Registration Dossier

Administrative data

Description of key information

Acute oral toxicity: 

Acute oral toxicity dose was predicted based on OECD QSAR toolbox 3218 mg/kg bw, Danish (Q) SAR Database 2300 mg/kg bw and studies available on structurally similar read across substance Chroman-4-one (CAS no: 491-37-2) 2647 mg/kg bw and closely related read across substance Benzoyl chloride (98-88-4) 2528 mg/kg bw. All these studies concluded that the LD50 value isgreater than 2000 mg/kg bw. Thus, comparing this value with the criteria of CLP regulation, 2-ethoxynaphthalene-1-carbonyl chloride can be classified as category V of acute oral toxicity.

Acute Dermal toxicity: 

Acute Dermal toxicity dose was predicted based on OECD QSAR toolbox 7211 mg/kg bw,and studies available on closely related read across substance Diethylbenzene (25340-17-4) ≥ 5000 mg/kg bw and Naphtha (petroleum), catalytic reformed (68955-35-1) > 2000 mg/kg bw. All these studies concluded that the LD50 value isgreater than 2000 mg/kg bw. Thus, comparing this value with the criteria of CLP regulation, 2-ethoxynaphthalene-1-carbonyl chloride can be classified as category V of acute dermal toxicity.

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records
Reference
Endpoint:
acute toxicity: oral
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 predicted using OECD QSAR toolbox version 3.3 and the supporting QMRF report has been attached
Reference:
Composition 0
Qualifier:
according to
Guideline:
other: estimated
Principles of method if other than guideline:
Prediction is done using QSAR Toolbox version 3.3
GLP compliance:
not specified
Test type:
other: not specified
Limit test:
no
Test material information:
Composition 1
Specific details on test material used for the study:
- IUPAC Name: 2-ethoxynaphthalene-1-carbonyl chloride
- Mol. formula: C13H11ClO2
- Molecular Weight: 234.681 g/mole
- Smiles: O=C(c1c2c(cccc2)ccc1OCC)Cl
- InChI: 1S/C13H11ClO2/c1-2-16-11-8-7-9-5-3-4-6-10(9)12(11)13(14)15/h3-8H,2H2,1H3
Species:
rat
Strain:
Wistar
Sex:
male/female
Details on test animals and environmental conditions:
not specified
Route of administration:
oral: gavage
Vehicle:
not specified
Details on oral exposure:
not specified
Doses:
3218 mg/kg
No. of animals per sex per dose:
not specified
Control animals:
not specified
Details on study design:
not specified
Statistics:
not specified
Preliminary study:
not specified
Sex:
male/female
Dose descriptor:
LD50
Effect level:
3 218 mg/kg bw
Based on:
test mat.
Remarks on result:
other: 50% mortality was observed
Mortality:
not specified
Clinical signs:
not specified
Body weight:
not specified
Gross pathology:
not specified
Other findings:
not specified

The prediction was based on dataset comprised from the following descriptors: LD50
Estimation method: Takes average value from the 6 nearest neighbours
Domain  logical expression:Result: In Domain

((((((("a" or "b" or "c" or "d" )  and ("e" and ( not "f") )  )  and ("g" and ( not "h") )  )  and "i" )  and "j" )  and ("k" and ( not "l") )  )  and ("m" and "n" )  )

Domain logical expression index: "a"

Referential boundary: The target chemical should be classified as Acyl chloride OR Acyl halide OR Alkylarylether OR Aromatic compound OR Carbonic acid derivative OR Carboxylic acid derivative OR Ether OR Halogen derivative by Organic functional groups, Norbert Haider (checkmol) ONLY

Domain logical expression index: "b"

