polymeric zinc propylenebis(dithiocarbamate);propineb (ISO)

Repeated dose toxicity: dermal

Administrative data

Endpoint:

short-term repeated dose toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1979

Report date:

1979

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 410 (Repeated Dose Dermal Toxicity: 21/28-Day Study)

GLP compliance:

no

Remarks:

Study was performed pre-GLP

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

polymeric zinc 1,2-propylenebis(dithiocarbamate)

EC Number:

620-365-5

Cas Number:

9016-72-2

IUPAC Name:

polymeric zinc 1,2-propylenebis(dithiocarbamate)

Test material form:

solid

Remarks:

Powder

Test animals

Species:

rabbit

Strain:

New Zealand White

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Weight at study initiation: 2.8-3.4 kg
- Housing: The rabbits were housed singly in standard type rabbit cages.
- Diet: Z 222 Pelleted Rabbit Breeding Diet
- Water: Water was provided ad libitum

ENVIRONMENTAL CONDITIONS
- Temperature: 21 ± 2°C
- Photoperiod: artificially lit daily from 7 a.m. to 7 p.m.

Administration / exposure

Type of coverage:

open

Vehicle:

other: Cremophor EL (approx. 1.5 % v/v) and distilled water

Details on exposure:

TEST SITE
- Test site preparation: The back and flanks of each rabbit were clipped free of hair 48 hours prior to initiation of test compound application. On 3 males and 3 females of each group, the skin areas to be treated were additionally abraded with sandpaper to induce reddening and slight to
moderate swelling of the skin, 24 hours prior to commencement of treatment.
- Area of exposure: Back and flanks of each rabbit, 5x5 cm
- Type of wrap if used: No wrap used.
- Time intervals for shavings or clippings: New growth of hair in and around the treated skin areas was removed once weekly with clippers.

REMOVAL OF TEST SUBSTANCE
- Washing: The treated skin areas were washed with soap and water
- Time after start of exposure: 7-hours

TEST MATERIAL
- Amount applied : 0.5 mL/kg bw

USE OF RESTRAINERS FOR PREVENTING INGESTION: yes

Analytical verification of doses or concentrations:

not specified

Duration of treatment / exposure:

7 hours per day for 15 days

Frequency of treatment:

The emulsion was applied once daily on 15 consecutive work days (5 applications per week)

Doses / concentrations

Doses / concentrations 1

Dose / conc.:

0 mg/kg bw/day

Remarks:

Control group

Doses / concentrations 2

Dose / conc.:

50 mg/kg bw/day

Remarks:

Low Dose Group

Doses / concentrations 3

Dose / conc.:

250 mg/kg bw/day

Remarks:

High Dose Group

No. of animals per sex per dose:

6 animals/sex/group

Control animals:

yes

Details on study design:

Prior to each application, LH 30/Z was emulsified in Cremophor EL (approx. 1.5 % v/v) and distilled water. The emulsion was applied once daily on 15 consecutive work days (5 applications per week) to the clipped skin areas on the back and flanks of each rabbit, for a contact time of 7 hours; during the contact time, the treated skin areas were left uncovered. The emulsion was applied in a volume of 0.5 mL/kg body weight at each dose level. The size of each exposed skin area on which the test compound emulsion was applied was about 5 x 5 cm; a Record syringe fitted with a blunted hypodermic needle was used for applying the emulsion and spreading it evenly on the exposed skin areas.
At the end of each 7-hour contact time, the treated skin areas were washed with soap and water. New growth of hair in and around the treated skin areas was removed once weekly with clippers.
The following doses of LH 30/Z were applied daily in 0.5 mL aqueous emulsion per kg body weight:
0 mg/kg body weight - Control Group
50 mg/kg body weight - Dose Group 1
250 mg/kg body weight - Dose 0roup 2

Examinations

Observations and examinations performed and frequency:

General checks:
During the study, the rabbits were inspected daily for physical appearance, behavioural patterns, appetite and condition of faeces. They were weighed prior to initiation of test compound application, and at the end of each treatment week.

Examinations for local skin compatibility:
The exposed skin areas were inspected prior to commencement of treatment and at the end of each 7-hour contact time (after removal of the test compound) for signs of inflammation (erythema and edema).

