Ammonium sulphamidate

Endpoint summary

Description of key information

Ammonium sulphamidate was not irritant to the skin or the eye of rabbits.

The read-across on sodium sulphamidate showed that only a mild irritation in the skin and eyes of rabbits was noted but it cleared.

Ammonium sulphamidate is therefore not classified for the skin and eye irritation endpoints.

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Reference 1

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes

Specific details on test material used for the study:

The test substance was Basensol GS, which was composed of 100% ammonium sulphamidate

Species:

rabbit

Strain:

Vienna White

Details on test animals or test system and environmental conditions:

3 young adult rabbits (2.6 to 2.8 kg each) were housed in fully air-conditioned rooms. Central air-conditioning guaranteed a range of 20-24°C for temperature and of 30-70% for relative humidity.
Day/nith rhythm of 12 hours/12 hours. Single housing.
About 250 mL tap water per animal per day and about 130 g diet per animal per day.
Acclimatization for at least one week.

Type of coverage:

semiocclusive

Preparation of test site:

clipped

Vehicle:

unchanged (no vehicle)

Controls:

yes, concurrent no treatment

Amount / concentration applied:

0.5 mL of the unchanged liquid test substance (single dose)

Duration of treatment / exposure:

4 hours

Observation period:

72 hours

Number of animals:

3 animals (2 males and 1 female)

Details on study design:

Weight determination: shortly before application of the test substance.
Application site: upper third of the back or flanks.
Readings: about 1 hour after removal of the patch, 24, 48 and 72 hours after application.
General observations: a check was made twice each workday and once saturdays, sundays and public holidays for general observations and for any dead or moribund animals.

Irritation parameter:

erythema score

Basis:

mean

Time point:

24/48/72 h

Score:

ca. 0

Irritation parameter:

edema score

Basis:

mean

Time point:

24/48/72 h

Score:

ca. 0

Interpretation of results:

GHS criteria not met

Conclusions:

Under the test conditions chosen and considering the described findings, Basensol GS (i.e. ammonium sulphamidate) does not give indication of an irritant property to the skin.

Reference 2

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

The study was performed between 23 June 2011 and 08 July 2011.

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study conducted to GLP and in compliance with agreed protocols, with no or minor deviations from standard test guidelines and/or minor methodological deficiencies, which do not effect the quality of the relevant results.

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)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2500 (Acute Dermal Irritation)

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: Japanese Ministry of Agriculture, Forestry and Fisheries (JMAFF), Testing Guidelines for Toxicology Studies, 12 NohSan No. 8147, amended 10 December 2002

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: Japanese Ministry of Health and Welfare, 1992

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Three New Zealand White (Hsdlf:NZW) strain rabbits were supplied by Harlan Laboratories UK Ltd., Leicestershire, UK.
- Age at study initiation: twelve to twenty weeks old
- Weight at study initiation: At the start of the study the animals weighed 2.18 to 2.78 kg
- Housing: The animals were individually housed in suspended cages.
- Diet (e.g. ad libitum): Free access to food (2930 Teklad Global Rabbit diet supplied by Harlan Laboratories UK Ltd., Oxon, UK) was allowed throughout the study.
- Water (e.g. ad libitum): Free access to mains drinking water was allowed throughout the study.
- Acclimation period: At least five days.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 17 to 23°C
- Humidity (%): 30 to 70%
Any occasional deviations from these targets were considered not to have affected the purpose or integrity of the study.
- Air changes (per hr): At least fifteen changes per hour
- Photoperiod (hrs dark / hrs light): Lighting was controlled by a time switch to give twelve hours continuous light (06:00 to 18:00) and twelve hours darkness.

Type of coverage:

semiocclusive

Preparation of test site:

other: clipped free of fur

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

TEST MATERIAL
For the purpose of the study the test item was ground to a powder before use.
The absorption of the test item was not determined.

At each test site a quantity of 0.5 g of the test item, moistened sufficiently with 0.5 ml of distilled water, was introduced

Duration of treatment / exposure:

3 minutes (initial animal), 1 hour (initial animal) and 4 hours (all animals)

Observation period:

72 hours plus an additional observation was made at one treated skin site on Day 7.

Number of animals:

3

Details on study design:

MEASUREMENT OF PH:
The pH of the test item was determined prior to commencement of the study and found to be as follows:
10% w/w aqueous preparation of the test item: pH 8.1 (immediately)
: pH 8.5 (after 10 minutes)


PROCEDURE:
On the day before the test each rabbit was clipped free of fur from the dorsal/flank area using veterinary clippers. Only animals with a healthy intact epidermis by gross observation were selected for the study.

One rabbit was initially treated. Three suitable sites were selected on the back of the rabbit. At each test site a quantity of 0.5 g of the test item, moistened sufficiently with 0.5 ml of distilled water, was introduced under a 2.5 cm x 2.5 cm cotton gauze patch. Each patch was secured in position with a strip of surgical adhesive tape. To prevent the animal interfering with the patches, the trunk of the rabbit was wrapped in an elasticated corset for the duration of the exposure period.

One patch was removed at each of three time points: 3 minutes, 1 hour and 4 hours after application. Any residual test item was removed by gentle swabbing with cotton wool soaked in distilled water.

After consideration of the skin reactions produced in the first animal, an additional two animals were treated with 0.5 g of test item, moistened sufficiently with 0.5 ml of distilled water. One patch was applied to the back of each rabbit and was allowed to remain in contact with the skin for a period of four hours.


SCORING SYSTEM:
Immediately following removal of the patches and approximately 1, 24, 48 and 72 hours later, the test sites were examined for evidence of primary irritation and scored according to the Draize scale (see evaluation of skin reactions below).

