Ammonium nitrate

Endpoint summary

Description of key information

Based on reliable skin and eye irritation studies with ammonium nitrate, the substance appears to be not irritating to skin, but irritating to eyes.

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Endpoint:

skin irritation: in vivo

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

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

GLP compliance:

no

Remarks:

study performed before GLP was in place.

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Bantin and Kingman Ltd., The Field Station, Grimston, Aldbrough, Hull, HU11 4QE
- Weight at study initiation: 2.72-3.23 kg
- Housing: individually in grid floor cages
- Diet (e.g. ad libitum): free access
- Water (e.g. ad libitum):free access
- Acclimation period: at least 3 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19-22 C
- Humidity (%): 44-53%
- Air changes (per hr): single air conditioned
- Photoperiod (hrs dark / hrs light):14 hours artificial light (06.00-20.00)

Type of coverage:

occlusive

Preparation of test site:

other: clipped

Vehicle:

water

Controls:

other: each animal served as its own control

Amount / concentration applied:

TEST MATERIAL
- Concentration (if solution): 0.5 g moistened with water

Duration of treatment / exposure:

4 hours

Observation period:

up to 72 hours

Number of animals:

3

Details on study design:

TEST SITE
- Area of exposure: 6 cm2
- Type of wrap if used: covered with gauze patch and plastic collar around the neck


REMOVAL OF TEST SUBSTANCE
- Washing (if done): wiped with disposable paper towel moistened with water.
- Time after start of exposure: 4 hours


SCORING SYSTEM: Draize

Irritation parameter:

erythema score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

4

Irritation parameter:

edema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

fully reversible

Irritation parameter:

edema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

fully reversible

Irritation parameter:

edema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

fully reversible

Irritation parameter:

primary dermal irritation index (PDII)

Basis:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

5

Interpretation of results:

GHS criteria not met

Conclusions:

P0018 (ammonium nitrate) was regarded as non-irritant to rabbit skin.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Eye irritation

Link to relevant study records

Reference

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

GLP compliance:

not specified

Species:

rabbit

Duration of treatment / exposure:

24 hr / 100 mg

Observation period (in vivo):

7 days

Number of animals or in vitro replicates:

3

Irritation parameter:

cornea opacity score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0.3

Reversibility:

fully reversible within: 2 days

Irritation parameter:

cornea opacity score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0.3

Reversibility:

fully reversible within: 2 days

Irritation parameter:

cornea opacity score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Irritation parameter:

iris score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0.3

Reversibility:

fully reversible within: 2 days

Irritation parameter:

iris score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Irritation parameter:

iris score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Irritation parameter:

conjunctivae score

Basis:

animal #1

Time point:

24/48/72 h

Score:

3

Reversibility:

fully reversible within: 10 days

Irritation parameter:

conjunctivae score

Basis:

animal #2

Time point:

24/48/72 h

Score:

3

Reversibility:

fully reversible within: 7 days

Irritation parameter:

conjunctivae score

Basis:

animal #3

Time point:

24/48/72 h

Score:

2.3

Reversibility:

fully reversible within: 7 days

Irritation parameter:

chemosis score

Basis:

animal #1

Time point:

24/48/72 h

Score:

1

Reversibility:

fully reversible within: 7 days

Irritation parameter:

chemosis score

Basis:

animal #2

Time point:

24/48/72 h

Score:

1

Reversibility:

fully reversible within: 7 days

Irritation parameter:

chemosis score

Basis:

animal #3

Time point:

24/48/72 h

Score:

1

Reversibility:

fully reversible within: 4 days

Interpretation of results:

Category 2A (irritating to eyes) based on GHS criteria

Remarks:

Classified as Category 2 according to Regulation (EC) No 1272/2008

Conclusions:

Based on the effects seen on the conjuctiva in all three animals tested (redness score: average 1, 2 and 3 days) the substance should be considered as being irritating to the eye (Category 2A).

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

In a reliable skin irritation study in rabbits (performed similar to OECD 404) with ammonium nitrate, no signs of skin irritation were observed up to 72 hours. However, in an eye irritation study in rabbits (similar to OECD 405) with ammonium nitrate, clear irritation was observed with conjunctivae having scores above 2. However the effects were fully reversible within 7 -10 days. Irritation to the iris and cornea was limited (average scores 0.3), however the chemosis score had an average of 1. In a validation study the in vitro slug mucosal irritation assay was used to study ammonium nitrate.

Justification for classification or non-classification

Ammonium nitrate does not have to be classified for skin irritation according to Regulation (EC) No 1272/2008. However, for eye irritation the substance does have to be classified. According to the CLP Regulation as Eye irritant Cat 2, H319 causes serious eye irritation.