N-(1,4-dimethylpentyl)-N'-phenylbenzene-1,4-diamine

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study meets generally accepted scientific principles Lack of analytical monitoring data. Effect values should not be considered for risk evaluation.

Qualifier:

according to guideline

Guideline:

other: EPA-660/3-75-009

Deviations:

no

Principles of method if other than guideline:

EPA Methods for Acute Toxicity Tests with Fish, Macroinvertebrates and Amphibians. Environmental Protection Agency, Ecological Research Series
EPA-660/3-75-009, April, 1975. 61 p.
American Public Health Association. 1975. Standard Methods for the Examination of Water and Wastewater. 14th ed. Washington, DC. 1193 p.

GLP compliance:

yes

Analytical monitoring:

no

Details on sampling:

Test concentrations were prepared based on total compound. Nanograde acetone was used in the preparation of all working stock solutions. The solvent control received an aliquot 0.01 mL. of acetone equivalent to that of the highest test concentration.

Vehicle:

yes

Details on test solutions:

Aceton

Test organisms (species):

Daphnia magna

Details on test organisms:

Daphnia magna cultured at the ABC facilities.
Feeding with algae (Selenastrum capricornutum)
The daphnids were identified to species using the taxonomic key presented by Pennak.

Test type:

static

Water media type:

freshwater

Total exposure duration:

48 h

Hardness:

255 mg CaCO3

Test temperature:

21 °C

pH:

6.9 - 7.8

Dissolved oxygen:

6.6 - 7.4

Nominal and measured concentrations:

nominal conc.: 0.1, 0.18, 0.32, 0.56 and 1.0 mg/L

Details on test conditions:

An initial range finding experiment was conducted using 5 Daphnia each in exposure concentrations of .01, 0.1, 1.0 mg/L. From this infor mation, five concentrations in duplicate of the test compound with ten Daphnia (first instar less than 24 hours old) per beaker were selected for their respective bioassay. These concentrations were a logarithmic series ranging from 0.10 to 1.0 mg/L and included a control and solvent control. All concentrations were observed once every 24 hours for mortality and abnormal effects such as surfacing, clumping of the daphnia together and daphnids lying on the bottom of test chambers.

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

0.2 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: 0.10 -0.32 mg/L

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

0.1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Description of key information

The acute toxicity of 7PPD to Daphnia magna was investigated in a static test according to EPA-660/3-75-009. After 48 hours of exposure an EC50 of 0.2 mg/L (nominal) was determined.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

0.2 mg/L

Additional information

Short-term tests have been performed with 7PPD as well as with other similar PPDs yielding EC50-values in the range of 0.2 to 1.7 mg/L. The result of the study performed with 4-HDPA (0.69 mg/L) is within this range.  N-(1,4 -dimethylpentyl)-N'-phenylbenzene-1,4 -diamine (7PPD) is hydrolytically unstable at pH 7 and p-Hydroquinone CAS 123 -31 -9 was identified as the most sensitive (secondary) hydrolysis product. The lowest effect value in acute tests was found for p-Hydroquinone (0.134 mg/L) which is close to the values for the PPDs (0.2 to 1.9 mg/L) and 4-HDPA (0.69 mg/L). p-Hydroquinone is a secondary hydrolysis product of 7PPD, athough having the lowest effect concentration this value was not chosen as key value as the hydrolysis from 7PPD to p-Hydroquinone is rather slow.