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EC number: 208-358-1 | CAS number: 524-38-9
- Life Cycle description
- Uses advised against
- Endpoint summary
- Appearance / physical state / colour
- Melting point / freezing point
- Boiling point
- Density
- Particle size distribution (Granulometry)
- Vapour pressure
- Partition coefficient
- Water solubility
- Solubility in organic solvents / fat solubility
- Surface tension
- Flash point
- Auto flammability
- Flammability
- Explosiveness
- Oxidising properties
- Oxidation reduction potential
- Stability in organic solvents and identity of relevant degradation products
- Storage stability and reactivity towards container material
- Stability: thermal, sunlight, metals
- pH
- Dissociation constant
- Viscosity
- Additional physico-chemical information
- Additional physico-chemical properties of nanomaterials
- Nanomaterial agglomeration / aggregation
- Nanomaterial crystalline phase
- Nanomaterial crystallite and grain size
- Nanomaterial aspect ratio / shape
- Nanomaterial specific surface area
- Nanomaterial Zeta potential
- Nanomaterial surface chemistry
- Nanomaterial dustiness
- Nanomaterial porosity
- Nanomaterial pour density
- Nanomaterial photocatalytic activity
- Nanomaterial radical formation potential
- Nanomaterial catalytic activity
- Endpoint summary
- Stability
- Biodegradation
- Bioaccumulation
- Transport and distribution
- Environmental data
- Additional information on environmental fate and behaviour
- Ecotoxicological Summary
- Aquatic toxicity
- Endpoint summary
- Short-term toxicity to fish
- Long-term toxicity to fish
- Short-term toxicity to aquatic invertebrates
- Long-term toxicity to aquatic invertebrates
- Toxicity to aquatic algae and cyanobacteria
- Toxicity to aquatic plants other than algae
- Toxicity to microorganisms
- Endocrine disrupter testing in aquatic vertebrates – in vivo
- Toxicity to other aquatic organisms
- Sediment toxicity
- Terrestrial toxicity
- Biological effects monitoring
- Biotransformation and kinetics
- Additional ecotoxological information
- Toxicological Summary
- Toxicokinetics, metabolism and distribution
- Acute Toxicity
- Irritation / corrosion
- Sensitisation
- Repeated dose toxicity
- Genetic toxicity
- Carcinogenicity
- Toxicity to reproduction
- Specific investigations
- Exposure related observations in humans
- Toxic effects on livestock and pets
- Additional toxicological data
Endpoint summary
Administrative data
Description of key information
Skin Irritation:
The dermal irritation potential of N-Hydroxyphthalimide was estimated using OECD QSAR toolbox version 3.4 with logPow as the primary descriptor.
N-Hydroxyphthalimide was estimated to be irritating to the skin of albino rabbits.
Based on the estimated result, N-Hydroxyphthalimide can be considered to be irritating to skin and can be classified under the category “Category 2”as per CLP regulation.
Eye Irritation:
The ocular irritation potential of N-Hydroxyphthalimide was estimated using OECD QSAR toolbox version 3.4 with logPow as the primary descriptor.
N-Hydroxyphthalimide was estimated to be irritating to the eyes of New Zealand White rabbits.
Based on the estimated result, N-Hydroxyphthalimide can be considered to be irritating to eyes and can be classified under the category “Category 2”as per CLP regulation.