Referential boundary: The target chemical should be classified as Aliphatic Carbon [CH] OR Aliphatic Carbon [-CH2-] OR Aliphatic Carbon [-CH3] OR Aromatic Carbon [C] OR Carbonyl, olefinic attach [-C(=O)-] OR Carbonyl, one aromatic attach [-C(=O)-] OR Chlorine, olefinic attach [-Cl] OR Miscellaneous sulfide (=S) or oxide (=O) OR Olefinic carbon [=CH- or =C<] OR Oxygen, one aromatic attach [-O-] by Organic functional groups (US EPA) ONLY

Domain logical expression index: "c"

Referential boundary: The target chemical should be classified as Aliphatic Carbon [CH] OR Aliphatic Carbon [-CH2-] OR Aliphatic Carbon [-CH3] OR Aromatic Carbon [C] OR Carbonyl, olefinic attach [-C(=O)-] OR Carbonyl, one aromatic attach [-C(=O)-] OR Chlorine, olefinic attach [-Cl] OR Miscellaneous sulfide (=S) or oxide (=O) OR Olefinic carbon [=CH- or =C<] OR Oxygen, one aromatic attach [-O-] by Organic functional groups (US EPA) ONLY

Domain logical expression index: "d"

Referential boundary: The target chemical should be classified as Acyl halide OR Alkoxy OR Aryl OR Ether OR Fused carbocyclic aromatic OR Naphtalene by Organic Functional groups ONLY

Domain logical expression index: "e"

Referential boundary: The target chemical should be classified as SN2 AND SN2 >> Direct acylation involving a leaving group AND SN2 >> Direct acylation involving a leaving group >> Acyl Halides by DNA binding by OASIS v.1.3

Domain logical expression index: "f"

Referential boundary: The target chemical should be classified as AN2 OR AN2 >>  Michael-type addition, quinoid structures OR AN2 >>  Michael-type addition, quinoid structures >> Quinones OR AN2 >> Nucleophilic addition to alpha, beta-unsaturated carbonyl compounds OR AN2 >> Nucleophilic addition to alpha, beta-unsaturated carbonyl compounds >> alpha, beta-Unsaturated Aldehydes OR AN2 >> Schiff base formation OR AN2 >> Schiff base formation >> alpha, beta-Unsaturated Aldehydes OR AN2 >> Schiff base formation >> Polarized Haloalkene Derivatives OR AN2 >> Shiff base formation after aldehyde release OR AN2 >> Shiff base formation after aldehyde release >> Specific Acetate Esters OR AN2 >> Thioacylation via nucleophilic addition after cysteine-mediated thioketene formation OR AN2 >> Thioacylation via nucleophilic addition after cysteine-mediated thioketene formation >> Haloalkenes with Electron-Withdrawing Groups OR AN2 >> Thioacylation via nucleophilic addition after cysteine-mediated thioketene formation >> Polarized Haloalkene Derivatives OR Michael addition OR Michael addition >> Quinone type compounds OR Michael addition >> Quinone type compounds >> Quinone methides OR No alert found OR Non-covalent interaction OR Non-covalent interaction >> DNA intercalation OR Non-covalent interaction >> DNA intercalation >> Quinones OR Radical OR Radical >> Generation of reactive oxygen species OR Radical >> Generation of reactive oxygen species >> Thiols OR Radical >> Radical mechanism by ROS formation (indirect) or direct radical attack on DNA OR Radical >> Radical mechanism by ROS formation (indirect) or direct radical attack on DNA >> Organic Peroxy Compounds OR Radical >> Radical mechanism via ROS formation (indirect) OR Radical >> Radical mechanism via ROS formation (indirect) >> Quinones OR Radical >> ROS formation after GSH depletion OR Radical >> ROS formation after GSH depletion >> Quinone methides OR SN1 OR SN1 >> Alkylation after metabolically formed carbenium ion species OR SN1 >> Alkylation after metabolically formed carbenium ion species >> Polycyclic Aromatic Hydrocarbon Derivatives OR SN1 >> Nucleophilic attack after carbenium ion formation OR SN1 >> Nucleophilic attack after carbenium ion formation >> Specific Acetate Esters OR SN2 >> Acylation OR SN2 >> Acylation >> Specific Acetate Esters OR SN2 >> Alkylation, direct acting epoxides and related OR SN2 >> Alkylation, direct acting epoxides and related >> Epoxides and Aziridines OR SN2 >> Alkylation, direct acting epoxides and related after P450-mediated metabolic activation OR SN2 >> Alkylation, direct acting epoxides and related after P450-mediated metabolic activation >> Haloalkenes with Electron-Withdrawing Groups OR SN2 >> Alkylation, direct acting epoxides and related after P450-mediated metabolic activation >> Polycyclic Aromatic Hydrocarbon Derivatives OR SN2 >> Nucleophilic substitution at sp3 Carbon atom OR SN2 >> Nucleophilic substitution at sp3 Carbon atom >> Specific Acetate Esters OR SN2 >> SN2 at sp3 and activated sp2 carbon atom OR SN2 >> SN2 at sp3 and activated sp2 carbon atom >> Polarized Haloalkene Derivatives by DNA binding by OASIS v.1.3