Any other skin reactions and clinical signs of toxicity, if present, were also recorded.

An additional observation was made at one treated skin site on Day 7 to assess the reversibility of skin reactions.

Individual bodyweights were recorded on Day 0 (the day of dosing) and at the end of the observation period.

Irritation parameter:

erythema score

Basis:

mean

Remarks:

(Animal 1 - 70542)

Time point:

other: Mean of scores at 24, 48 and 72 hours

Score:

1.7

Max. score:

4

Reversibility:

fully reversible within: 7 days

Remarks on result:

other: Results of 4 hour exposure. Light brown discolouration of the epidermis noted at 48 and 72 hours. Loss of skin elasticity noted at 72 hours.

Irritation parameter:

edema score

Basis:

mean

Remarks:

(Animal 1 - 70542)

Time point:

other: Mean of scores at 24, 48 and 72 hours

Score:

0.7

Max. score:

4

Reversibility:

fully reversible within: 7 days

Remarks on result:

other: Results of 4 hour exposure

Irritation parameter:

erythema score

Basis:

mean

Remarks:

(Animal 2 - 70657)

Time point:

other: Mean scores of 24, 48 and 72 hours

Score:

0.3

Max. score:

4

Reversibility:

fully reversible within: 48 hours

Remarks on result:

other: Results from 4 hour exposure

Irritation parameter:

edema score

Basis:

mean

Remarks:

(Animal 2 - 70657)

Time point:

other: Mean scores of 24, 48 and 72 hours

Score:

0

Max. score:

4

Remarks on result:

other: Results from 4 hour exposure

Irritation parameter:

erythema score

Basis:

mean

Remarks:

(Animal 3 - 70658)

Time point:

other: Mean of scores at 24, 48 and 72 hours

Score:

0

Max. score:

4

Remarks on result:

other: Results from 4 hour exposure

Irritation parameter:

edema score

Basis:

mean

Remarks:

(Animal 3 - 70658)

Time point:

other: Mean of scores at 24, 48 and 72 hours

Score:

0

Max. score:

4

Remarks on result:

other: Results from 4 hour exposure

Irritant / corrosive response data:

Skin Reactions

3-Minute Exposure Period:
The individual scores for erythema/eschar and oedema are given in Table 1.
No evidence of skin irritation was noted during the study.

1-Hour Exposure Period:
The individual scores for erythema/eschar and oedema are given in Table 1.
Very slight erythema was noted at the treated skin site immediately and one hour after patch removal and at the 24, 48 and 72-Hour observations.
The treated skin site appeared normal at the 7-Day observation.

4-Hour Exposure Period
The individual scores for erythema/eschar and oedema are given in Table 2.

Very slight erythema was noted at one treated skin site immediately after patch removal and at two treated skin sites one and 24 hours after patch removal. Well-defined erythema, very slight oedema and light brown discolouration of the epidermis were noted at one treated skin site at the 48 and 72-Hour observations with loss of skin elasticity also noted at this treated skin site at the 72-Hour observation.

No evidence of skin irritation was noted at one treated skin site during the study. One treated skin site appeared normal at the 48-Hour observation and the remaining treated skin site appeared normal at the 7-Day observation.

The individual mean scores for erythema and oedema required for classification according to the Globally Harmonised System of Classification and Labelling of
Chemicals were as follows:
Animal 1 (70542):
Mean score erythema/eschar formation: 1.7
Mean score for oedema formation: 0.7
Animal 2 (70657):
Mean score erythema/eschar formation: 0.3
Mean score for oedema formation: 0
Animal 3 (70658):
Mean score erythema/eschar formation: 0.0
Mean score for oedema formation: 0.0

Other effects:

Bodyweight:
Individual bodyweights and bodyweight changes are given in Table 3.
No bodyweight gain was noted in one animal. Two animals showed expected gain in bodyweight during the study.

Table 1              Individual Skin Reactions Following 3-Minute and 1-Hour Exposures

Skin Reaction	Observation Time (following patch removal)	Individual Scores - Rabbit Number and Sex
		70542Male
		3-Minute Exposure	1-Hour Exposure
Erythema/Eschar Formation	Immediately	0	1
	1 Hour	0	1
	24 Hours	0	1
	48 Hours	0	1
	72 Hours	0	1
	7 Days	0	0
Oedema Formation	Immediately	0	0
	1 Hour	0	0
	24 Hours	0	0
	48 Hours	0	0
	72 Hours	0	0
	7 Days	0	0

Table 2              Individual Skin ReactionsFollowing 4-Hour Exposure

Skin Reaction	Observation Time (following patch removal)	Individual Scores – Rabbit Number and Sex			Total
		70542Male	70657Male	70658Male
Erythema/Eschar Formation	Immediately	1	0	0	(1 )
	1 Hour	1	1	0	( 2 )
	24 Hours	1	1	0	2
	48 Hours	2Br	0	0	( 2 )
	72 Hours	2BrLe	0	0	2
	7 Days	0	-	-	( 0 )
Oedema Formation	Immediately	0	0	0	( 0 )
	1 Hour	0	0	0	( 0 )
	24 Hours	0	0	0	0
	48 Hours	1	0	0	( 1 )
	72 Hours	1	0	0	1
	7 Days	0	-	-	( 0 )
Sum of 24 and 72-hour Readings (S)       :          5
Primary Irritation Index (S/6)                   :          5/6 = 0.8
Classification                                        :          MILD IRRITANT

(   ) =  Total values not used for calculation of primary irritation index

Br=     Light brown discolouration of the epidermis

Le=     Loss of skin elasticity

- =       Not applicable

Table 3              Individual Bodyweights and Bodyweight Changes

Rabbit Number and Sex	Individual Bodyweight (kg)		Bodyweight Change (kg)
70542Male	Day 0	Day 7	0.15
	2.41	2.56
70657Male	Day 0	Day 3	0.04
	2.78	2.82
70658Male	Day 0	Day 3	0.00
	2.18	2.18

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The test item produced a primary irritation index of 0.8 and was classified as a MILD IRRITANT to rabbit skin according to the Draize classification scheme. No corrosive effects were noted.