Key value for chemical safety assessment
Skin irritation / corrosion
Link to relevant study records
- Endpoint:
- skin irritation: in vivo
- Type of information:
- (Q)SAR
- Adequacy of study:
- weight of evidence
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- results derived from a valid (Q)SAR model and falling into its applicability domain, with limited documentation / justification
- Justification for type of information:
- data is from OECD QSAR toolbox v 3.4 and teh QMRF report has been attached
- Qualifier:
- according to guideline
- Guideline:
- other: estimated data
- Principles of method if other than guideline:
- Prediction was done using OECD QSAR toolbox v3.4
- GLP compliance:
- not specified
- Specific details on test material used for the study:
- Substance Name: N-Hydroxyphthalimide
Molecular formula: C8H5NO3
Molecular weight: 163.132 g/mol
Substance Type: Organic
Physical State: Solid - Species:
- rabbit
- Strain:
- other: albino
- Details on test animals or test system and environmental conditions:
- no data available
- Type of coverage:
- semiocclusive
- Preparation of test site:
- shaved
- Vehicle:
- unchanged (no vehicle)
- Controls:
- not specified
- Amount / concentration applied:
- undiluted 0.5g
- Duration of treatment / exposure:
- 5 minutes
- Observation period:
- 24,48,72 hours and 5 days
- Number of animals:
- 6
- Details on study design:
- no data available
- Irritation parameter:
- overall irritation score
- Basis:
- mean
- Time point:
- other: 5 days
- Reversibility:
- not specified
- Remarks on result:
- positive indication of irritation
- Irritant / corrosive response data:
- Irritation was observed
- Interpretation of results:
- Category 2 (irritant) based on GHS criteria
- Conclusions:
- N-Hydroxyphthalimide was estimated to be irritating to the skin of albino rabbits.
- Executive summary:
The skin irritation potential of N-Hydroxyphthalimide was estimated using OECD QSAR toolbox version 3.4 with logPow as the primary descriptor.
N-Hydroxyphthalimide was estimated to be irritating to the skin of albino rabbits.
Based on the estimated result, N-Hydroxyphthalimide can be considered to be irritating to skin and can be classified under the category “Category 2”as per CLP regulation.
Reference
Estimation
method: Takes mode value from the 5 nearest neighbours
Domain logical expression:Result: In Domain
((((((((((((("a"
or "b" or "c" or "d" or "e") and
"f") and("g"
and(not
"h")) ) and("i"
and(not
"j")) ) and
"k") and
"l") and
"m") and("n"
and(not
"o")) ) and("p"
and(not
"q")) ) and("r"
and(not
"s")) ) and
"t") and
"u") and("v"
and "w") )
Domain
logical expression index: "a"
Referential
boundary:The
target chemical should be classified as Imides (Acute toxicity) by
US-EPA New Chemical Categories
Domain
logical expression index: "b"
Referential
boundary:The
target chemical should be classified as Aryl AND Fused saturated
heterocycles AND Hydroxamic acid AND Imide AND N-Hydroxylamine
derivatives by Organic Functional groups
Domain
logical expression index: "c"
Referential
boundary:The
target chemical should be classified as Aryl AND Fused saturated
heterocycles AND Hydroxamic acid AND Imide AND Overlapping groups by
Organic Functional groups (nested)
Domain
logical expression index: "d"
Referential
boundary:The
target chemical should be classified as Amide, aromatic attach [-C(=O)N]
AND Aromatic Carbon [C] AND Carbonyl, olefinic attach [-C(=O)-] AND
Carbonyl, one aromatic attach [-C(=O)-] AND Hydroxy, nitrogen attach
[-OH] AND Miscellaneous sulfide (=S) or oxide (=O) AND Nitrogen, two or
tree olefinic attach [>N-] AND Olefinic carbon [=CH- or =C<] AND Oxygen,
nitrogen attach [-O-] AND Oxygen-subtution at N on [-CO-N-CO-] by
Organic functional groups (US EPA)
Domain
logical expression index: "e"
Referential
boundary:The
target chemical should be classified as Aromatic compound AND Carbonic
acid derivative AND Carboxylic acid derivative AND Heterocyclic compound
by Organic functional groups, Norbert Haider (checkmol)
Domain
logical expression index: "f"
Referential
boundary:The
target chemical should be classified as Bioavailable by Lipinski Rule
Oasis ONLY
Domain
logical expression index: "g"
Referential
boundary:The
target chemical should be classified as Non-Metals by Groups of elements
Domain
logical expression index: "h"
Referential
boundary:The
target chemical should be classified as Halogens by Groups of elements
Domain
logical expression index: "i"
Referential
boundary:The
