Adipic acid, ammonium salt

Eye irritation

Administrative data

Endpoint:

eye irritation: in vitro / ex vivo

Remarks:

ex vivo

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:

2018

Report date:

2018

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 438 (Isolated Chicken Eye Test Method for Identifying i) Chemicals Inducing Serious Eye Damage and ii) Chemicals Not Requiring Classification for Eye Irritation or Serious Eye Damage)

Version / remarks:

25 June 2018

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

1

Reference substance name:

Adipic acid, ammonium salt

EC Number:

242-809-3

EC Name:

Adipic acid, ammonium salt

Cas Number:

19090-60-9

Molecular formula:

C6H10O4.xH3N

IUPAC Name:

ammonium 5-carboxypentanoate

Test material form:

solid: crystalline

Test animals / tissue source

Species:

chicken

Strain:

other: ROSS 308

Remarks:

chiken eyes

Test system

Vehicle:

unchanged (no vehicle)

Controls:

yes

yes, concurrent positive control

yes, concurrent negative control

Amount / concentration applied:

30 mg / eyes

Duration of treatment / exposure:

10 s

Observation period (in vivo):

30, 75, 120,180 and 240 minutes after the post-treatment rinse.

Duration of post- treatment incubation (in vitro):

na

Number of animals or in vitro replicates:

3

Details on study design:

Treatment
After the zero reference measurements, one out of three test item treated eyes was taken out
of its chamber and placed on a layer of tissue with the cornea facing upwards. The eye was
held in horizontal position over a container to catch waste, while the test item was applied
onto the centre of the cornea. The test item was applied in an amount of 30 mg by
attempting to cover the cornea surface uniformly with the test substance, while taking care
not to damage or touch the cornea with the application equipment. This procedure was
repeated for each test item treated eye.
The three positive control eyes were treated in a similar way with 30 mg Imidazole.
One negative control eye was treated with saline solution. The saline solution was applied in
a volume of 30 µL from micropipette, in such a way that the entire surface of the cornea was
covered with negative control, taking care not to damage or touch the cornea with the
application equipment.

Test item removal
The time of application was monitored, then after an exposure period of 10 seconds from the
end of the application the cornea surface was rinsed thoroughly with 20 mL saline solution
at ambient temperature, while taking care not to damage the cornea but attempting to
remove all the residual test item if possible. The eye in the holder was then returned to its
chamber. The time while the eye was out of the chamber was limited to the minimum.
Imidazole was stuck on the corneas’ surface in all eyes at 30 minutes after the posttreatment rinse. The gentle rinsing with 20 mL saline was performed in all Imidazole treated
eyes after the 30, 75, 120 and 180 minutes of observation. Imidazole treated cornea surfaces
were not totally cleared at 240 minutes after the post-treatment rinse in the first and
additional experiment.

Results and discussion

In vitro

Results

Irritation parameter:

in vitro irritation score

Vehicle controls validity:

not applicable

Negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

other: Overall ICE Class: 2xI, 1xII

Other effects / acceptance of results:

In this ICET, Ammonium Adipate did not cause ocular corrosion or severe irritation in the
enucleated chicken eyes in both cases. The overall ICE class was 2xI, 1xII in the first
experiment and 3x I in the additional experiment.
Positive and negative controls showed the expected results. The experiment is considered to
be valid.
In this in vitro eye irritation study, using the Isolated Chicken Eye model with
Ammonium Adipate, no ocular corrosion or severe irritation potential was observed.
The overall ICE score was 2xI, 1xII in the first and it was 3xI in the additional
experiment.
According to the guideline OECD 438, Ammonium Adipate is categorized as “No
Category”.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

In this ICET, Ammonium Adipate did not cause ocular corrosion or severe irritation in the
enucleated chicken eyes in both cases. The overall ICE class was 2xI, 1xII in the first
experiment and 3x I in the additional experiment.
Positive and negative controls showed the expected results. The experiment is considered to
be valid.
In this in vitro eye irritation study, using the Isolated Chicken Eye model with
Ammonium Adipate, no ocular corrosion or severe irritation potential was observed.
The overall ICE score was 2xI, 1xII in the first and it was 3xI in the additional
experiment.
According to the guideline OECD 438, Ammonium Adipate is categorized as “No
Category”.

Executive summary:

The purpose of this Isolated Chicken Eye Test (ICET) was to evaluate the potential ocular
corrosivity and irritancy of the test item Ammonium Adipate by its ability to induce toxicity
in enucleated chicken eyes. The test compound was applied in a single dose (30 mg/eye)
onto the cornea of isolated chicken eyes in order to potentially classify the test compound as
either 1: causing "serious eye damage" (category 1 of the Globally Harmonised System for
the Classification and Labelling of Chemicals (GHS)), or 2: not requiring classification for
eye irritation or serious eye damage according to the GHS. Tested corneas were evaluated
pre-treatment and at approximately 30, 75, 120, 180, and 240 minutes after the posttreatment rinse. The endpoints evaluated were corneal opacity, swelling, fluorescein
retention, and morphological effects. All of the endpoints, with the exception of fluorescein
retention (which was determined only at pre-treatment and 30 minutes after test substance
exposure) were determined at each of the above time points.
According to the first experiment results the test item showed negative outcome (GHS NC).
Based on the OECD 438 additional experiment necessary to confirm or discard the negative
outcome.
The test item and Imidazole (positive control) was grounded before use in the study. The test
item and positive control applied in an amount of 30 mg/eye by powdering the entire surface
of the cornea attempting to cover the cornea surface uniformly with the test substance or
positive control. Three test item treated eyes and three positive control eyes were used in in
each experiment.
One negative control eye was treated with 30 µL saline solution in each experiment.
After an exposure period of 10 seconds from the end of the application the cornea surface
was rinsed thoroughly with ~20 mL saline solution at ambient temperature and this
procedure was repeated for each eye.
Imidazole was stuck on the corneas’ surface in all eyes at 30, 75, 120, 180 and 240 minutes
after the post-treatment rinse in the first and additional experiment. Imidazole treated cornea
surfaces were not totally cleared at 240 minutes after the post-treatment rinse in the first and
additional experiment.
In this ICET, Ammonium Adipate did not cause ocular corrosion or severe irritation in the
enucleated chicken eyes in both cases. The overall ICE class was 2xI, 1xII in the first
experiment and 3x I in the additional experiment.
Positive and negative controls showed the expected results. The experiment is considered to
be valid.
In thisin vitroeye irritation study, using the Isolated Chicken Eye model with
Ammonium Adipate, no ocular corrosion or severe irritation potential was observed.
The overall ICE score was 2xI, 1xII in the first and it was 3xI in the additional
experiment.
According to the guideline OECD 438, Ammonium Adipate is categorized as “No
Category”.