Registration Dossier
Registration Dossier
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EC number: 234-409-2 | CAS number: 12001-85-3
- 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
The registered substance has been subjected to an in vitro Keratinosens assay for skin sensitisation Key Event 2 for REACH registration. The skin sensitisation of the test item was assessed in a KerationSens Assay with procedure based on the OECD TG 442D guideline, in two independent experiments in triplicate. The test item was suspended in the vehicle solvent, dimethyl sulfoxide (DMSO), prior to dilution with test media and the experiment was performed at final test concentrations 400, 200, 100, 50, 25, 13, 6.3, 3.1, 1.6, 0.78, 0.39 and 0.20 µg/mL (final concentration DMSO of 1%). All formulations formed a clear solution, except the 40 mg/mL stock solution which formed a suspension. No droplet formation was observed in the plates. No precipitation was observed at the start and end of the incubation period in the 96-well plates. Alongside the test item, a solvent (negative control) of DMSO and positive control of Ethylene dimethacrylate glycol (EDMG) were tested. For the positive control, a 2-fold dilution series ranging from 0.78 to 25 mM was prepared in DMSO and diluted, so that the final concentration of the positive control ranged from 7.8 to 250 µM (final concentration DMSO of 1%).
The test substance showed toxicity (IC30 values of 124 µg/mL and 74 µg/mL and IC50 values of 146 µg/mL and 82 µg/mL in experiment 1 and 2, respectively). A biologically relevant, dose-related induction of the luciferase activity (EC1.5 values of 32 µg/mL and 22 µg/mL in experiment 1 and 2, respectively) was measured in both experiments. The maximum luciferase activity induction (Imax) was 2.15-fold and 5.10-fold in experiment 1 and 2 respectively. The test item is classified as positive in the KeratinoSens assay since positive results (>1.5-fold induction) were observed at test concentrations < 200 µg/mL with a cell viability of >70% compared to the vehicle control.
Key value for chemical safety assessment
Skin sensitisation
Link to relevant study records
- Endpoint:
- skin sensitisation: in vitro
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Study period:
- 6 April 2018 - 4 May 2018
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- guideline study
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 442D (In Vitro Skin Sensitisation: ARE-Nrf2 Luciferase Test Method)
- Deviations:
- no
- GLP compliance:
- yes
- Type of study:
- other: KeratinoSens Assay
- Justification for non-LLNA method:
- In the interest of sound science and animal welfare, a sequential testing strategy is recommended to minimize the need for in vivo testing. One of the validated in vitro skin sensitization tests is the KeratinoSensTM assay, which is recommended in international guidelines (e.g. OECD 442D).
- Specific details on test material used for the study:
- - Source and lot/batch No. of test material: A036/99 (Supplier batch number: SCC-1709-0300)
- Expiration date of the lot/batch: 31 August 2018
- Storage condition of test material: At room temperature protected from light - Details on the study design:
- - Test system: A transgenic cell line having a stable insertion of the luciferase reporter gene under the control of the ARE-element is used (e.g. the KeratinoSens™ cell line). The KeratinoSens™ cell line was generated by and obtained from Givaudan (Duebendorf, Switserland). Upon receipt, cells are propagated (e.g. 2 to 4 passages) and stored frozen as a homogeneous stock. Cells from this original stock can be propagated up to a maximum passage number from the frozen stock (i.e. 25) and are employed for routine testing using the appropriate maintenance medium.
- Cell sub-culture: Cells were subcultured upon reaching 80-90% confluency. To maintain the integrity of the response, the cells were grown for more than one passage from the frozen stock, and were not cultured for more than 25 passages from the frozen stock (P+25).
- Cell culture, basic medium: Dulbecco’s minimal (DMEM glutamax) supplemented with 9.1% (v/v) heat-inactivated (56°C; 30 min) fetal calf serum.
- Cell culture, maintenance medium: Dulbecco’s minimal (DMEM glutamax) supplemented with 9.1% (v/v) heat-inactivated (56°C; 30 min) fetal calf serum and geneticin (500 µg/mL).
- Cell culture, exposure medium: Dulbecco’s minimal (DMEM glutamax) supplemented with 1% (v/v) heat-inactivated (56°C; 30 min) fetal calf serum.