The test item produced a maximum individual mean score of 1.7 and therefore did not meet the criteria for classification according to the Globally Harmonised System of Classification and Labelling of Chemicals.

Executive summary:

Introduction. 

The study was performed to assess the irritancy potential of the test item to the skin of the New Zealand White rabbit. The method was designed to be compatible with the following:

- OECD Guidelines for the Testing of Chemicals No. 404 “Acute Dermal Irritation/Corrosion” (adopted 24 April 2002)

- Method B4 Acute Toxicity (Skin Irritation) of Commission Regulation (EC) No. 440/2008

- United States Environmental Protection Agency Health Effects Tesat Guidelines OPPTS 870.2500 Acute Dermal Irritation August 1998

- Japanese Ministry of Agriculture, Forestry and Fisheries (JMAFF), Testing Guidelines for Toxicology Studies, 12 NohSan No. 8147, amended 10 December 2002

- Japanese Ministry of Health and Welfare, 1992

Results. 

3-minute and 1-hour semi-occluded applications of the test item to the intact skin of one rabbit produced no corrosive effects.

A single 4-hour, semi-occluded application of the test item to the intact skin of three rabbits produced very slight to well-defined erythema at two treated skin sites. Very slight oedema, light brown discolouration of the epidermis and loss of skin elasticity were

also noted at one treated skin site. No evidence of skin irritation was noted at one treated skin site during the study. One treated skin site appeared normal at the 48-Hour observation and the remaining treated skin site appeared normal at the 7-Day

observation.

Conclusion. 

The test item produced a primary irritation index of 0.8 and was classified as a mild irritant to rabbit skin according to the Draize classification scheme.

The test item produced a maximum individual mean score of 1.7 and therefore did not meet the criteria for classification according to the Globally Harmonised System of Classification and Labelling of Chemicals.

Reference 3

Endpoint:

skin irritation: in vivo

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Remarks:

sodium sulphamidate

Adequacy of study:

weight of evidence

Justification for type of information:

1. HYPOTHESIS FOR THE ANALOGUE APPROACH
A read across, based on analogue approach, has been performed between ammonium sulphamidate EC 231-871-7 (target chemical) and sodium sulphamidate EC 237-572-8 (source chemical).
The read-across hypothesis, according to Read Across Assessment Framework published by ECHA, is based on the fact that different compounds which have the same type of effect(s). It corresponds to the scenario 2 described as follows:
« This scenario covers the analogue approach for which the read-across hypothesis is based on different compounds which have the same type of effect(s). For the REACH information requirement under consideration, the effects obtained in a study conducted with one source substance are used to predict the effects that would be observed in a study with the target substance if it were to be conducted. The same type of effect(s) or absence of effect is predicted. The predicted strength of the effects may be similar or based on a worst case assumption. »

1) Chemical structure
The target and source substances share the same anionic structure, i.e. a sulphamidate (formula: –OSO2NH2). They only differ by the positive counter ion: an ammonium ion (NH4+) for the target substance and a sodium ion (Na+) for the source substance. It is well known that usually, the counter ion has no impact on the toxicity profile of the substance. For this reason, the QSARs are classically performed on the “core” of the salt and do not consider the counter ion.
See the structures in attached justification.

2) Kinetics
Ammonium sulphamidate
The substance is highly water soluble, meaning its ions dissolve in water. Following oral administration of ammonium sulfamate to dogs for 5 days, 80 to 84% of the dose was excreted as sulfamic acid in the urine, indicating that ammonium sulfamate is readily absorbed into the bloodstream from the gastrointestinal tract. (Pesticide Active Ingredient Information – EXTOXNET)

Sodium sulphamidate
Absorption of sodium sulphamidate from the gastrointestinal tract is supported by the repeated dose reproductive screening study in rats. The high water solubility and small molecular size of sodium sulphamidate allow absorption through passive diffusion. This would suggest that the gastro-intestinal tract provides a route of absorption, following oral administration, before entering the circulatory system via the blood.
Absorption of sodium sulphamidate may also take place via the skin due to small molecular size and water solubility. Although the substance is not a skin sensitizer there is evidence of mild dermal irritation. Therefore damage to the skin surface may allow for increased penetration of the substance through the skin.

Once absorbed, the substance would be distributed in the serum due to the water solubility.

The results of the repeated dose reproductive screening study would suggest that the most likely route of excretion is the kidney due to the likely systemic distribution and water solubility of the test item. Any test item that is not absorbed will be excreted in the faeces. [ECHA’s registration dossier of sodium sulphamidate].

Conclusion
Both substances are absorbed via oral route and are found excreted in urine. Inhalation exposure is not relevant due to the low vapour pressure of each substance.

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
1) Physical and chemical information
The physico-chemical properties were compared between the target and the source substance. Synthron data are in blue and Nalco data (found in ECHA’s registration dossier of sodium sulphamidate) are in green. Published data are in purple and other data are in black (please refer to the comparative table in attached justification).

