Nitric acid, ammonium calcium salt

Endpoint summary

Description of key information

No reliable skin irritation study with CN-Nitcal is present. In a reliable study with the read-across substance Nitcal-K (OECD 404, B.4, EPA and JMAFF) no irriation was observed.

An in vivo eye irritation study (OECD 405) with CN-Nitcal itself did show severe eye irritating effects in rabbits.

The read-across rationale can be found in the document attached to the target record.

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

Study period:

January, 2007

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

The study has been performed according to OECD and/or EC guidelines and according to GLP principles. However, since the study was performed with a substance analogue and the data are read across, the Klimisch score is 2.

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.4 (Acute Toxicity: Dermal Irritation / Corrosion)

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2500 (Acute Dermal Irritation)

Qualifier:

according to guideline

Guideline:

other: JMAFF (2000) including recent revisions

GLP compliance:

yes

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Harlan, Horst, The Netherlands
- Age at study initiation: at least 6 weeks
- Weight at study initiation: at least 1.0 kg
- Housing: individually in labelled cages with perforated floors
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19-23
- Humidity (%): 31-58
- Air changes (per hr): 15
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: 09 January 2007 To: 26 January 2007

Type of coverage:

semiocclusive

Preparation of test site:

shaved

Vehicle:

water

Controls:

no

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (weight with unit): 0.5 grams
The test material was moistened with 0.4 ml of water

Duration of treatment / exposure:

4 hours

Observation period:

up to 72 hours after removal of dressings

Number of animals:

3 males

Details on study design:

TEST SITE
- Area of exposure: 150 square cm
- % coverage: not indicated
- Type of wrap if used: metalline patch applied to the skin of one flank wrapped around the abdomen and secured with elastic bandage

REMOVAL OF TEST SUBSTANCE
- Washing (if done): yes, with tap water
- Time after start of exposure: 4 hours

SCORING SYSTEM: numerical scoring system for erythema and eschar formation (0-4) and for oedema formation (0-4)

Irritation parameter:

erythema score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

fully reversible

Irritation parameter:

edema score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

fully reversible

Irritant / corrosive response data:

No skin irritation was seen.

Other effects:

No symptoms of systemic toxicity, no mortality was seen.

Interpretation of results:

GHS criteria not met

Conclusions:

Based on the results of a skin irritation study in rabbits, Nitcal/K does not have to be classified or labelled for skin irritation according to Regulation (EC) 1272/2008 and under GHS.

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

Study period:

26 April 2010 to 17 May 2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2400 (Acute Eye Irritation)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.5 (Acute Toxicity: Eye Irritation / Corrosion)

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: Japanese Ministry of Agriculture, Forestry and Fisheries (JMAFF), 12 Nousan, Notification No 8147, November 2000, including the most recent partial revisions.

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: Harlan, Belton, Leics, England
- Age at study initiation: Animal used within the study was at least 6 weeks old
- Weight at study initiation: body weight was at least 1.0 kg.
- Housing: labeled cage with perforated floor (Ebeco, Germany, dimensions 67 x 62 x 55 cm) and shelter (Ebeco, Germany, dimensions 40 x 32 x 23 cm).
- Diet (e.g. ad libitum): Pelleted diet for rabbits (Global Diet 2030 from Harlan Teklad®, Mucedola, Milanese, Italy) approximately 100 grams per day. Hay (TecniLab-BMI BV, Someren, The Netherlands) was provided at least three times a week.
- Water (e.g. ad libitum): Free access to tap water.
- Acclimatization period: at least 5 days before start of treatment under laboratory conditions.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 18.6 ¿ 19.4ºC
- Humidity (%): 43 - 68%
- Air changes (per hr): 15
- Photoperiod (hrs dark / hrs light): 12 hours artificial fluorescent light and 12 hours darkness per day

IN LIFE DATES: From: 26 April 2010 To:17 May 2010

Vehicle:

unchanged (no vehicle)

Controls:

other: One eye of the animal remained untreated and served as the reference control.

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 70.7 mg

Duration of treatment / exposure:

Single instillation on Day 1

Observation period (in vivo):

The eyes of the animal were examined approximately 1, 24, 48 and 72 hours and 7, 14 and 21 days after instillation of the test substance.