Laboratory tests:
Blood and urine samples from each rabbit were analyzed prior to initiation of test compound application and at the end of the three-week treatment period. The blood required for these analyses was withdrawn from the ear vein of each rabbit. The urine was collected from each rabbit for 16 hours overnight.

Sacrifice and pathology:

Necropsy and organ weight measurement:
Twenty-four to forty- eight hours after the final application, the rabbits were narcotized with 1.0 g Evipansodium (hexobarbital-Na) , sacrificed by exsanguination from the Vena cava caudalis, dissected and grossly examined. Heart, lung, liver, spleen, kidneys, adrenals, testes, ovaries and thyroid were weighed.

Histopathology:
Tissues processed for histopathological examination were obtained from several rabbits of the three groups. From each rabbit, two portions of dorsal skin (one portion from the treated area and one portion from the skin around the treated area) were fixed in Bouin's solution, embedded in Paraplast, sectioned, and stained with hemalum and eosin (HE). The tissues from the rabbits that died intercurrently were fixed in 10 % Formol. Additionally, the following tissues from rabbits of the control group and the highest dose group (250 mg/kg) were similarly processed for histopathological examination: genitals (testes, epidid3nnides resp. ovaries, uterus), heart, spleen, adrenals, kidney, liver, lung and thyroid. Portions of the liver were additionally fixed in Formol-calcium and frozen sections cut at 16 M, were stained for fat with Oil Red 0 (ORO). Kidney sections were additionally stained with PAS.

Other examinations:

Urinalyses
pH, protein, sugar, blood (haemoglobin): semiquantitatively tested with Combi-Uristix reagents
Urobilinogen: Urobilistix reagents. Results are expressed in Ehrlich units/100 mL urine. Sensitivity of 0.1 Ehrlich units/100 mL urine.
Deposits: following 5-minute centrifugation of the urine at 2000 G, the deposit was examined microscopically at x45 magnification.
The deposit constituents (bacteria (B), epithelia (E), erythrocytes (Ery), leucocytes (L), amorphous salts (a.S.), triple phosphates (T), calcium oxalate (Co)) were graded on the following scale:
++++ = signifies very many in all fields
+++ = signifies many in all fields
++ a signifies few in some fields
+ = signifies few in deposit smear

Clinical chemistry (blood):
Aspartate aminotransferase (GOT), Alanine aminotransferase (GPT), Alkaline phosphatase (ALP),
Plasma urea (PUR), Blood sugar (BSU), Bilirubin (BILI), Protein-bound iodine (PBJ).

Haematology
Erythrocyte and leucocyte counts (ERY and LEU), Haemoglobin (RGB), Thrombocyte counts(THROM), Haematocrit (HCT), Calculation of medium cell haemoglobin (Hbg value), Calculation of medium corpuscular volume (MCV), Differential blood count on smears stained by method of WRIGHT.

Statistics:

Not specified.

Results and discussion

Results of examinations

Clinical signs:

no effects observed

Dermal irritation:

effects observed, non-treatment-related

Description (incidence and severity):

Pimples and a mild bluish-red discoloration extending also beyond the treated area appeared on the dorsal skin after 13 applications in one rabbit and after 10 applications in another one. After 5 to 8 applications, 5 rabbits developed mild rhinitis.
No macroscopic variations from the norm were noted in the rabbits with, intact skin. The skinfold measurements also did not provide any indication of edema due to application of the test compound. No differences were seen between control rabbits and treated rabbits. In all the rabbits with abraded skin, slight to moderate erythema and edema caused by the abrasion appeared before test compound, application was initiated. These inflammations induced by abrasion of the skin began to clear during the first four days of the experiment and healed in Week 2 with formation of crusts.
There was no significant difference among the groups.

Mortality:

mortality observed, non-treatment-related

Description (incidence):

Three male rabbits died during the experiment. The gross pathology findings for two of them were indicative of pleuropneumonitis. One rabbit had a severe
pneumonitis. Microbiological examinations of the tissues from two rabbits revealed the presence of Escherichia coli and Staphylococcus aureus.

Body weight and weight changes:

effects observed, non-treatment-related

Description (incidence and severity):

Comparison of the body weights of the rabbits in the different groups did not reveal any group-specific differences. Slight weight depressions were noted transiently for rabbits of each group. These depressions are attributable to the
effects of manipulation and immobilization and to the withdrawal of food and water during the 7-hour contact times. Under the described experimental conditions, body weight development was thus normal.