Both substances share some common physico-chemical properties: white solid appearance, decomposition, high partition coefficient, negligible vapour pressure, absence of surface activity, good water solubility, absence of flammability/explosive and oxidizing properties.
Some physico-chemical differences can be highlighted between the two substances: the different molecular weight is attributed to the counter-ion. The boiling and melting points are slightly different as well as the relative density. The dissociation constants vary due to the different counter-ions which cannot be used for the read-across proposal. In this case, the sulphamidic acid is the most appropriate substance. The pKa values around 1.0 (0.9 or 0.997 or 1.05 as found in the "Handbook of Chemistry and Physics", 85th ed.) all refer to the free acid, sulphamidic acid. Ammonium sulphamate contains as cation the ammonium ion with a pKa of 9.25 ("Handbook of Chemistry and Physics", 85th ed.) Any attempt of coming into the region of pH that is near the pKa of the primary amine group (13.6 ± 0.6) would cause the deprotonation of the ammonium ion and the transformation of the target chemical into the respective alkaline metal salt, for instance sodium sulphamidate. Therefore, the pKa of the primary amine group in the sulphamidate anion reported in the sodium sulphamidate dossier is not relevant for ammonium sulphamidate.
Therefore, both substances share many common physico-chemical features, and the observed differences can be attributed to the different counter-ion.

2) Toxicological and ecotoxicological information
The ammonium ion of the target substance may contribute to the toxicity of ammonium sulphamidate, compared to sodium sulphamidate. However, as both substances are highly water soluble, their ions dissolve in water. Therefore, the ammonium ion is no more a concern.
Please refer to the comparative table in attached justification.

Regarding the toxicity endpoints, some common points are shared by the two substances: low acute toxicity by oral route, no mutagenicity in bacteria, mild to no skin or eye irritation. Some differences occurred in the systemic toxicity study: in the repeated dose toxicity study, the NOAEL are not the same between sodium (NOAEL = 1000 mg/kg bw/d) and ammonium sulphamidate (NOEL = 214.3 mg/kg bw/d). In the reproductive study, NOEL for ammonium sulphamidate was found to be 25 mg/kg bw/d in the literature whereas the NOAEL for sodium sulphamidate is 1000 mg/kg bw/d. However, these differences must be considered with caution as the experimental protocols differ.

As for the ecotoxicity endpoints, both substances seem not to be toxic to fish, based on their LC50 > 100 mg/L (LC50 of at least 650 mg/L).

Last, the environmental fate data on both substances indicate that they are likely to be adsorbed into the soil. Their half-life differ as sodium sulphamidate is very stable (half-life > 1 year) and ammonium sulphamidate may be less stable (half-life of 14 days, based on a published data).


3) Classification proposal
The sodium sulphamidate is not classified in ECHA’s registration dossier. Based on the read-across approach, ammonium sulphamidate would not be classified either.

3. ANALOGUE APPROACH JUSTIFICATION
Based on the available elements, it can be assumed that ammonium and sodium sulphamidate may have close kinetic profiles, physico-chemical, toxicological and ecotoxicological properties. The read-across approach is therefore relevant.

Reason / purpose for cross-reference:

read-across source

Irritation parameter:

erythema score

Basis:

mean

Remarks:

(Animal 1 - 70542)

Time point:

other: Mean of scores at 24, 48 and 72 hours

Score:

1.7

Max. score:

4

Reversibility:

fully reversible within: 7 days

Remarks on result:

other: Results of 4 hour exposure. Light brown discolouration of the epidermis noted at 48 and 72 hours. Loss of skin elasticity noted at 72 hours.

Irritation parameter:

edema score

Basis:

mean

Remarks:

(Animal 1 - 70542)

Time point:

other: Mean of scores at 24, 48 and 72 hours

Score:

0.7

Max. score:

4

Reversibility:

fully reversible within: 7 days

Remarks on result:

other: Results of 4 hour exposure

Irritation parameter:

erythema score

Basis:

mean

Remarks:

(Animal 2 - 70657)

Time point:

other: Mean scores of 24, 48 and 72 hours

Score:

0.3

Max. score:

4

Reversibility:

fully reversible within: 48 hours

Remarks on result:

other: Results from 4 hour exposure

Irritation parameter:

edema score

Basis:

mean

Remarks:

(Animal 2 - 70657)

Time point:

other: Mean scores of 24, 48 and 72 hours

Score:

0

Max. score:

4

Remarks on result:

other: Results from 4 hour exposure

Irritation parameter:

erythema score

Basis:

mean

Remarks:

(Animal 3 - 70658)

Time point:

other: Mean of scores at 24, 48 and 72 hours

Score:

0

Max. score:

4

Remarks on result:

other: Results from 4 hour exposure

Irritation parameter:

edema score

Basis:

mean

Remarks:

(Animal 3 - 70658)

Time point:

other: Mean of scores at 24, 48 and 72 hours

Score:

0

Max. score:

4

Remarks on result:

other: Results from 4 hour exposure

Interpretation of results:

not classified

Conclusions:

Based on the read-across on sodium sulphamidate, ammonium sulphamidate is expected to be classified as a MILD IRRITANT to rabbit skin according to the Draize classification scheme.
It did not meet the criteria for classification according to the Globally Harmonised System of Classification and Labelling of Chemicals.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Eye irritation

Link to relevant study records

Reference

Reference 1

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes

Specific details on test material used for the study:

The test substance was Basensol GS, which was composed of 100% ammonium sulphamidate

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

Young adult rabbits (3.35-3.81 kg each) were housed in fully air-conditioned rooms. Central air-conditioning guaranteed a range of 20-24°C for temperature and of 30-70% for relative humidity.
Day/night rhythm of 12h/12h. Single housing.
About 250 mL tap water per animal per day and about 130 g diet per animal per day.
Acclimatization for at least 1 week.