target chemical should be classified as Group 14 - Carbon C AND Group 15
- Nitrogen N AND Group 16 - Oxygen O by Chemical elements
Domain
logical expression index: "j"
Referential
boundary:The
target chemical should be classified as Group 16 - Sulfur S by Chemical
elements
Domain
logical expression index: "k"
Similarity
boundary:Target:
ON1C(=O)c2ccccc2C1=O
Threshold=40%,
Dice(Atom centered fragments)
Atom type; Count H attached; Hybridization
Domain
logical expression index: "l"
Similarity
boundary:Target:
ON1C(=O)c2ccccc2C1=O
Threshold=60%,
Dice(Atom centered fragments)
Atom type; Count H attached; Hybridization
Domain
logical expression index: "m"
Similarity
boundary:Target:
ON1C(=O)c2ccccc2C1=O
Threshold=80%,
Dice(Atom centered fragments)
Atom type; Count H attached; Hybridization
Domain
logical expression index: "n"
Referential
boundary:The
target chemical should be classified as Stable form by Tautomers unstable
Domain
logical expression index: "o"
Referential
boundary:The
target chemical should be classified as Imine form - 1,3-H shift OR Keto
form (5-membered heteroarenes) - 1,3-H shift by Tautomers unstable
Domain
logical expression index: "p"
Referential
boundary:The
target chemical should be classified as No alert found by Respiratory
sensitisation
Domain
logical expression index: "q"
Referential
boundary:The
target chemical should be classified as Acylation OR Acylation >> Ring
opening acylation at a carbonyl OR Acylation >> Ring opening acylation
at a carbonyl >> Anhydrides OR Pro-Michael Addition OR Pro-Michael
Addition >> Pro-quinone and related OR Pro-Michael Addition >>
Pro-quinone and related >> Phenylenediamines OR SN2 OR SN2 >> Ring
opening SN2 OR SN2 >> Ring opening SN2 >> Epoxides by Respiratory
sensitisation
Domain
logical expression index: "r"
Referential
boundary:The
target chemical should be classified as Inclusion rules not met by Eye
irritation/corrosion Inclusion rules by BfR
Domain
logical expression index: "s"
Referential
boundary:The
target chemical should be classified as Substituted indoles by Eye
irritation/corrosion Inclusion rules by BfR
Domain
logical expression index: "t"
Referential
boundary:The
target chemical should be classified as weeks - months by Biodeg
ultimate (Biowin 3) ONLY
Domain
logical expression index: "u"
Similarity
boundary:Target:
ON1C(=O)c2ccccc2C1=O
Threshold=10%,
Dice(Atom centered fragments)
Atom type; Count H attached; Hybridization
Domain
logical expression index: "v"
Parametric
boundary:The
target chemical should have a value of log Kow which is >= -2.36
Domain
logical expression index: "w"
Parametric
boundary:The
target chemical should have a value of log Kow which is <= 1.96
Endpoint conclusion
- Endpoint conclusion:
- adverse effect observed (irritating)
Eye irritation
Link to relevant study records
- Endpoint:
- eye irritation: in vivo
- Type of information:
- (Q)SAR
- Adequacy of study:
- weight of evidence
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- results derived from a valid (Q)SAR model and falling into its applicability domain, with limited documentation / justification
- Justification for type of information:
- data is from OECD QSAR toolbox v3.4 and the QMRF report has been attached
- Qualifier:
- according to guideline
- Guideline:
- other: estimated data
- Principles of method if other than guideline:
- Prediction was done using OECD QSAR toolbox v3.4
- GLP compliance:
- not specified
- Specific details on test material used for the study:
- Substance Name: N-Hydroxyphthalimide
Molecular formula: C8H5NO3
Molecular weight: 163.132 g/mol
Substance Type: Organic
Physical State: Solid - Species:
- rabbit
- Strain:
- New Zealand White
- Details on test animals or tissues and environmental conditions:
- no data available
- Vehicle:
- unchanged (no vehicle)
- Controls:
- not specified
- Amount / concentration applied:
- 100 mg
- Duration of treatment / exposure:
- single exposure
- Observation period (in vivo):
- 24,48 and 72 hours post instillation
- Duration of post- treatment incubation (in vitro):
- no data available
- Number of animals or in vitro replicates:
- 3
- Irritation parameter:
- overall irritation score
- Basis:
- mean
- Time point:
- 72 h
- Reversibility:
- not specified
- Remarks on result:
- positive indication of irritation
- Irritant / corrosive response data:
- Irritation was observed
- Interpretation of results:
- Category 2 (irritating to eyes) based on GHS criteria
- Conclusions:
- N-Hydroxyphthalimide was estimated to be irritating to the eyes of New Zealand White rabbits.