Food consumption and compound intake (if feeding study):

not examined

Food efficiency:

not examined

Water consumption and compound intake (if drinking water study):

not examined

Ophthalmological findings:

not examined

Haematological findings:

no effects observed

Description (incidence and severity):

No variations from normal were noted, i.e. there were no group-specific alterations considered attributable to application of the test compound.
As expected on the basis of experience, the range of the numbers of thrombocytes counted in rabbit's blood was wider than that for the other haematological parameters. The average thrombocyte counts were all within the range considered normal in the determinations.

Clinical biochemistry findings:

effects observed, non-treatment-related

Description (incidence and severity):

Lower treatment-unrelated alkaline phosphatase activities in blood serum were noted in all groups at the terminal analysis as compared with the pre-treatment analysis. The values for protein-bound iodine were comparable in all groups at termination of treatment, and did not provide any indication of possible thyroid hypofunction.

Endocrine findings:

not examined

Urinalysis findings:

no effects observed

Description (incidence and severity):

No variations from normal and no group- specific differences were seen.

Behaviour (functional findings):

no effects observed

Description (incidence and severity):

All rabbits had a normal behaviour.

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

effects observed, non-treatment-related

Description (incidence and severity):

The absolute and relative organ weights were very largely within the normal range. Large individual variations were noted for the thyroid weights, but no treatment-related, group-specific differences were seen. Significant differences
were noted for the lung weights in some rabbits, attributable to the lung edemas.
Slight increases in absolute and relative liver weights were noted for the treated female rabbits.

Gross pathological findings:

effects observed, non-treatment-related

Description (incidence and severity):

Gross pathology did not reveal any group- specific alterations.
The following treatment-unrelated effects were seen in the different groups:
lung edemas, lung partially hardened or nodose, kidney alterations (scarred indurations or cysts), spleen with rough surface, uterus wall thickened, testes atrophied

Neuropathological findings:

not examined

Histopathological findings: non-neoplastic:

effects observed, non-treatment-related

Description (incidence and severity):

No alterations attributable to treatment with the test item were seen.
Very minimal thickening of the epidermis of the abraded skin was seen in one female rabbit. In some rabbits, minimal focal cell infiltrations were seen either in the corium of the treated skin or in the skin adjacent to the treated area.
Effects of a nonspecific inflammation, present mainly in lung, heart, kidney and liver, and final pulmonary edemas were seen in rabbits of both groups. The rabbits that died intercurrently, had severe pneumonitis. In one male rabbit of the control group, liver necroses were also observed.

Histopathological findings: neoplastic:

not examined

Other effects:

not examined

Effect levels

Key result

Dose descriptor:

NOAEL

Effect level:

250 mg/kg bw/day

Based on:

test mat.

Sex:

male/female

Basis for effect level:

body weight and weight gain

clinical signs

mortality

Remarks on result:

other: No adverse effects up to the highest dose tested.

Target system / organ toxicity

Key result

Critical effects observed:

no

Any other information on results incl. tables

Tables of results are provided in the overall remarks section below.

Applicant's summary and conclusion

Conclusions:

From the results of the 3-week dermal toxicity experiment on rabbits, it is concluded that the test item doses of up to and including 250 mg per kg body weight per day were tolerated by the rabbits without having any damaging effects.

Executive summary:

In a three-week subacute dermal cumulative toxicity study on rabbits, the test item was evaluated for local and systemic compatibility.

The test compound was applied once daily, as an aqueous emulsion, for a 7-hour contact time each day on 15 consecutive work days, to the clipped skin on the back and flanks of rabbits, at the following doses:
0 mg/kg body weight - Control group
50 mg/kg body.weight - Low Dose Group 
250 mg/kg body weight - High Dose Group 
Each test group consisted of 6 male and 6 female rabbits, of which 3 had an intact skin and 3 had an abraded skin.
No alterations attributable to application of the test compound were seen on the treated skin areas.
Clinical observations, haematology, clinical chemistry, organ weight measurements, gross pathology and histopathology provided no indications of any treatment-related systemic tissue damage or harmful effects on body functions. Thyroid function in the rabbits was not affected by treatment with the test compound.
Therefore, in the subacute dermal toxicity study on rabbits, the no-untoward-effect dose was 250 mg test item per kg body weight per day.