Vehicle:

unchanged (no vehicle)

Controls:

yes, concurrent no treatment

Amount / concentration applied:

0.1 mL (single application)

Duration of treatment / exposure:

Single application of test substance, which was not washed out.

Observation period (in vivo):

72 hours

Number of animals or in vitro replicates:

3 animals (one male and two females).

Details on study design:

Weight determination: shortly before application of the test substance.
Route of application: single application to the conjunctival sac of the right eyelid; the substance was not washed out.
Readings: 1h, 24h, 48h and 72h after application.
General observations: a check was made twice each workday and once saturdays, sundays and on public holidays for general observations and for any dead or moribund animals.

Irritation parameter:

cornea opacity score

Basis:

mean

Time point:

24/48/72 h

Score:

ca. 0

Irritation parameter:

iris score

Basis:

mean

Time point:

24/48/72 h

Score:

ca. 0

Irritation parameter:

conjunctivae score

Basis:

mean

Time point:

24/48/72 h

Score:

ca. 0.2

Reversibility:

fully reversible within: 48h

Irritation parameter:

chemosis score

Basis:

mean

Time point:

24/48/72 h

Score:

ca. 0

Interpretation of results:

GHS criteria not met

Conclusions:

Under the test conditions chosen and considering the described findings, Basensol GS does not give indication of an irritant property to the eye.

Reference 2

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

The study was performed between 11 July 2011 and 21 July 2011.

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study conducted to GLP and in compliance with agreed protocols, with no or minor deviations from standard test guidelines and/or minor methodological deficiencies, which do not effect the quality of the relevant results.

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Deviations:

no

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2400 (Acute Eye Irritation)

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: Japanese Ministry of Agriculture, Forestry and Fisheries (JMAFF), Testing Guidelines for Toxicology Studies, 12 NohSan No. 8147, amended 10 December 2002

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: Japanese Ministry of Health and Welfare, 1992

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: Three New Zealand White (Hsdlf:NZW) strain rabbits were supplied by Harlan Laboratories UK Ltd., Leicestershire, UK.
- Age at study initiation: twelve to twenty weeks old
- Weight at study initiation: At the start of the study the animals weighed 2.50 to 3.40 kg
- Housing: The animals were individually housed in suspended cages.
- Diet (e.g. ad libitum): Free access to food (2930 Teklad Global Rabbit diet supplied by Harlan Laboratories UK Ltd., Oxon, UK) was allowed throughout the study.
- Water (e.g. ad libitum): Free access to mains drinking water was allowed throughout the study.
- Acclimation period: At least five days.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 17 to 23°C
- Humidity (%): 30 to 70%
Any occasional deviations from these targets were considered not to have affected the purpose or integrity of the study.
- Air changes (per hr): At least fifteen changes per hour
- Photoperiod (hrs dark / hrs light): Lighting was controlled by a time switch to give twelve hours continuous light (06:00 to 18:00) and twelve hours darkness.

Vehicle:

unchanged (no vehicle)

Controls:

yes, concurrent no treatment

Amount / concentration applied:

TEST MATERIAL
A volume of 0.1 ml of the test item, which was found to weigh approximately 73 mg (as measured by gently compacting the required volume into an adapted syringe) was placed into the conjunctival sac of the right eye.

Duration of treatment / exposure:

SIngle application for 72 hour exposure.

Observation period (in vivo):

72 hours

Number of animals or in vitro replicates:

3

Details on study design:

MEASUREMENT OF PH:
The pH of the test item was determined prior to commencement of the study and found to be as follows:
10% w/w aqueous preparation of the test item: pH 8.1 (immediately)
: pH 8.5 (after 10 minutes)

PROCEDURE:
Immediately before the start of the test, both eyes of the provisionally selected test rabbits were examined for evidence of ocular irritation or defect with the aid of a light source from a standard ophthalmoscope. Only animals free of ocular damage were used.

Initially, a single rabbit was treated. A volume of 0.1 ml of the test item, which was found to weigh approximately 73 mg (as measured by gently compacting the required volume into an adapted syringe) was placed into the conjunctival sac of the right eye, formed by gently pulling the lower lid away from the eyeball. The upper and lower eyelids were held together for about one second immediately after treatment, to prevent loss of the test item, and then released. The left eye remained untreated and was used for control purposes. Immediately after administration of the test item, an assessment of the initial pain reaction was made according to the six point scale shown in Appendix 1 (see attached background material).

After consideration of the ocular responses produced in the first treated animal, two additional animals were treated.


SCORING SYSTEM:
Assessment of ocular damage/irritation was made approximately 1 hour and 24, 48 and 72 hours following treatment, according to the numerical Draize Scale for Scoring Ocular Irritation (see Appendix 2 - attached background material).

Any other ocular effects were also noted.

TOOL USED TO ASSESS SCORE: Examination of the eye was facilitated by the use of the light source from a standard ophthalmoscope.

Other:
Any clinical signs of toxicity, if present, were also recorded.

Individual bodyweights were recorded on Day 0 (the day of dosing) and at the end of the observation period.