- Executive summary:
The ocular irritation potential of N-Hydroxyphthalimide was estimated using OECD QSAR toolbox version 3.4 with logPow as the primary descriptor.
N-Hydroxyphthalimide was estimated to be irritating to the eyes of New Zealand White rabbits.
Based on the estimated result, N-Hydroxyphthalimide can be considered to be irritating to eyes and can be classified under the category “Category 2”as per CLP regulation.
Reference
Estimation
method: Takes mode value from the 6 nearest neighbours
Domain logical expression:Result: In Domain
(((((((("a"
or "b" or "c" or "d" or "e") and("f"
and(not
"g")) ) and("h"
and(not
"i")) ) and
"j") and
"k") and
"l") and("m"
and(not
"n")) ) and("o"
and "p") )
Domain
logical expression index: "a"
Referential
boundary:The
target chemical should be classified as Imides (Acute toxicity) by
US-EPA New Chemical Categories
Domain
logical expression index: "b"
Referential
boundary:The
target chemical should be classified as Aryl AND Fused saturated
heterocycles AND Hydroxamic acid AND Imide AND N-Hydroxylamine
derivatives by Organic Functional groups
Domain
logical expression index: "c"
Referential
boundary:The
target chemical should be classified as Aryl AND Fused saturated
heterocycles AND Hydroxamic acid AND Imide AND Overlapping groups by
Organic Functional groups (nested)
Domain
logical expression index: "d"
Referential
boundary:The
target chemical should be classified as Amide, aromatic attach [-C(=O)N]
AND Aromatic Carbon [C] AND Carbonyl, olefinic attach [-C(=O)-] AND
Carbonyl, one aromatic attach [-C(=O)-] AND Hydroxy, nitrogen attach
[-OH] AND Miscellaneous sulfide (=S) or oxide (=O) AND Nitrogen, two or
tree olefinic attach [>N-] AND Olefinic carbon [=CH- or =C<] AND Oxygen,
nitrogen attach [-O-] AND Oxygen-subtution at N on [-CO-N-CO-] by
Organic functional groups (US EPA)
Domain
logical expression index: "e"
Referential
boundary:The
target chemical should be classified as Aromatic compound AND Carbonic
acid derivative AND Carboxylic acid derivative AND Heterocyclic compound
by Organic functional groups, Norbert Haider (checkmol)
Domain
logical expression index: "f"
Referential
boundary:The
target chemical should be classified as No alert found by DNA binding by
OECD
Domain
logical expression index: "g"
Referential
boundary:The
target chemical should be classified as Acylation OR Acylation >> Direct
Addition of an Acyl Halide OR Acylation >> Direct Addition of an Acyl
Halide >> Acyl halide OR Michael addition OR Michael addition >> P450
Mediated Activation of Heterocyclic Ring Systems OR Michael addition >>
P450 Mediated Activation of Heterocyclic Ring Systems >> Furans OR
Michael addition >> P450 Mediated Activation of Heterocyclic Ring
Systems >> Thiophenes-Michael addition OR Michael addition >> P450
Mediated Activation to Quinones and Quinone-type Chemicals OR Michael
addition >> P450 Mediated Activation to Quinones and Quinone-type
Chemicals >> Alkyl phenols OR Michael addition >> P450 Mediated
Activation to Quinones and Quinone-type Chemicals >> Arenes OR SN1 OR
SN1 >> Carbenium Ion Formation OR SN1 >> Carbenium Ion Formation >>
Allyl benzenes OR SN1 >> Iminium Ion Formation OR SN1 >> Iminium Ion
