4-aminophenol

Long-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

April 8 to May 15, 1997

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Test procedure in accordance with generally accepted scientific standards and described in sufficient detail

Qualifier:

according to guideline

Guideline:

other: OECD Guideline 202 (Daphnia acute immobilisation test and reproduction test 1984

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

see below

Vehicle:

no

Details on test solutions:

see below

Test organisms (species):

Daphnia magna

Details on test organisms:

see below

Test type:

flow-through

Water media type:

freshwater

Limit test:

no

Total exposure duration:

21 d

Hardness:

55.6 mg/L as CaCO3

Test temperature:

20+/- C

pH:

7.7

Nominal and measured concentrations:

Concentrations of PAP maintained between 82.5 an d 87.8 % depending on the nominal concentration.

Details on test conditions:

see below

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

0.206 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Remarks:

concentrations of PAP maintained between 82.5 an d 87.8 % depending on the nominal concentration

Basis for effect:

other: mean cumulative number of juveniles produced per adult

Remarks on result:

other: Values based on mean measured concentrations calculated directly from data in the study report.

Duration:

21 d

Dose descriptor:

EC50

Effect conc.:

> 0.171 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

immobilisation

Remarks on result:

other: 95% CL

Details on results:

Values based on mean measured concentrations calculated directly from data in the study report.

- Measured Concentrations: The test concentrations were measured 5 times (0, 4, 7, 14, 21st-day) using HPLC.

Nominal Conc. (mg/L)	Measured Concentration (mg/L)
	0	4	7	14	21
Control	---	---	---	---	---
0.0156	0.0134	0.0131	0.0138	0.0121	0.0135
0.0313	0.0263	0.027	0.028	0.0277	0.0273
0.0625	0.0539	0.0521	0.056	0.0566	0.0558
0.125	0.105	0.103	0.109	0.105	0.104
0.25	0.208	0.191	0.208	0.215	0.209

Nominal Conc. (mg/L)	Arithmetic Mean	% of Nominal
Control	--	--
0.0156	0.0132	84.6
0.0313	0.0273	87.1
0.0625	0.0549	87.8
0.125	0.105	84.2
0.25	0.206	82.5

- Water chemistry (pH, DO, total hardness and temperature in test): Water chemistry and temperature were measured for control and each concentration at 0, 4, 8, 12, 17 and 21st-day.
pH: 7.1 - 7.7
DO: 8.8 - 9.0 mg/L (more than 60% of saturation)
Water Temperature: 19.9 - 20.1 C

- Cumulative Number of Died Parental Daphnia:

Measured Conc. (mg/L)	Cumulative Number of dead parental Daphnia (Percent Mortality)
	0	4	7	14	21
Control	0 (0)	0 (0)	0 (0)	2 (5.0)	6 (15.0)
0.0132	0 (0)	0 (0)	0 (0)	0 (0)	6 (15.0)
0.0273	0 (0)	0 (0)	1 (2.5)	6 (15.0)	10 (25.0)
0.0549	0 (0)	0 (0)	0 (0)	0 (0)	8 (20.0)
0.105	0 (0)	0 (0)	7 (17.5)	11 (27.5)	14 (35.0)
0.206	0 (0)	1 (2.5)	20 (50.0)	22 (55.0)	25 (62.5)

-Time (days) to First Brood Production
Control: 7 days
Concentrations: 7 - 9 days

-Cumulative numbers of juveniles produced per adult alive

Nominal Conc. (mg/L)	Measured Conc. (mg/L)	Mean Cumulative Numbers of Juveniles Produced Per Adult Alive for 21 days
		Days
		0---6	7	8	9	10	11	12	13	14
Control	---	0---0	0.4	0.4	4.3	4.3	4.3	13.4	13.4	32.8
0.0156	0.0132	0---0	0.5	0.5	6.5	6.5	6.5	19.2	19.2	30.1
0.0313	0.0273	0---0	1.0	1.0	5.1	5.1	5.1	17	17	35.5
0.0625	0.0549	0---0	1.4	1.4	5.2	5.2	5.2	15.7	15.7	32
0.125	0.105	0---0	2.6	2.6	4.8	4.8	8.4	17.8	17.8	53
0.25	0.206	0---0	3.7	3.7	5.6	5.6	5.6	18.2	18.2	53.2

Nominal Conc. (mg/L)	Measured Conc. (mg/L)	Mean Cumulative Numbers of Juveniles Produced Per Adult Alive for 21 days
		Days
		15	16	17	18	19	20	21
Control	--	32.8	66.6	66.6	66.6	97.4	97.4	124
0.0156	0.0132	30.1	65.6	65.6	65.6	110	110	142
0.0313	0.0273	35.5	71	71	71	113	113	135
0.0625	0.0549	32	74	74	74	105	105	128
0.125	0.105	53	108	108	108	158	158	182
0.25	0.206	53.2	111	111	111	163	163	200

-Cumulative numbers of juveniles produced per adult alive for 21 days

Vessel No.	Measured Concentration* (mg/L)
	Control	0.0132	0.0273	0.0549	0.105	0.206
1	95	129	126	104	170	140
2	155	111	169	129	199	234
3	96	173	112	118	136	286
4	150	156	133	161	223	141
Mean	124	142	135	128	182	200
S.D.	32.7	27.5	24.6	24.4	37.5	72.2

*: Arithmetic mean of measured concentration

The average numbers of offspring in each treated groups were larger than that of control of 124 juveniles per female.
The significant parent mortalities were observed at 0.11 and 0.21 mg/L as 28 and 55%, respectively

Validity criteria fulfilled:

yes

Conclusions:

The EC50 at 21 days immobilization was 0.171 mg/L, the NOEC based on the mean cumulative number of juveniles produced per adult was 0.206 mg/l and the LOEC was > 0.206 mg/L.

Description of key information

The long-term to invertebrates key study reported a 21 day NOEC of 0.206 mg/L based on cumulative number of juveniles produced per adult.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

0.206 mg/L

Additional information

For long-term toxicity to invertebrates, one key experimental study in daphnia magna was reported. Daphnia Acute Immobilisation test and Reproduction test according to OECD 202 with a NOEC (21 d) of 0.206 mg/L based on cumulative number of juveniles produced per adult on freshwater invertebrates.Values based on mean measured concentrations calculated directly from data in the study report.