2-methyl-p-phenylenediamine sulfate

Exposure related observations in humans: other data

Administrative data

Endpoint:

exposure-related observations in humans: other data

Type of information:

experimental study

Adequacy of study:

key study

Study period:

no data

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Well-documented study report which meets basic scientific principles.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Materials and methods

Type of study / information:

Type of method: In-vivo
Objetive of study: To evaluate the genetic toxicity (chromosomal aberration) of formulations containing p-(Me14C) Toluenediamine after treatment in humans.

Endpoint addressed:

genetic toxicity

Test guideline

Qualifier:

no guideline available

Principles of method if other than guideline:

The human subjects were treated with formulations and the chromosomal aberrations were evaluated in blood (lymphocytes) samples before and after treatment.

GLP compliance:

no

Remarks:

For human Clinical trial, GLP is not applicable.

Test material

Test material information

Constituent 1

Reference substance name:

2-methyl-p-phenylenediamine

EC Number:

202-442-1

EC Name:

2-methyl-p-phenylenediamine

Cas Number:

95-70-5

Molecular formula:

C7H10N2

IUPAC Name:

2-methylbenzene-1,4-diamine

Constituent 2

Reference substance name:

p-toluenediamine

IUPAC Name:

p-toluenediamine

Details on test material:

- Name of test material (as cited in study report): p-toluenediamine
- Specific activity: 7.63 µCi/mg
- Locations of the label: The radiolabelling was located in the methyl group.

Method

Ethical approval:

confirmed and informed consent free of coercion received

Details on study design:

TEST SYSTEM
- Species: Human (healthy, adult)
- Sex: male
- Age at study initiation: 20 to 45 yrs.
- Weight at study initiation: 73.2 ± 4.35 kg
- Dose selection rationale: Studies in rats and preliminary studies in human were conducted and dose was selected accordingly.
- Preparation of test formulations: Formulations contained creamy substance containing resorcinol (88.35 g), cold solution of 2-methyl-p-phenylenediamine sulphate (1.6384 g) and radiolabelled test substance (0.0116 g). The above mixture was added in water (10 g, KOH, pH-9.4) to get 100 g mixture.
To prepare formulation I, 100 g of water was added to 100 g of above mixture.In case of preparation of formulation II, 100 g of hydrogen peroxide (6%) was added to 100 g of above mixture.
- Each of the two formulations was prepared immediately before treatment and each subject received of 45 g formulation (contained 371 mg of test substance and 19.98 µCi total radioactivity).
Further details are provided in the study report.

Exposure assessment:

measured

Details on exposure:

TYPE OF EXPOSURE: Dermal (applied to hair bearing scalp)
- Area of exposure: 250 cm2
- Amount applied: 45 g of formulation
- Dose concentrations: 371 mg/45 g formulation
- Vehicle used: Water (formulation I) and hydrogen peroxide (6%) (formulation II)
- Number of subjects/group: 5
- Control group: Baseline measurements values of treated subjects were used as control values.

EXPOSURE PERIOD: 30 min

REMOVAL OF TEST SUBSTANCE
- Washing: The test material was removed with shampoo washings.
- Time after start of exposure: 30 min (once)

SAMPLE COLLECTION
Sample collected: Blood
- Blood samples were collected from antecubital vein, before treatment (7 d) as baseline value and after treatment at Day 1, 3, 7 and 14.

POST EXPOSURE PERIOD: 14 d

DESCRIPTION OF EXPOSURE GROUPS: Group I and II, of 5 individuals each, were exposed to formulations I and II, respectively.

