Bis(4-methylbenzoyl)peroxide

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

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study was performed under GLP according to protocol. It was reviewed in the HPV program and recorded in the OECD SIDS dossier as reliability 1.

Qualifier:

according to guideline

Guideline:

OECD Guideline 211 (Daphnia magna Reproduction Test)

GLP compliance:

yes

Analytical monitoring:

yes

Vehicle:

no

Test organisms (species):

Daphnia magna

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

21 d

Nominal and measured concentrations:

Nominal: 0.1, 0.32, 1.0, 3.2 and 10 mg/L
TWA: 0.10, 0.32, 1.01, 3.23 and 10.2 mg/L

Reference substance (positive control):

not specified

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

3.2 mg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

test mat.

Basis for effect:

reproduction

Conclusions:

This study is reliable. It is performed according to OECD guideline 211 under GLP it was reviewed during the HPV process. The calculated endpoints are adequate for C&L and risk assessment purposes.

Executive summary:

A chronic toxicity of p-toluic acid to daphnids (Daphnia magna) on reproduction was reported (MOE, Japan. 2003). A semi-static test (renewed test solution every 24 or 48 hours) was conducted at nominal concentrations ranging 0.1, 0.32, 1.0, 3.2 and 10 mg/L of the chemical in geometrical series with a separating factor of 3.2 together with a blank control. The exposure concentrations, monitored analytically by using a HPLC, in each concentration did not change significantly, ranging 99.9 - 102.7 % of nominal at the initial and after renewal, and ranging 95.0 - 102.7 % of nominal at before renewal, respectively. However the measured concentration showed p-toluic acid should be stable under test condition; the toxicity was calculated based on mean measured concentrations (Time Weighted Mean; OECD TG-211), these were 0.10, 0.32, 1.01, 3.23 and 10.2 mg/L, respectively, very close to the nominal values. At the highest concentration of 10.2 mg/L (mean measured concentration) one of ten parent individual died on the 14th day. No more mortality was recorded in any other treatment group, but at the control 10 % (one of ten individuals) was dead. The time required to first brood in each treatment group was almost same with in control. There was no difference statistically among control and each treatment group on the mean cumulative number of offspring produced by a female except the highest concentration (inhibition rate on reproduction of 23 %). In the control one female produced 135 offspring in average of replicates. Then, the NOEC was estimated 3.2 mg/L on reproduction. The reliability of the test is high because there are no deviations from the OECD test guideline 211.

Description of key information

A chronic toxicity ofp-toluic acidto daphnids (Daphnia magna) on reproduction was reported (MOE, Japan. 2003). A semi-static test (renewed test solution every 24 or 48 hours) was conducted at nominal concentrations ranging 0.1, 0.32, 1.0, 3.2 and 10 mg/L of the chemical in geometrical series with a separating factor of 3.2 together with a blank control. The exposure concentrations, monitored analytically by using a HPLC, in each concentration did not change significantly, ranging 99.9 - 102.7 % of nominal at the initial and after renewal, and ranging 95.0 - 102.7 % of nominal at before renewal, respectively. However the measured concentration showedp-toluic acidshould be stable under test condition; the toxicity was calculated based on mean measured concentrations (Time Weighted Mean; OECD TG-211), these were 0.10, 0.32, 1.01, 3.23 and 10.2 mg/L, respectively, very close to the nominal values.At the highest concentration of 10.2 mg/L (mean measured concentration) one of ten parent individual died on the 14th day. No more mortality was recorded in any other treatment group, but at the control 10 % (one of ten individuals) was dead. The time required to first brood in each treatment group was almost same with in control. There was no difference statistically among control and each treatment group on the mean cumulative number of offspring produced by a female except the highest concentration (inhibition rate on reproduction of 23 %). In the control one female produced 135 offspring in average of replicates. Then, the NOEC was estimated 3.2 mg/L on reproduction.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

3.2 mg/L

Additional information

Due to rapid hydrolysis of 895-85-2 (see van Dam, 2014), the aquatic results of p-toluic acid are considered most relevant.