- Dose formulation: In the main experiments, the test item was suspended in dimethyl sulfoxide (DMSO) at 40 mg/mL. From this stock, 11 spike solutions in DMSO were prepared (2-fold dilution series). The stock and spike solution were diluted 25-fold with exposure medium. These solutions were diluted 4-fold in the assay, resulting in final test concentrations 400, 200, 100, 50, 25, 13, 6.3, 3.1, 1.6, 0.78, 0.39 and 0.20 µg/mL (final concentration DMSO of 1%). All concentrations of the test item were tested in triplicate. Test item concentrations were used within 3 hours after preparation.
- Solution appearance: All formulations formed a clear solution, except at 40 mg/mL where it formed a suspension. No droplet formation was observed in the plates. No precipitation was observed at the start and end of the incubation period in the 96-well plates.
- Environmental conditions: All incubations, were carried out in a controlled environment, in which optimal conditions were a humid atmosphere of 80 - 100% (actual range 70-100%), containing 5.0 ± 0.5% CO2 in air in the dark at 37.0 ± 1.0°C (actual range 35.7 – 36.3°C). Temperature and humidity were continuously monitored throughout the experiment. The CO2 percentage was monitored once on each working day. Temporary deviations from the temperature and humidity occurred due to opening and closing of the incubator door. Based on laboratory historical data these deviations are considered not to affect the study integrity.
- Plating of cells: For testing, cells were 80-90% confluent. One day prior to testing cells were harvested, and distributed into 96-well plates (10,000 cells/well) in basic medium. For each repetition, three replicates were used for the luciferase activity measurements, and one parallel replicate used for the MTT cell viability assay. The cells were incubated overnight in the incubator. The passage number used was P+9 in experiment 1 and P+12 in experiment 2.
- Treatment of cells: The medium was removed and replaced with fresh culture medium (150 μL culture medium containing serum but without Geneticin) to which 50 μL of the 25-fold diluted test chemical and control items were added. Three wells per plate were left empty (no cells and no treatment) to assess background values. The treated plates were covered with foil and then incubated for about 48 hours at 37±1.0°C in the presence of 5% CO2. Initially, experiment 2 did not pass all the acceptability criteria and therefore this part of the study was repeated. In total, 2 valid experiments were performed.
- Luciferase Activity measurement: The Steady-Glo Luciferase Assay Buffer (10 mL) and Steady-Glo Luciferase Assay Substrate (lyophilized) were mixed together. The assay plates were removed from the incubator and the medium is removed. Then 200 µL of the Steady-Glo Luciferase substrate solution (prior to addition 1:1 mixed with exposure medium) was added to each well. The plates were shaken for at least 3 minutes at room temperature. Plates with the cell lysates were placed in the TECAN Infinite® M200 Pro Plate Reader to assess the quantity of luciferase (integration time two seconds).
- Cytotoxicity assessment: Medium was replaced after the 48 hour exposure time with fresh medium containing MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and cells were incubated for 3 - 4 hours at 37°C in the presence of 5% CO2. The MTT medium was then removed and cells were lysed overnight by adding 10% SDS solution to each well. After shaking, the absorption was measured at 570 nm with the TECAN Infinite® M200 Pro Plate Reader.
- Vehicle control: The vehicle control was 1% DMSO in exposure medium. Eighteen wells were tested per plate.
- Blank control: On each plate three blank wells were tested (no cells and no treatment).
- Positive control: Ethylene dimethacrylate glycol
- Parameters: The following parameters are calculated in the KeratinoSensTM test method:
• The maximal average fold induction of luciferase activity (Imax) value observed at any concentration of the tested chemical and positive control
• The EC1.5 value representing the concentration for which induction of luciferase activity is above the 1.5 fold threshold (i.e. 50% enhanced luciferase activity) was obtained
• The IC50 and IC30 concentration values for 50% and 30% reduction of cellular viability - Positive control results:
- - Experiment 1: The positive control Ethylene dimethacrylate glycol caused a dose related induction of the luciferase activity. The Imax was 2.73 and the EC1.5 75 µM.