Formation >> Aliphatic tertiary amines OR SN1 >> Nitrenium Ion formation
OR SN1 >> Nitrenium Ion formation >> Aromatic azo OR SN1 >> Nitrenium
Ion formation >> Aromatic nitro OR SN1 >> Nitrenium Ion formation >>
Aromatic phenylureas OR SN1 >> Nitrenium Ion formation >> Primary
(unsaturated) heterocyclic amine OR SN1 >> Nitrenium Ion formation >>
Secondary aromatic amine OR SN1 >> Nitrenium Ion formation >> Tertiary
(unsaturated) heterocyclic amine OR SN1 >> Nitrenium Ion formation >>
Tertiary aromatic amine OR SN1 >> Nitrenium Ion formation >> Unsaturated
heterocyclic azo OR SN2 OR SN2 >> P450 Mediated Epoxidation OR SN2 >>
P450 Mediated Epoxidation >> Thiophenes-SN2 by DNA binding by OECD
Domain
logical expression index: "h"
Referential
boundary:The
target chemical should be classified as Not categorized by Repeated dose
(HESS)
Domain
logical expression index: "i"
Referential
boundary:The
target chemical should be classified as 3-Methylcholantrene
(Hepatotoxicity) Alert OR Benzene/ Naphthalene sulfonic acids (Less
susceptible) Rank C OR Oxyphenistain (Hepatotoxicity) Alert OR Phthalate
esters (Testicular toxicity) Rank C OR Tamoxifen (Hepatotoxicity) Alert
OR Thiocarbamates/Sulfides (Hepatotoxicity) No rank by Repeated dose
(HESS)
Domain
logical expression index: "j"
Referential
boundary:The
target chemical should be classified as Bioavailable by Lipinski Rule
Oasis ONLY
Domain
logical expression index: "k"
Referential
boundary:The
target chemical should be classified as Discrete chemical by Substance
Type ONLY
Domain
logical expression index: "l"
Referential
boundary:The
target chemical should be classified as High (Class III) by Toxic hazard
classification by Cramer (extension) ONLY
Domain
logical expression index: "m"
Referential
boundary:The
target chemical should be classified as No Data by Ultimate biodeg
Domain
logical expression index: "n"
Referential
boundary:The
target chemical should be classified as > 100 days OR 1 to 10 days by
Ultimate biodeg
Domain
logical expression index: "o"
Parametric
boundary:The
target chemical should have a value of log Kow which is >= -0.852
Domain
logical expression index: "p"
Parametric
boundary:The
target chemical should have a value of log Kow which is <= 1.28
Endpoint conclusion
- Endpoint conclusion:
- adverse effect observed (irritating)
Respiratory irritation
Endpoint conclusion
- Endpoint conclusion:
- no study available
Additional information
Skin Irritation:
In different studies, N-Hydroxyphthalimide has been investigated for potential for dermal irritation to a greater or lesser extent. The studies are based on in vivo experiments in rabbits along with predicted data for target chemical and its structurally similar read across substances Potassium Phthalimide (CAS: 1074-82-4) and Phthalimide (CAS: 85-41-6). The predicted data using the OECD QSAR toolbox has also been compared with the experimental data.
In a prediction done by SSS (2017) using the OECD QSAR toolbox with log kow as the primary descriptor, the skin irritation potential was estimated forN-Hydroxyphthalimide. N-Hydroxyphthalimidewas irritating to albino rabbit skin.