Number of animals or in vitro replicates:

1 male

Details on study design:

STUDY DESIGN
The study was performed in a stepwise manner and was started by treatment of a single rabbit (sentinel). Based on the irreversibility of the ocular lesions observed during the study in the first animal (21 day of observation) and the two further rabbits assigned to the study were not treated.

TREATMENT
On test Day 1, 70.7 mg of the test substance (a volume of approximately 0.1 mL) was instilled in the conjunctival sac of an eye of one animal after gently pulling the lower lid away from the eyeball. The lids were then gently held together for about one second to prevent loss of the test substance. The other eye remained untreated and served as the reference control.

Immediately after the 24-hour observation, a solution of 2% fluorescein (Merck, Darmstadt, Germany) in water (adjusted to pH 7.0) was instilled into both eyes of the animal to quantitatively determine corneal epithelial damage. This procedure was repeated to assess recovery. Any bright green stained area, indicating epithelial damage, was estimated as a percentage of the total corneal area.

After the final observation, the animal was sacrificed by intra-venous injection of Euthasol® 20% (AST Farma BV, Oudewater, The Netherlands).

REMOVAL OF TEST SUBSTANCE
- Washing (if done): No

OBSERVATION
The irritation was assessed according to the following numerical scoring system. At each observation, the highest scores given were recorded:

SCORING SYSTEM:
CORNEAL IRRITATION
Opacity: degree of density (area most dense taken for reading)
0: No ulceration or opacity (may include slight dulling of normal luster)
1: Scattered or diffuse areas of opacity, details of iris clearly visible
2: Easily discernible translucent area, details of iris slightly obscured
3: Nacreous area, no details of iris visible, size of pupil barely discernible
4: Opaque cornea, iris not discernible through the opacity

Area of cornea involved:
0: No ulceration or opacity
1: One quarter or less but not zero
2: Greater than one quarter, but less than half
3: Greater than half, but less than three quarters
4: Greater than three quarters, up to whole area

IRIS
0: Normal
1: Markedly deepened rugae, congestion, swelling, moderate circumcorneal hyperaemia,
or injection, any of these or combination thereof, iris still reacting to light
(sluggish reaction is positive)
2: No reaction to light, hemorrhage, gross destruction (any or all of these)

CONJUNCTIVAL IRRITATION
Redness (refers to palpebrae and sclera, excluding cornea and iris):
0: Blood vessels normal
1: Some blood vessels definitely hyperaemic (injected)
2: Diffuse, crimson color, individual vessels not easily discernible
3: Diffuse beefy red

Chemosis (refers to lids and/or nictitating membranes):
0: No swelling
1: Any swelling above normal (includes nictitating membranes)
2: Obvious swelling with partial eversion of lids
3: Swelling with lids about half closed
4: Swelling with lids more than half closed

Discharge:
0: No discharge (may include small amounts observed in inner canthus of normal animals)
1: Any amount different from normal and/or lacrimation
2: Discharge with moistening of the lids and hairs just adjacent to lids
3: Discharge with moistening of the lids and hairs (considerable area around the eye)

Where standard lighting was considered inadequate for observing minor effects, eye examinations were performed using an ophthalmic examination lamp.
In cases of equivocal results when comparing the treated and untreated eyes, the illustrated guide from the Consumer Product Safety Commission, Washington, D.C. 20207 was used for additional control purposes.

Irritation parameter:

cornea opacity score

Remarks:

opacity

Basis:

animal #1

Time point:

24/48/72 h

Score:

1

Max. score:

4

Reversibility:

not reversible

Irritation parameter:

cornea opacity score

Remarks:

area

Basis:

animal #1

Time point:

24/48/72 h

Score:

3

Max. score:

4

Reversibility:

not fully reversible within: 21 days, score 1

Irritation parameter:

iris score

Basis:

animal #1

Time point:

24/48/72 h

Score:

1

Max. score:

2

Reversibility:

fully reversible within: 14 days

Irritation parameter:

conjunctivae score

Remarks:

redness

Basis:

animal #1

Time point:

24/48/72 h

Score:

3

Max. score:

3

Reversibility:

not fully reversible within: 21 days, score 2

Irritation parameter:

chemosis score

Basis:

animal #1

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

not fully reversible within: 21 days, score 1

Irritation parameter:

conjunctivae score

Remarks:

discharge

Basis:

animal #1

Time point:

24/48/72 h

Score:

2

Max. score:

3

Reversibility:

not fully reversible within: 21 days, score 1

Irritant / corrosive response data:

Instillation of 70.7 mg of CN-Nitcal (a volume of approximately 0.1 mL) into an eye of one rabbit resulted in effects on the cornea, iris and conjunctivae.
The corneal injury consisted of opacity (maximum grade 4) and epithelial damage (maximum 75% of the corneal area). As a result of the corneal injury, pannus (neovascularization of the cornea) was apparent 7 days after instillation up to the end of the observation period. The corneal injury did not resolve within the observation period of 21 days.
Iridial irritation grade 1 was observed and resolved within 14 days.
The irritation of the conjunctivae consisted of redness, chemosis and discharge and did not resolve within the observation period of 21 days.

see also attached tables.

Other effects:

Corrosion:
There was no evidence of ocular corrosion.

Coloration / Remnants:
No staining of (peri) ocular tissues by the test substance was observed and no test substance remnants were seen. However, heavy discharge and swelling of the eyelids might have hampered the scoring of test substance remnants behind the lower eyelid.

Toxicity / Mortality:
No symptoms of systemic toxicity were observed in the animal during the test period and no mortality occurred.

Interpretation of results:

Category 1 (irreversible effects on the eye) based on GHS criteria

Remarks:

Labeled as H318: Causes serious eye damage

Conclusions:

Based on the persistence of the effects up to the end of the observation time of 21 days CN-Nitcal should be classified:
- according to the Globally Harmonized System of Classification and Labeling of Chemicals (GHS) of the United Nations (2007) as: having irreversible effects on the eyes (Category 1).

- according to the Regulation (EC) No 1272/2008 on classification, labeling and packaging of substances and mixtures, as Irreversible effects on the eye (Category 1) and labeled as H318: Causes serious eye damage.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Skin

No reliable study with nitric acid, ammonium calcium salt itself is present. However, in a reliable skin irritation study in rabbits (performed comparable to OECD 404, EU B.4, EPA and JMAFF) with Nitcal-K (potassium pentacalcium nitrate decahydrate), no signs of skin irriation was observed up to 72 hours. No mortality and no signs of toxicity were seen.

Eye

With nitric acid, ammonium calcium salt itself an in vitro eye irritation study according to OECD guideline 437 did not show irritating effects. In a reliable in vivo study in rabbits performed according to OECD 405, EU B.5 (and EPA and JMAFF) it is shown that CN-Nitcal is irritating. Instillation of 70.7 mg of CN-Nitcal (a volume of approximately 0.1 mL) into an eye of one rabbit resulted in effects on the cornea, iris and conjunctivae. The corneal injury consisted of opacity (maximum grade 4) and epithelial damage (maximum 75% of the corneal area). As a result of the corneal injury, pannus (neovascularization of the cornea) was apparent 7 days after instillation up to the end of the observation period. The corneal injury did not resolve within the observation period of 21 days. Iridial irritation grade 1 was observed and resolved within 14 days. The irritation of the conjunctivae consisted of redness, chemosis and discharge and did not resolve within the observation period of 21 days. Therefore, no more animals were tested.

Justification for selection of skin irritation / corrosion endpoint:

One in vivo study on the read-across substance Nitcal/K is available. The study has been performed according to OECD and/or EC guidelines and according to GLP principles. However, since the study was performed with a substance analogue and the data are read across, the Klimisch score is 2.

Justification for selection of eye irritation endpoint:

One in vivo study is available.

Effects on eye irritation: irritating

Justification for classification or non-classification

With regard to skin irritation nitric acid, ammonium calcium salt does not have to be classified according to the CLP Regulation.

Nitric acid, ammonium calcium salt does have to be classified for eye irritation according to the CLP Regulation with Cat.1 (irriversible effects on the eye), H318 'Causes serious eye damage'.