Domain logical expression index: "g"

Referential boundary: The target chemical should be classified as Not possible to classify according to these rules by DPRA Lysine peptide depletion

Domain logical expression index: "h"

Referential boundary: The target chemical should be classified as Low reactive OR Low reactive >> Acyl halides by DPRA Lysine peptide depletion

Domain logical expression index: "i"

Referential boundary: The target chemical should be classified as Class 3 (unspecific reactivity) by Acute aquatic toxicity classification by Verhaar (Modified) ONLY

Domain logical expression index: "j"

Referential boundary: The target chemical should be classified as Acyl halide AND Alkoxy AND Aryl AND Ether AND Fused carbocyclic aromatic AND Naphtalene by Organic Functional groups ONLY

Domain logical expression index: "k"

Referential boundary: The target chemical should be classified as Not categorized by Repeated dose (HESS)

Domain logical expression index: "l"

Referential boundary: The target chemical should be classified as Valproic acid (Hepatotoxicity) Alert by Repeated dose (HESS)

Domain logical expression index: "m"

Parametric boundary:The target chemical should have a value of log Kow which is >= 0.0156

Domain logical expression index: "n"

Parametric boundary:The target chemical should have a value of log Kow which is <= 4.44

Interpretation of results:
Category 5 based on GHS criteria
Conclusions:
LD50 was estimated to be 3218 mg/kg bw when male and female Wistar rats were treated with 2-ethoxynaphthalene-1-carbonyl chloride via oral gavage route.
Executive summary:

In a prediction done by SSS (2017) using the OECD QSAR toolbox with log kow as the primary descriptor, the acute oral toxicity was estimated for  2-ethoxynaphthalene-1-carbonyl chloride ( 55150-29-3). The LD50 was estimated to be 3218 mg/kg bw when male and female Wistar rats were treated with 2-ethoxynaphthalene-1-carbonyl chloride via oral gavage route.

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
LD50
3 218 mg/kg bw
Quality of whole database:
Data is Klimicsh 2 and from QSAR toolbox 3.3