Results and discussion

Results:

RESULTS OF CHROMOSOMAL ABERRATION
- There were no changes in the incidence of chromatid gaps, deletions or exchanges were observed in any of the post-application samples compared with pre-dosing baseline values.
- Chromosome aberrations such as dicentric, iso-locus deletion and exchanges were scored, but the incidence of such aberrations was not significantly increased between pre-application and post- application samples. Thus these data did not suggest any chromosomal aberration of lymphocyte after treatment with formulations.
- The details of individual values of chromosomal aberrations are reported in study report.
- The mean (%) results of chromatid and chromosome aberrations are reported in ‘Table 1’ and ‘Table 2’ under ‘Any other information on results incl. tables’

Any other information on results incl. tables

Table 1: Mean chromatid aberration (%) values after treatment with formulations containing p (Me14C) toluenediamine of lymphocytes for 300 metaphases of each sample (study # 79249)

Groups

Baseline values (%)(±SEM)

Post treatment values (%) (±SEM)

Day 1

Day 3

Day 7

Day 14

G

D

E

G

D

E

G

D

E

G

D

E

G

D

E

Formulation I

0.66± 0.29

0.06± 0.06

0

0.66 ±0.66

0.13 ±0.13

0

0.53± 0.53

0.13± 0.13

0

0.53± 0.27

0

0

0.59± 0.32

0.13± 0.08

0

Formulation II

0.66± 0.23

0.06 ±0.06

0

0.66± 0.23

0.06± 0.06

0

0.53± 0.22

0.06 ±0.06

0

0.39 ±0.16

0.06 ±0.06

0

0.53± 0.27

0.06 ±0.06

0

G = gaps, D = deletions, E = exchange 

Table 2: Mean chromosomal aberration (%) values after treatment with formulations containing p-(Me14C) toluenediamine of lymphocytes for 300 metaphases of each sample (study # 79249)

Groups	Baseline mean % aberrations (±SEM)	Post treatment mean % aberrations (±SEM)
		Day 1	Day 3	Day 7	Day 14
Formulation I	0.13 ±0.08	0.06± 0.06	0.13 ±0.08	0.06 ±0.06	0.06 ±0.06
Formulation II	0.19 ±0.13	0.13 ±0.08	0.06 ±0.06	0.06± 0.06	0.06± 0.06

Applicant's summary and conclusion

Conclusions:

The formulations containing p-(Me-14C)-toluenediamine did not induce lymphocyte chromosomal aberrations after treatment to hair bearing scalp in healthy adult humans for 30 min.

Executive summary:

The purpose of the study was to investigate the induction of chromosome aberrations in lymphocytes following the topical application of two formulations containing p-(Me-14C)-toluenediamine to the hair-bearing scalp of adult healthy male subjects (5/formulation group).

The two formulations I and II were prepared with 50% of water and 50% of hydrogen peroxide (6%), respectively. The 45 g of formulations (contained 371 mg of test substance and 19.98 µCi total radioactivity) were applied to each individual to hair bearing scalp for 30 min.

The blood samples were collected at Day 7 before treatment (as baseline value) and Day 1, 3, 7 and 14 after treatment.

Blood samples (lymphocytes) were suspended in 0.5 mL of culture medium and incubated (37°C, 5% CO2) for 2 h. The samples were incubated with Colcemid (to arrest cell division in metaphase) (0.3µg/mL). The slides were prepared and the lymphocytes were fixed (methanol-acetic acid (3:1) solution for 30 min) and stained with giemsa (1:20 in water) at pH 7.2 for 6 min.

The slide were randomly coded and analyzed for 300 metaphases for each sample. The values are expressed as % of metaphase showing specific aberrations of chromatid gaps, deletions and exchanges.

There were no changes in the incidence of chromatid gaps, deletions or exchanges in any of the post-application samples compared with pre-dosing baseline values.

Chromosome aberrations such as dicentric, iso-locus deletion and exchanges were scored, but the incidence of such aberrations were not significantly increased between samples or by comparison with post-application samples with baseline pre-application values.

No chromosomal aberration of lymphocyte was observed after treatment with formulations.

The formulations containing p-(Me-14C)-toluenediamine did not induce lymphocyte chromosomal aberrations after treatment in healthy adult humans for 30 min, applied topically to hair bearing scalp.