This result is supported by the experimental study conducted by Shayne C. Gad et.al (Journal of Toxicology: Cutaneous and Ocular Toxicology; Vol 5(3); Pg. no. 195 -214; 1986)structurally similar read across substance Potassium Phthalimide (CAS: 1074-82-4). 6 New Zealand White rabbits were used for the study.Animals were held for 14 days after arrival in the facility but prior to use in tests to ensure that they are healthy. Each animal served as its own control. Along with the test substance, a positive control substance (a known skin irritant, 1% sodium lauryl sulfate in water) and a negative control (plain gauze patch) are applied to the skin. A vehicle control patch was also used in case the chemical was moistened with a vehicle or suspended in vehicle. Four test sites, two on each side of the rabbit's back, were utilized for administration of test chemical and controls. A standard random pattern of administration ensured that the test substance and controls are applied to each position at least once in each test group. Each test or control substance is held in place with a 1x1 inch2 12-ply surgical gauze patch. The gauze patch is applied to the appropriate skin site and secured with 1-inch wide strips of Blenderm surgical tape, at the four edges, leaving the center of the gauze patch non-occluded. A 0.5-g portion of Potassium Phthalimide was weighed and placed on the gauze patch prior to application of the patch. The test substance and patch are then placed on the appropriate skin site and secured. The patch is subsequently moistened with 0.5 ml physiological saline.The study was on performed on both abraded and non-abraded animals. The negative control site is covered with an untreated 12-ply surgical gauze patch (1X1 inch2). The impervious material (Saran Wrap) aids in maintaining the position of the patches and retards evaporation of volatile test substances. A Saf-T-Shield collar is fitted and fastened around the neck of each test animal. The collar remains in place for a 24 hr exposure period. The collar prevents the animal from removing the wrapping and patches.After the exposure period, the test substance skin site is wiped with dry gauze to remove any test substance still remaining.Dermal irritation scores for erythema and edema formation was evaluated by the scale proposed by Draize.The primary dermal irritation index (PDII) was calculated by dividing the sum of total irritation scores by the number of observations, and classifying the test substance: 0.00 = non-irritant ,>0.00 - 0.50 = negligible irritant, >0.50 -2.00 = mild irritant, >2.00-5.00 = moderate irritant, >5.00-8.00 = severe (primary) irritant. Moderate irritation effect was observed when the rabbits were exposed to the test substance potassium phthalimide for 24 hrs. The Primary Dermal Irritation Index (PDII) for Potassium Phthalimide after 24 hours was 2.3
Based on the scores, Potassium phthalimide can be considered to be moderate skin irritant.
The above results are further supported by the study summarized in SIDS Initial Assessment Report for Phthalimide, 2005, for the structurally similar read across substance Phthalimide (CAS: 85-41-6). The compound was applied to the intact skin of 3 albino male and female rabbits as a 25% suspension in corn oil in 0.5 ml under a one inch by one inch patch, two single layers thick. The patches were held in place with a adhesive tape for 24 hours. Animals were observed for 7 days. The average maximum scores were 1.3 out of possible 8 in twenty-four hours. Hence the test chemical, Phthalimide (CAS No: 85-41-6) was considered as slightly irritating when applied as a 25% suspension in corn oil on albino rabbits.
Based on the available data for the target and read across substances and applying the weight of evidence approach, N-Hydroxyphthalimide can be considered to be not irritating to skin.Comparing the above annotations with the criteria of CLP regulation, it can be classified under the category “Category 2”.
Eye Irritation:
In different studies, N-Hydroxyphthalimide has been investigated for potential for ocular irritation to a greater or lesser extent. The studies are based on in vivo experiments in rabbits along with predicted data for target chemical and its structurally similar read across substances Potassium Phthalimide (CAS: 1074-82-4) and 2 -[(trichloromethyl)sulfanyl]-1H-isoindole-1,3(2H)-dione [Folpet] (CAS: 133-07-3).The predicted data using the OECD QSAR toolbox has also been compared with the experimental data.