Acute toxicity: via inhalation route

Endpoint conclusion
Endpoint conclusion:
no study available

Acute toxicity: via dermal route

Link to relevant study records
Reference
Endpoint:
acute toxicity: dermal
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 predicted using OECD QSAR toolbox version 3.3 and the supporting QMRF report has been attached
Reference:
Composition 0
Qualifier:
according to
Guideline:
other: estimated
Principles of method if other than guideline:
Prediction is done using QSAR Toolbox version 3.3
GLP compliance:
not specified
Test type:
other: not specified
Limit test:
no
Test material information:
Composition 1
Specific details on test material used for the study:
- IUPAC Name: 2-ethoxynaphthalene-1-carbonyl chloride
- Mol. formula: C13H11ClO2
- Molecular Weight: 234.681 g/mole
- Smiles: O=C(c1c2c(cccc2)ccc1OCC)Cl
- InChI: 1S/C13H11ClO2/c1-2-16-11-8-7-9-5-3-4-6-10(9)12(11)13(14)15/h3-8H,2H2,1H3
Species:
rabbit
Strain:
New Zealand White
Sex:
male/female
Details on test animals and environmental conditions:
not specified
Type of coverage:
occlusive
Vehicle:
not specified
Details on dermal exposure:
not specified
Duration of exposure:
24 h
Doses:
7211 mg/kg
No. of animals per sex per dose:
not specified
Control animals:
not specified
Details on study design:
not specified
Statistics:
not specified
Preliminary study:
not specified
Sex:
male/female
Dose descriptor:
LD50
Effect level:
7 211 mg/kg bw
Based on:
test mat.
Remarks on result:
other: 50% mortality was observed
Mortality:
not specified
Clinical signs:
not specified
Body weight:
not specified
Gross pathology:
not specified
Other findings:
not specified

The prediction was based on dataset comprised from the following descriptors: LD50
Estimation method: Takes average value from the 6 nearest neighbours
Domain  logical expression:Result: In Domain

(((((((((((("a" or "b" or "c" or "d" )  and ("e" and ( not "f") )  )  and ("g" and ( not "h") )  )  and ("i" and ( not "j") )  )  and ("k" and ( not "l") )  )  and "m" )  and "n" )  and "o" )  and ("p" and ( not "q") )  )  and ("r" and ( not "s") )  )  and ("t" and ( not "u") )  )  and ("v" and "w" )  )

Domain logical expression index: "a"

Referential boundary: The target chemical should be classified as Acyl chloride OR Acyl halide OR Alkylarylether OR Aromatic compound OR Carbonic acid derivative OR Carboxylic acid derivative OR Ether OR Halogen derivative by Organic functional groups, Norbert Haider (checkmol) ONLY

Domain logical expression index: "b"

Referential boundary: The target chemical should be classified as Aliphatic Carbon [CH] OR Aliphatic Carbon [-CH2-] OR Aliphatic Carbon [-CH3] OR Aromatic Carbon [C] OR Carbonyl, olefinic attach [-C(=O)-] OR Carbonyl, one aromatic attach [-C(=O)-] OR Chlorine, olefinic attach [-Cl] OR Miscellaneous sulfide (=S) or oxide (=O) OR Olefinic carbon [=CH- or =C<] OR Oxygen, one aromatic attach [-O-] by Organic functional groups (US EPA) ONLY

Domain logical expression index: "c"

Referential boundary: The target chemical should be classified as Aliphatic Carbon [CH] OR Aliphatic Carbon [-CH2-] OR Aliphatic Carbon [-CH3] OR Aromatic Carbon [C] OR Carbonyl, olefinic attach [-C(=O)-] OR Carbonyl, one aromatic attach [-C(=O)-] OR Chlorine, olefinic attach [-Cl] OR Miscellaneous sulfide (=S) or oxide (=O) OR Olefinic carbon [=CH- or =C<] OR Oxygen, one aromatic attach [-O-] by Organic functional groups (US EPA) ONLY

Domain logical expression index: "d"

Referential boundary: The target chemical should be classified as Acyl halide OR Alkoxy OR Aryl OR Ether OR Fused carbocyclic aromatic OR Naphtalene by Organic Functional groups ONLY

Domain logical expression index: "e"

Referential boundary: The target chemical should be classified as Non binder, without OH or NH2 group by Estrogen Receptor Binding

Domain logical expression index: "f"

Referential boundary: The target chemical should be classified as Non binder, MW>500 OR Non binder, non cyclic structure by Estrogen Receptor Binding

Domain logical expression index: "g"

Referential boundary: The target chemical should be classified as Not possible to classify according to these rules (GSH) by Protein binding potency

Domain logical expression index: "h"

