2-hydroxyethyliminodi(acetic acid)

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2002

Report date:

2002

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of study:

Buehler test

Justification for non-LLNA method:

Available historical study

Test material

Test material information

Constituent 1

Reference substance name:

Disodium 2-hydroxyethyliminodi(acetate)

EC Number:

205-187-4

EC Name:

Disodium 2-hydroxyethyliminodi(acetate)

Cas Number:

135-37-5

Molecular formula:

C6H11NO5.2Na

IUPAC Name:

disodium 2,2'-[(2-hydroxyethyl)imino]diacetate

Test material form:

liquid

Specific details on test material used for the study:

The test article was received from the Sponsor and identified as follows:

Sponsor’s ID: XUS 40855.01, Lot No.: PK2001D602

Physical Description: Clear colorless liquid via pipet; light pale yellow liquid via bulk container

Purity: 27% Na2HEIDA as the active ingredient

In vivo test system

Test animals

Species:

guinea pig

Strain:

Hartley

Sex:

male/female

Details on test animals and environmental conditions:

February 7, 2002, from Hilltop Lab Animals, Inc., Scottdale, PA. Upon receipt, plastic ear tags displaying unique identification numbers were used to individually identify the
animals. Cage cards displaying at least the study number, animal number and sex were affixed to each cage. The animals were housed individually in suspended stainless steel cages. All housing and care were based on the standards recommended by the Guide for the Care and Use of Laboratory Animals

The animal room temperature and relative humidity ranges were 65-73EF (18-23°C) and 32-57%, respectively. Environmental control equipment was monitored
and adjusted as necessary to minimize fluctuations in the animal room environment. Light timers were set to maintain a 12-hour light/12-hour dark cycle and room ventilation was set to produce 10-15 air changes/hour. The room temperature and relative humidity were recorded a minimum of once daily.

The animals chosen for study use were arbitrarily selected from healthy stock animals to avoid potential bias. All animals received a detailed pretest observation prior to dosing. Only healthy animals were chosen for study use. Females were nulliparous and nonpregnant. For the range-finding study, the male animals were approximately 8
weeks of age and weighed 486-496 g prior to dosing and the female animals were approximately 10 weeks of age and weighed 437-484 g prior to dosing. For the main
sensitization study, the male animals were approximately 8 weeks of age and weighed 469-506 g prior to Induction I and the female animals were approximately 9 weeks of age and weighed 451-493 g prior to Induction.

Study design: in vivo (non-LLNA)

Induction

Induction 1

Route:

epicutaneous, occlusive

Vehicle:

unchanged (no vehicle)

Concentration / amount:

0.3 ml

Day(s)/duration:

Day 1 - 6 hours

Adequacy of induction:

highest technically applicable concentration used

Induction 2

Route:

epicutaneous, occlusive

Vehicle:

unchanged (no vehicle)

Concentration / amount:

0.3 ml

Day(s)/duration:

7 - 6 hours

Adequacy of induction:

highest technically applicable concentration used

Induction 3

Route:

epicutaneous, occlusive

Vehicle:

unchanged (no vehicle)

Concentration / amount:

0.3 ml

Day(s)/duration:

Day 13 - 6 hours

Adequacy of induction:

highest technically applicable concentration used

Challenge

No.:

#1

Route:

epicutaneous, occlusive

Vehicle:

unchanged (no vehicle)

Concentration / amount:

0.3 ml

Day(s)/duration:

27 - 6 hours

Adequacy of challenge:

highest non-irritant concentration

No. of animals per dose:

10 male/10 female

Details on study design:

Topical Range–Finding Study
Dosing
On the day prior to dose administration, four topical range-finding guinea pigs were weighed and the hair removed from the right and left sides of the animals with a small animal clipper. Care was taken to avoid abrading the skin during the clipping
procedures.
On the following day, four concentrations of the test article (25,50,75,100%) were prepared and each concentration was applied (0.3 ml) to the clipped area of each topical range-finding animal.
Following chamber application, the trunk of the animal was wrapped with elastic wrap which was secured with adhesive tape to prevent removal of the chambers and the animal was returned to its cage.
Approximately six hours after chamber application, the binding materials were removed. The test sites were then wiped with gauze moistened with deionized water followed by dry gauze to remove test article residue.
The animals were then returned to their cages.
Dermal Observations
The test sites of the range-finding animals were graded for irritation at approximately 24 and 48 hours following chamber application using the Dermal Grading System.
Clinical Observations
Any unusual observations and mortality were recorded. The topical range-finding animals were observed for general health/mortality twice daily, once in the morning and once in the afternoon.
Body Weights
Individual body weights were obtained for the topical range-finding animals on the day prior to dosing.
Scheduled Euthanasia
Following the final scoring interval, all range-finding animals were euthanized by carbon dioxide inhalation. Gross necropsy examinations were not required for these animals.

Sensitization Study
Preliminary Procedures
On the day prior to each dose administration, the guinea pigs had the hair removed with a small animal clipper. Care was taken to avoid abrading the skin during the clipping procedures.
Dosing
A dose of 0.3 mL of the test article was placed on a 25mm Hilltop chamber backed by adhesive tape (occlusive patch). The chambers were then applied to the clipped surface as quickly as possible.
Following chamber application, the trunk of the animal was wrapped with elastic wrap which was secured with adhesive tape to prevent removal of the chamber and the animal was returned to its cage.
Induction
On the day prior to the first induction dose administration (day -1), all test and control animals were weighed and the hair was removed from the left side of the test animals.
On the day following clipping (day 0), chambers were applied, the induction procedure was repeated on study day 7 and on study day 13 so that a total of three consecutive induction exposures were made to the test animals.
Challenge
On the day prior to challenge dose administration, the test and challenge control animals were weighed and the hair was removed from the right side of the animals. On the day following clipping (day 27), chambers were applied.
Test Article Removal
Approximately six hours after chamber application, the binding materials were removed. The test sites were wiped with gauze moistened in deionized water, followed by dry gauze, to remove test article residue. The animals were then returned to their cages.
Dermal Observations
The test sites were graded for irritation at approximately 24 and 48 hours following chamber application (induction) or chamber removal (challenge) using the Dermal Grading System.
Clinical Observations
Any unusual observations and mortality were recorded. The animals were observed for general health/mortality twice daily, once in the morning and once in the afternoon.
Body Weights
Individual body weights were obtained for all sensitization study animals on the day prior to the first induction (day -1) and for the appropriate test and challenge control animals
on the day prior to challenge dosing. All sensitization study animals were also weighed prior to scheduled euthanasia.
Scheduled Euthanasia
All sensitization study animals were euthanized by carbon dioxide inhalation following each animal's final scoring interval. Gross necropsy examinations were not required for these animals.

Positive control substance(s):

yes

Results and discussion

Positive control results:

Positive control using 1-Chloro-2,4-Dinitrobenzene and a-hexylcinnamaldehyde demonstrated susceptibility of the test system to the sensitizing agents.

In vivo (non-LLNA)

Results

Results 1

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

0.3 ml/100%

No. with + reactions:

0

Total no. in group:

20

Remarks on result:

no indication of skin sensitisation

Results 2

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

0.3 ml/100%

No. with + reactions:

0

Total no. in group:

20

Remarks on result:

no indication of skin sensitisation

Results 3

Reading:

1st reading

Hours after challenge:

24

Group:

positive control

Dose level:

0.1 % DNCB in ethanol/acetone

No. with + reactions:

20

Total no. in group:

20

Remarks on result:

positive indication of skin sensitisation

Results 4

Reading:

2nd reading

Hours after challenge:

48

Group:

positive control

Dose level:

0.1 * DNCB in ethanol/acetone

No. with + reactions:

18

Total no. in group:

20

Remarks on result:

positive indication of skin sensitisation

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Skin sensitization of HEIDAA was evaluated in Hartley albino guinea pigs using OECD 406 Buehler test method. Based on the results of this study, HEIDAA is not considered to be a contact sensitizer in guinea pigs.

Executive summary:

Skin sensitization of HEIDAA was evaluated in Hartley albino guinea pigs using OECD 406 Buehler test method. Following challenge with test material, dermal scores of 0 were noted in all of the test and challenge control animals. Based on the results of this study, HEIDAA is not considered to be a contact sensitizer in guinea pigs.