In a prediction done by SSS (2017) using the OECD QSAR toolbox with log kow as the primary descriptor, the ocular irritation potential was estimated forN-Hydroxyphthalimide. N-Hydroxyphthalimidewas irritating to New Zealand White rabbit eyes.
This result is supported by the experimental study conducted by Shayne C. Gad et.al (Journal of Toxicology: Cutaneous and Ocular Toxicology; Vol 5(3); Pg. no. 195 -214; 1986)structurally similar read across substance Potassium Phthalimide (CAS: 1074-82-4). 9 New Zealand white rabbits were used for the study. The contralateral eye of each test animal remains untreated and served as a control. 1 hr prior to instillation of the test substance, both eyes of each of at least 12 rabbits were examined for signs of irritation and corneal defects with a handheld slit lamp. Eyes are stained with a 2.0% sodium fluorescein and examined for confirming the absence of corneal lesions. At least 1 hr after fluorescein staining, the test substance is placed on one eye of each animal by gently pulling the lower lid away from the eyeball to form a cup (conjunctival cul-de-sac) into which the test substance is dropped. The upper and lower lids are then held gently together for 1 sec to prevent immediate loss of material. All corneas are examined with the aid of sodium fluorescein. If fluorescein staining appears, diagrams of the staining patterns of the corneal area involved are recorded. If signs of irritation persist at 7 days, reading are continued on day 10. If irritation is still persistent on day 10, then readings are taken on day 14. Most lesions, if reversible, will heal or clear within 21 days. Therefore, if ocular irritation is present at the 14-day reading, a 21-day reading is required to determine whether the ocular damage is reversible or non-reversible. The Federal Hazardous Substances Act (FHSA) Regulations was used to determine whether the test substance was an eye irritant or not. Interpretation of data was made using only the six test eyes not irrigated with water, and only data from days 1, 2, and 3.Grading and scoring of ocular irritation are performed in accordance with the standard Draize grades for ocular lesions.
When the test animals were exposed to the test substance potassium phthalimide, mean Draize score was determined to be 64.0. Based on the mean Draize scores, Potassium phthalimide can be considered to be moderately irritating to New Zealand White rabbit eyes.
The above results are further supported by the study summarized in Draft Assessment Report (DAR) – Folpet, Volume 3, Annex B B.6; Rapporteur Member State: Italy; April 2005, for the structurally similar read across substance, 2-[(trichloromethyl)sulfanyl]-1H-isoindole-1,3(2H)-dione [Folpet] (CAS: 133-07-3).
0.1 mL of the test substance (87 mg), was placed into the conjunctival sac of the right eye of 6 New Zealand White rabbits. The left eye remained untreated and served as control. An assessment of the initial pain reaction was made after treatment of the first animal before further animals were treated. Assessment of ocular damage/irritation was made according to Draize, approximately 1, 24, 48 and 72 hours following treatment. Additional observations were made 7 and 14 days after treatment to assess the reversibility of the ocular effects. Animals with zero scores on Day 7 were not assessed on Day 14. A modified version of the system described by Kay and Calandra was used to classify the ocular irritancy potential of the test substance. Incidences of vascularisation of the cornea were noted at 7 and 14 days in two animals and pale areas, petechial haemorrhage or haemorrhage of the nictitating membrane in three animals. Four animals appeared normal 7 or 14 days after treatment.
Folpet(CAS No: -133-07-3) technical produced a maximum group mean score of 27.3 and thus was considered as a MODERATE IRRITANT to the rabbit eye according to the modified Kay and Calandra classification system.
Hence, Folpet can be considered as moderately irritating to rabbit eyes.
Based on the available data for the target and read across substances and applying the weight of evidence approach, N-Hydroxyphthalimide can be considered to be not irritating to eyes.Comparing the above annotations with the criteria of CLP regulation, it can be classified under the category “Category 2”.
Justification for classification or non-classification
Available studies for N-Hydroxyphthalimide indicate that it is irritating to eyes and skin.
Hence, N-hydroxyphthalimide can be classified under the category “Category 2” for skin and eyes.
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.
Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.