Referential boundary: The target chemical should be classified as Highly reactive (GSH) OR Highly reactive (GSH) >> 2-Alken-1-als (MA) OR Highly reactive (GSH) >> Acrylates (MA) OR Highly reactive (GSH) >> Cinnamaldehydes (MA) OR Moderately reactive (GSH) OR Moderately reactive (GSH) >> 2-Vinylpyridine (MA) OR Moderately reactive (GSH) >> Alkyl 2-alkenoates (MA) OR Moderately reactive (GSH) >> Substituted 1-Alken-3-ones (MA) OR Moderately reactive (GSH) >> Substituted 2-Alken-1-als (MA) OR Slightly reactive (GSH) OR Slightly reactive (GSH) >> 2-Alkenyl carbonitriles (MA) OR Slightly reactive (GSH) >> Methacrylates (MA) by Protein binding potency

Domain logical expression index: "i"

Referential boundary: The target chemical should be classified as Inclusion rules not met by Skin irritation/corrosion Inclusion rules by BfR

Domain logical expression index: "j"

Referential boundary: The target chemical should be classified as Activated N-heterocycles OR Epoxides(=oxiranes) OR Substituted benzoic acid halogenides by Skin irritation/corrosion Inclusion rules by BfR

Domain logical expression index: "k"

Referential boundary: The target chemical should be classified as Group 14 - Carbon C AND Group 16 - Oxygen O AND Group 17 - Halogens Cl AND Group 17 - Halogens F,Cl,Br,I,At by Chemical elements

Domain logical expression index: "l"

Referential boundary: The target chemical should be classified as Group 14 - Metalloids Si,Ge OR Group 15 - Nitrogen N OR Group 15 - Phosphorus P OR Group 16 - Sulfur S by Chemical elements

Domain logical expression index: "m"

Referential boundary: The target chemical should be classified as Bioavailable by Lipinski Rule Oasis ONLY

Domain logical expression index: "n"

Referential boundary: The target chemical should be classified as Aliphatic Carbon [CH] AND Aliphatic Carbon [-CH2-] AND Aliphatic Carbon [-CH3] AND Aromatic Carbon [C] AND Carbonyl, olefinic attach [-C(=O)-] AND Carbonyl, one aromatic attach [-C(=O)-] AND Chlorine, olefinic attach [-Cl] AND Miscellaneous sulfide (=S) or oxide (=O) AND Olefinic carbon [=CH- or =C<] AND Oxygen, one aromatic attach [-O-] by Organic functional groups (US EPA) ONLY

Domain logical expression index: "o"

Referential boundary: The target chemical should be classified as Acyl chloride AND Acyl halide AND Alkylarylether AND Aromatic compound AND Carbonic acid derivative AND Carboxylic acid derivative AND Ether AND Halogen derivative by Organic functional groups, Norbert Haider (checkmol) ONLY

Domain logical expression index: "p"

Referential boundary: The target chemical should be classified as Not categorized by Repeated dose (HESS)

Domain logical expression index: "q"

Referential boundary: The target chemical should be classified as 3-Methylcholantrene (Hepatotoxicity) Alert OR Amineptine (Hepatotoxicity) Alert OR Aromatic hydrocarbons (Liver enzyme induction) Rank C by Repeated dose (HESS)

Domain logical expression index: "r"

Referential boundary: The target chemical should be classified as No alert found by Respiratory sensitisation

Domain logical expression index: "s"

Referential boundary: The target chemical should be classified as SN2 OR SN2 >> Ring opening SN2 OR SN2 >> Ring opening SN2 >>  Epoxides by Respiratory sensitisation

Domain logical expression index: "t"

Referential boundary: The target chemical should be classified as Not known precedent reproductive and developmental toxic potential by DART scheme v.1.0

Domain logical expression index: "u"

Referential boundary: The target chemical should be classified as Known precedent reproductive and developmental toxic potential OR Toluene and small alkyl toluene derivatives (8a) by DART scheme v.1.0