Irritation parameter:

cornea opacity score

Basis:

mean

Remarks:

(Animal 1 - 70680)

Time point:

other: Mean of scores at 24, 48 and 72 hours

Score:

0

Max. score:

4

Irritation parameter:

cornea opacity score

Basis:

mean

Remarks:

(Animal 2 - 70735)

Time point:

other: Mean of scores at 24, 48 and 72 hours

Score:

0

Max. score:

4

Irritation parameter:

cornea opacity score

Basis:

mean

Remarks:

(Animal 3 - 70735)

Time point:

other: Mean of scores at 24, 48 and 72 hours

Score:

0

Max. score:

4

Irritation parameter:

iris score

Basis:

mean

Remarks:

(Animal 1 - 70680)

Time point:

other: Mean of scores at 24, 48 and 72 hours

Score:

0

Max. score:

2

Irritation parameter:

iris score

Basis:

mean

Remarks:

(Animal 2 - 70734)

Time point:

other: Mean of scores at 24, 48 and 72 hours

Score:

0

Max. score:

2

Irritation parameter:

iris score

Basis:

mean

Remarks:

(Animal 3 - 70735)

Time point:

other: Mean of scores at 24, 48 and 72 hours

Score:

0

Max. score:

2

Irritation parameter:

conjunctivae score

Remarks:

(redness)

Basis:

mean

Remarks:

(Animal 1 - 70680)

Time point:

other: Mean of scores at 24, 48 and 72 hours

Score:

0.67

Max. score:

3

Reversibility:

fully reversible within: 72 hours

Irritation parameter:

conjunctivae score

Remarks:

(redness)

Basis:

mean

Remarks:

(Animal 2 - 70734)

Time point:

other: Mean of scores at 24, 48 and 72 hours

Score:

0.67

Max. score:

3

Reversibility:

fully reversible within: 72 hours

Irritation parameter:

conjunctivae score

Remarks:

(redness)

Basis:

mean

Remarks:

(Animal 3 - 70735)

Time point:

other: Mean of scores at 24, 48 and 72 hours

Score:

0.67

Max. score:

3

Reversibility:

fully reversible within: 72 hours

Irritation parameter:

chemosis score

Basis:

mean

Remarks:

(Animal 1 - 70680)

Time point:

other: Mean of scores at 24, 48 and 72 hours

Score:

0.67

Max. score:

4

Reversibility:

fully reversible within: 72 hours

Irritation parameter:

chemosis score

Basis:

mean

Remarks:

(Animal 2 - 70734)

Time point:

other: Mean of scores at 24, 48 and 72 hours

Score:

0.67

Max. score:

4

Reversibility:

fully reversible within: 72 hours

Irritation parameter:

chemosis score

Basis:

mean

Remarks:

(Animal 3 - 70735)

Time point:

other: Mean of scores at 24, 48 and 72 hours

Score:

0.67

Max. score:

4

Reversibility:

fully reversible within: 72 hours

Irritant / corrosive response data:

Ocular Reactions:
Individual and group mean scores for ocular irritation are given in Table 1 and Table 2.

No corneal or iridial effects were noted during the study.

Moderate conjunctival irritation was noted in all treated eyes one hour after treatment with minimal conjunctival irritation noted at the 24 and 48-Hour observations.

All treated eyes appeared normal at the 72-Hour observation.

Other effects:

Individual bodyweights and bodyweight changes are given in Table 3.
Bodyweight loss was noted in one animal. Two animals showed expected gain in bodyweight during the study.

Table 1              Individual Scores and Individual Total Scoresfor Ocular Irritation

Rabbit Number and Sex	70680 Male				70734Male				70735Male
	IPR= 2				IPR = 2				IPR = 2
Time After Treatment	1 Hour	24 Hours	48 Hours	72 Hours	1 Hour	24 Hours	48 Hours	72 Hours	1 Hour	24 Hours	48 Hours	72 Hours
CORNEA
E = Degree of Opacity	0	0	0	0	0	0	0	0	0	0	0	0
F = Area of Cornea Involved	0	0	0	0	0	0	0	0	0	0	0	0
Score (E x F) x 5	0	0	0	0	0	0	0	0	0	0	0	0
IRIS
D	0	0	0	0	0	0	0	0	0	0	0	0
Score (D x 5)	0	0	0	0	0	0	0	0	0	0	0	0
CONJUNCTIVAE
A = Redness	2	1	1	0	2	1	1	0	2	1	1	0
B = Chemosis	2	1	1	0	2	1	1	0	2	1	1	0
C = Discharge	1	0	0	0	1	0	0	0	1	0	0	0
Score (A + B + C) x 2	10	4	4	0	10	4	4	0	10	4	4	0
Total Score	10	4	4	0	10	4	4	0	10	4	4	0

 

IPR=  Initial pain reaction

Table 2              Individual Total Scores and Group Mean Scores for Ocular Irritation

Rabbit Number and Sex	Individual Total Scores At:
	1 Hour	24 Hours	48 Hours	72 Hours
70680 Male	10	4	4	0
70734Male	10	4	4	0
70735Male	10	4	4	0
Group Total	30	12	12	0
Group Mean Score	10.0	4.0	4.0	0.0

Table 3              Individual Bodyweights and Bodyweight Changes

Rabbit Number and Sex	Individual Bodyweight (kg)		Bodyweight Change (kg)
	Day 0	Day 3
70680 Male	3.40	3.28	-0.12
70734Male	2.69	2.80	0.11
70735Male	2.50	2.66	0.16

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

A single application of the test item to the non-irrigated eye of three rabbits produced moderate conjunctival irritation. All treated eyes appeared normal at the 72 Hour observation.
The test item does not meet the criteria for classification according to the Classification, Labelling and Packaging Regulation or the Globally Harmonised Classification System.

