-	90.6	53.8	-	-	-	-	-	-	72.2

 

 

Fecundity (living offspring per parent animal alive at test termination)

Saturation%	control (0)	6.25	12.5	25	50	100
Parent animals alive at test end	9	7	6	4	0	0
Mortality	10%	30%	40%	60%	100%	100%
Mean	71	71	76	57	0	0
Min	60	46	55	47	0	0
Max	88	89	96	61	0	0
SD	8	15	16	7	-	-
CV	0.11	0.21	0.21	0.12	-	-
Fecundity (% of control)	-	99%	106%	80%	0%	0%

In the treatment 50%, all parent animals except for replicate 7 and 8 were found dead on day 5. In the treatment 100% all parent animals were found dead on day 4