Domain logical expression index: "v"

Parametric boundary:The target chemical should have a value of log Kow which is >= 1.99

Domain logical expression index: "w"

Parametric boundary:The target chemical should have a value of log Kow which is <= 4.07

Interpretation of results:
Category 5 based on GHS criteria
Remarks:
Migrated information
Conclusions:
LD50 was estimated to be 7211 mg/kg bw when New Zealand White male and female rabbits were treated with 2-ethoxynaphthalene-1-carbonyl chloride by dermal application occlusively for 24 h.
Executive summary:

In a prediction done by SSS (2017) using the OECD QSAR toolbox with log kow as the primary descriptor, the acute dermal toxicity was estimated for  2-ethoxynaphthalene-1-carbonyl chloride ( 55150-29-3). The LD50 was estimated to be 7211 mg/kg bw when New Zealand White male and female rabbits were treated with 2-ethoxynaphthalene-1-carbonyl chloride by dermal application occlusively for 24 h.

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
LD50
7 211 mg/kg bw
Quality of whole database:
Data is Klimicsh 2 and from QSAR toolbox 3.3

Additional information

Acute oral toxicity:

In different studies, 2-ethoxynaphthalene-1-carbonyl chloride (55150-29-3) has been investigated for acute oral toxicity to a greater or lesser extent. Often are the studies based on in vivo experiments in rodents, i.e. most commonly in rats for 2-ethoxynaphthalene-1-carbonyl chloride along with the study available on structurally similar read across substance Chroman-4-one (CAS no: 491-37-2) and closely related read across substance Benzoyl chloride (98-88-4). The predicted data using the OECD QSAR toolbox has also been compared with the experimental studies. The studies are summarized as below –

In a prediction done by SSS (2017) using the OECD QSAR toolbox with log kow as the primary descriptor, the acute oral toxicity was estimated for 2-ethoxynaphthalene-1-carbonyl chloride (55150-29-3). The LD50 was estimated to be 3218 mg/kg bw when male and female Wistar rats were treated with 2-ethoxynaphthalene-1-carbonyl chloride via oral gavage route.

In another experimental study based on the QSAR prediction done using the Danish (Q) SAR Database (2017), the acute oral toxicity was estimated for the 2-ethoxynaphthalene-1-carbonyl chloride (55150-29-3). The LD50 was estimated to be 2300 mg/kg bw with Reliability Index 0.81 (>0.75 = high prediction quality), when rats were treated with 2-ethoxynaphthalene-1-carbonyl chloride orally.

The above study supported by U.S. National Library of Medicine, ChemIDplus (2017), for the structurally similar read across substance Chroman-4-one (CAS no: 491-37-2). The acute oral toxicity was tested in rats at the dose concentration of 2647 mg/kg bw. Animals were observed for clinical signs. 50% mortality was observed at 2647 mg/kg with clinical signs such as, ataxia, hyper motility in GIT, diarrhoea and Chromodacyrorrea. Therefore, LD50 was considered to be 2647 mg/kg bw, when rats were treated with Chroman-4-one via oral route.

This is further supported by U. S. Environmental Protection Agency (2012), for the closely related read across substance Benzoyl chloride (98-88-4). The Acute oral toxicity study was conducted in 60 (10/dose) male Wistar rats using undiluted Benzoyl chloride. Doses were given in concentration 1210, 1820, 2420, 3030, 3750 or 6040 mg/kg via oral gavage route and observed for 14 days. Mortality was observed at 1820(2), 2420(5), 3030(6), 3750(9) and 6040(10) mg/kg. 50% mortality was observed at dose 2528mg/kg bw with the signs of intoxication reported as, sedation, extention spasm, reduced general condition in animals were observed. Hence, LD50 was considered to be 2528mg/kg bw, when male Wistar rats were treated with Benzoyl chloride (98-88-4) orally.