Executive summary:

Introduction. 

The study was performed to assess the irritancy potential of the test item to the eye of the New Zealand White rabbit. The method was designed tobe compatible with thefollowing:

- OECD Guidelines for the Testing of Chemicals No. 405 “Acute Eye Irritation/Corrosion” (adopted 24 April 2002)

- Method B5 Acute Toxicity (Eye Irritation) of CommissionRegulation (EC) No. 440/2008

- United States Environmental Protection Agency Health Effects Tesat Guidelines OPPTS 870.2400 Acute Eye Irritation August 1998

- Japanese Ministry of Agriculture, Forestry and Fisheries (JMAFF), Testing Guidelines for Toxicology Studies, 12 NohSan No. 8147, amended 10 December 2002

- Japanese Ministry of Health and Welfare, 1992

Result. 

A single application of the test item to the non-irrigated eye of three rabbits produced moderate conjunctival irritation. All treated eyes appeared normal at the 72‑Hour observation.

Conclusion. 

The test item produced a maximum group mean score of 10.0 and was classified as a mild irritant (Class 4on a 1 to 8 scale) to the rabbit eye according to a modified Kay and Calandra classification system.

The test item does not meet the criteria for classification according to the Classification, Labelling and Packaging Regulation (CLP) or the Globally Harmonised Classification System.

Reference 3

Endpoint:

eye irritation: in vivo

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Remarks:

sodium sulphamidate

Adequacy of study:

weight of evidence

Justification for type of information:

1. HYPOTHESIS FOR THE ANALOGUE APPROACH
A read across, based on analogue approach, has been performed between ammonium sulphamidate EC 231-871-7 (target chemical) and sodium sulphamidate EC 237-572-8 (source chemical).
The read-across hypothesis, according to Read Across Assessment Framework published by ECHA, is based on the fact that different compounds which have the same type of effect(s). It corresponds to the scenario 2 described as follows:
« This scenario covers the analogue approach for which the read-across hypothesis is based on different compounds which have the same type of effect(s). For the REACH information requirement under consideration, the effects obtained in a study conducted with one source substance are used to predict the effects that would be observed in a study with the target substance if it were to be conducted. The same type of effect(s) or absence of effect is predicted. The predicted strength of the effects may be similar or based on a worst case assumption. »

1) Chemical structure
The target and source substances share the same anionic structure, i.e. a sulphamidate (formula: –OSO2NH2). They only differ by the positive counter ion: an ammonium ion (NH4+) for the target substance and a sodium ion (Na+) for the source substance. It is well known that usually, the counter ion has no impact on the toxicity profile of the substance. For this reason, the QSARs are classically performed on the “core” of the salt and do not consider the counter ion.
See the structures in attached justification.

2) Kinetics
Ammonium sulphamidate
The substance is highly water soluble, meaning its ions dissolve in water. Following oral administration of ammonium sulfamate to dogs for 5 days, 80 to 84% of the dose was excreted as sulfamic acid in the urine, indicating that ammonium sulfamate is readily absorbed into the bloodstream from the gastrointestinal tract. (Pesticide Active Ingredient Information – EXTOXNET)

Sodium sulphamidate
Absorption of sodium sulphamidate from the gastrointestinal tract is supported by the repeated dose reproductive screening study in rats. The high water solubility and small molecular size of sodium sulphamidate allow absorption through passive diffusion. This would suggest that the gastro-intestinal tract provides a route of absorption, following oral administration, before entering the circulatory system via the blood.
Absorption of sodium sulphamidate may also take place via the skin due to small molecular size and water solubility. Although the substance is not a skin sensitizer there is evidence of mild dermal irritation. Therefore damage to the skin surface may allow for increased penetration of the substance through the skin.

Once absorbed, the substance would be distributed in the serum due to the water solubility.

The results of the repeated dose reproductive screening study would suggest that the most likely route of excretion is the kidney due to the likely systemic distribution and water solubility of the test item. Any test item that is not absorbed will be excreted in the faeces. [ECHA’s registration dossier of sodium sulphamidate].

Conclusion
Both substances are absorbed via oral route and are found excreted in urine. Inhalation exposure is not relevant due to the low vapour pressure of each substance.

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
1) Physical and chemical information
The physico-chemical properties were compared between the target and the source substance. Synthron data are in blue and Nalco data (found in ECHA’s registration dossier of sodium sulphamidate) are in green. Published data are in purple and other data are in black (please refer to the comparative table in attached justification).

Both substances share some common physico-chemical properties: white solid appearance, decomposition, high partition coefficient, negligible vapour pressure, absence of surface activity, good water solubility, absence of flammability/explosive and oxidizing properties.
Some physico-chemical differences can be highlighted between the two substances: the different molecular weight is attributed to the counter-ion. The boiling and melting points are slightly different as well as the relative density. The dissociation constants vary due to the different counter-ions which cannot be used for the read-across proposal. In this case, the sulphamidic acid is the most appropriate substance. The pKa values around 1.0 (0.9 or 0.997 or 1.05 as found in the "Handbook of Chemistry and Physics", 85th ed.) all refer to the free acid, sulphamidic acid. Ammonium sulphamate contains as cation the ammonium ion with a pKa of 9.25 ("Handbook of Chemistry and Physics", 85th ed.) Any attempt of coming into the region of pH that is near the pKa of the primary amine group (13.6 ± 0.6) would cause the deprotonation of the ammonium ion and the transformation of the target chemical into the respective alkaline metal salt, for instance sodium sulphamidate. Therefore, the pKa of the primary amine group in the sulphamidate anion reported in the sodium sulphamidate dossier is not relevant for ammonium sulphamidate.
Therefore, both substances share many common physico-chemical features, and the observed differences can be attributed to the different counter-ion.