Thus, based on the above studies on 2-ethoxynaphthalene-1-carbonyl chloride (55150-29-3) and it’s read across substances, it can be concluded that LD50 value is greater than 2000 mg/kg bw. Thus, comparing this value with the criteria of CLP regulation, 2-ethoxynaphthalene-1-carbonyl chloride can be classified as category V of acute oral toxicity.

Acute Dermal toxicity:

In different studies, 2-ethoxynaphthalene-1-carbonyl chloride (CAS no: 55150-29-3) has been investigated for acute dermal toxicity to a greater or lesser extent. Often are the studies based on in vivo experiments in rodents, i.e. most commonly in rabbits for 2-ethoxynaphthalene-1-carbonyl chloride along with the study available on closely related read across substance Diethylbenzene (25340-17-4) and Naphtha (petroleum), catalytic reformed (68955-35-1). The predicted data using the OECD QSAR toolbox has also been compared with the experimental studies. The studies are summarized as below –

In a prediction done by SSS (2017) using the OECD QSAR toolbox with log kow as the primary descriptor, the acute dermal toxicity was estimated for 2-ethoxynaphthalene-1-carbonyl chloride (55150-29-3). The LD50 was estimated to be 7211 mg/kg bw when New Zealand White male and female rabbits were treated with 2-ethoxynaphthalene-1-carbonyl chloride by dermal application occlusively for 24 h.

This is further supported by U. S. Environmental Protection Agency (ROBUST SUMMARIES for the Diethylbenzene, 2004), for the closely related read across substance Diethylbenzene (25340-17-4). The Acute Dermal toxicity study was conducted according to TSCA guideline in 10 Male and Female New Zealand White rabbits at the concentration of 5000 mg/kg bw. At start of the experiment, animals were at least 8 weeks old. The males weighed between 2.3-2.6 kg, and the females weighed between 2.6-2.7 kg. Room temperature was 60-70°F, and relative humidity was between 30-70% during the study. Animals were observed for 14 days post dose. Animals were observed for clinical examination and body weight (loss/gain). FIFRA method was used. No Mortality observed at 5000 mg/kg bw. Fissuring exhibited at a small portion of the dose site, in 1 animal, no severe dermal effect were seen. Decreased food consumption was exhibited by all 10 animals on the day after dosing; by 4 animals on Day 4; and by 1 animal on Day 10. All animals exhibited body weight losses or no weight change at Day 7, but most gained weight between Days 7 and 14. Therefore, LD50 was considered to be ≥ 5000 mg/kg bw, when male and female New Zealand White rabbits were treated with Diethylbenzene (25340-17-4) by dermal application.

The above study supported by National Industrial Chemicals Notification and Assessment Scheme - NICNAS (2017), for the closely related read across substance Naphtha (petroleum), catalytic reformed (68955-35-1). The acute dermal toxicity was tested in New Zealand White rabbits at the concentration of 2000 mg/kg bw. No mortality was observed at 2000 mg/kg bw. Therefore, the LD50 was considered to be > 2000 mg/kg bw, when New Zealand White rabbits were treated with Naphtha (petroleum), catalytic reformed (68955-35-1) by dermal application.

Thus, based on the above studies on 2-ethoxynaphthalene-1-carbonyl chloride (55150-29-3) and it’s read across substances, it can be concluded that LD50 value is greater than 2000 mg/kg bw. Thus, comparing this value with the criteria of CLP regulation, 2-ethoxynaphthalene-1-carbonyl chloride can be classified as category V of acute dermal toxicity.

Justification for classification or non-classification

Based on the above studies and prediction on 2-ethoxynaphthalene-1-carbonyl chloride (55150-29-3) and it’s read across substances, it can be concluded that LD50 value is greater than 2000 mg/kg bw. Thus, comparing this value with the criteria of CLP regulation, 2-ethoxynaphthalene-1-carbonyl chloride can be classified as category V for acute oral and dermal toxicity.