2) Toxicological and ecotoxicological information
The ammonium ion of the target substance may contribute to the toxicity of ammonium sulphamidate, compared to sodium sulphamidate. However, as both substances are highly water soluble, their ions dissolve in water. Therefore, the ammonium ion is no more a concern.
Please refer to the comparative table in attached justification.

Regarding the toxicity endpoints, some common points are shared by the two substances: low acute toxicity by oral route, no mutagenicity in bacteria, mild to no skin or eye irritation. Some differences occurred in the systemic toxicity study: in the repeated dose toxicity study, the NOAEL are not the same between sodium (NOAEL = 1000 mg/kg bw/d) and ammonium sulphamidate (NOEL = 214.3 mg/kg bw/d). In the reproductive study, NOEL for ammonium sulphamidate was found to be 25 mg/kg bw/d in the literature whereas the NOAEL for sodium sulphamidate is 1000 mg/kg bw/d. However, these differences must be considered with caution as the experimental protocols differ.

As for the ecotoxicity endpoints, both substances seem not to be toxic to fish, based on their LC50 > 100 mg/L (LC50 of at least 650 mg/L).

Last, the environmental fate data on both substances indicate that they are likely to be adsorbed into the soil. Their half-life differ as sodium sulphamidate is very stable (half-life > 1 year) and ammonium sulphamidate may be less stable (half-life of 14 days, based on a published data).


3) Classification proposal
The sodium sulphamidate is not classified in ECHA’s registration dossier. Based on the read-across approach, ammonium sulphamidate would not be classified either.

3. ANALOGUE APPROACH JUSTIFICATION
Based on the available elements, it can be assumed that ammonium and sodium sulphamidate may have close kinetic profiles, physico-chemical, toxicological and ecotoxicological properties. The read-across approach is therefore relevant.

Reason / purpose for cross-reference:

read-across source

Irritation parameter:

cornea opacity score

Basis:

mean

Remarks:

(Animal 1 - 70680)

Time point:

other: Mean of scores at 24, 48 and 72 hours

Score:

0

Max. score:

4

Irritation parameter:

cornea opacity score

Basis:

mean

Remarks:

(Animal 2 - 70735)

Time point:

other: Mean of scores at 24, 48 and 72 hours

Score:

0

Max. score:

4

Irritation parameter:

cornea opacity score

Basis:

mean

Remarks:

(Animal 3 - 70735)

Time point:

other: Mean of scores at 24, 48 and 72 hours

Score:

0

Max. score:

4

Irritation parameter:

iris score

Basis:

mean

Remarks:

(Animal 1 - 70680)

Time point:

other: Mean of scores at 24, 48 and 72 hours

Score:

0

Max. score:

2

Irritation parameter:

iris score

Basis:

mean

Remarks:

(Animal 2 - 70734)

Time point:

other: Mean of scores at 24, 48 and 72 hours

Score:

0

Max. score:

2

Irritation parameter:

iris score

Basis:

mean

Remarks:

(Animal 3 - 70735)

Time point:

other: Mean of scores at 24, 48 and 72 hours

Score:

0

Max. score:

2

Irritation parameter:

conjunctivae score

Remarks:

(redness)

Basis:

mean

Remarks:

(Animal 1 - 70680)

Time point:

other: Mean of scores at 24, 48 and 72 hours

Score:

0.67

Max. score:

3

Reversibility:

fully reversible within: 72 hours

Irritation parameter:

conjunctivae score

Remarks:

(redness)

Basis:

mean

Remarks:

(Animal 2 - 70734)

Time point:

other: Mean of scores at 24, 48 and 72 hours

Score:

0.67

Max. score:

3

Reversibility:

fully reversible within: 72 hours

Irritation parameter:

conjunctivae score

Remarks:

(redness)

Basis:

mean

Remarks:

(Animal 3 - 70735)

Time point:

other: Mean of scores at 24, 48 and 72 hours

Score:

0.67

Max. score:

3

Reversibility:

fully reversible within: 72 hours

Irritation parameter:

chemosis score

Basis:

mean

Remarks:

(Animal 1 - 70680)

Time point:

other: Mean of scores at 24, 48 and 72 hours

Score:

0.67

Max. score:

4

Reversibility:

fully reversible within: 72 hours

Irritation parameter:

chemosis score

Basis:

mean

Remarks:

(Animal 2 - 70734)

Time point:

other: Mean of scores at 24, 48 and 72 hours

Score:

0.67

Max. score:

4

Reversibility:

fully reversible within: 72 hours

Irritation parameter:

chemosis score

Basis:

mean

Remarks:

(Animal 3 - 70735)

Time point:

other: Mean of scores at 24, 48 and 72 hours

Score:

0.67

Max. score:

4

Reversibility:

fully reversible within: 72 hours

Interpretation of results:

not classified

Conclusions:

Based on the read-across on sodium sulphamidate, ammonium sulphamidate does not meet the criteria for classification according to the Classification, Labelling and Packaging Regulation or the Globally Harmonised Classification System.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Justification for classification or non-classification

The results from skin irritation and eye irritation studies were evaluated according to the Classification, Labelling and Packaging Regulation (CLP).

Skin irritation: 

Based on the results, the test item does not meet the criteria for classification according to the Classification, Labelling and Packaging Regulation (CLP).

Eye irritation:

Based on the results, the test item does not meet the criteria for classification according to the Classification, Labelling and Packaging Regulation (CLP)