- Experiment 2: The positive control Ethylene dimethacrylate glycol caused a dose related induction of the luciferase activity. The Imax was 2.49 and the EC1.5 54 µM. - Run / experiment:
- other: 1
- Parameter:
- other: EC1.5 (µg/mL)
- Value:
- 31.5
- Vehicle controls validity:
- valid
- Negative controls validity:
- valid
- Positive controls validity:
- valid
- Run / experiment:
- other: 2
- Parameter:
- other: EC1.5 (µg/mL)
- Value:
- 21.9
- Vehicle controls validity:
- valid
- Negative controls validity:
- valid
- Positive controls validity:
- valid
- Run / experiment:
- other: 1
- Parameter:
- other: Imax
- Value:
- 2.15
- Vehicle controls validity:
- valid
- Negative controls validity:
- valid
- Positive controls validity:
- valid
- Run / experiment:
- other: 2
- Parameter:
- other: Imax
- Value:
- 5.1
- Vehicle controls validity:
- valid
- Negative controls validity:
- valid
- Positive controls validity:
- valid
- Run / experiment:
- other: 1
- Parameter:
- other: IC30 (µg/mL)
- Value:
- 124
- Vehicle controls validity:
- valid
- Negative controls validity:
- valid
- Positive controls validity:
- valid
- Run / experiment:
- other: 2
- Parameter:
- other: IC30 (µg/mL)
- Value:
- 74
- Vehicle controls validity:
- valid
- Negative controls validity:
- valid
- Positive controls validity:
- valid
- Run / experiment:
- other: 1
- Parameter:
- other: IC50 (µg/mL)
- Value:
- 146
- Vehicle controls validity:
- valid
- Negative controls validity:
- valid
- Positive controls validity:
- valid
- Run / experiment:
- other: 2
- Parameter:
- other: IC50 (µg/mL)
- Value:
- 82
- Vehicle controls validity:
- valid
- Negative controls validity:
- valid
- Positive controls validity:
- valid
- Other effects / acceptance of results:
- Experiment 1
• No precipitation was observed at the start and end of the incubation period in the 96-well plates.
• The test substance showed toxicity. The calculated IC30 was 124 µg/mL and the calculated IC50 was 146 µg/mL.
• A dose related luminescence activity induction was observed after treatment with the test substance. The Imax was 2.15 and the EC1.5 was 32 µg/mL.
Experiment 2
• No precipitation was observed at the start and end of the incubation period in the 96-well plates.
• The test substance showed toxicity. The calculated IC30 was 74 µg/mL and the calculated IC50 was 82 µg/mL.
• A dose related luminescence activity induction was observed after treatment with the test substance. The Imax was 5.10 and the EC1.5 was 22 µg/mL.
ACCEPTANCE OF RESULTS:
- Acceptance criteria met for positive control: The luciferase activity induction obtained with the positive control, Ethylene dimethacrylate glycol, was above the threshold of 1.5-fold in at least one concentration (from 7.8 to 250 µM). The EC1.5 of the positive control was between 5 and 125 µM (75 µM and 54 µM in experiment 1 and 2, respectively). A dose response was observed and the induction at 250 µM was higher than 2-fold (2.73-fold and 2.49-fold in experiment 1 and 2, respectively).
- Acceptance criteria met for variability between replicate measurements: The average coefficient of variation of the luminescence reading for the vehicle (negative) control DMSO was below 20% (7.1% and 11% in experiment 1 and 2, respectively). - Interpretation of results:
- Category 1 (skin sensitising) based on GHS criteria
- Conclusions:
- The test item showed toxicity (IC30 values of 124 µg/mL and 74 µg/mL and IC50 values of 146 µg/mL and 82 µg/mL in experiment 1 and 2, respectively). A biologically relevant, dose-related induction of the luciferase activity (EC1.5 values of 32 µg/mL and 22 µg/mL in experiment 1 and 2, respectively) was measured in both experiments. The maximum luciferase activity induction (Imax) was 2.15-fold and 5.10-fold in experiment 1 and 2 respectively. The test item is classified as positive in the KeratinoSensTM assay since positive results (>1.5-fold induction) were observed at test concentrations < 200 µg/mL with a cell viability of >70% compared to the vehicle control. No adverse interference on the study results of the droplets observed in the dose formulation is expected since the test item is classified as positive, and if interference would be present, it would only lead to an under prediction.
- Executive summary:
The skin sensitisation of the test item was assessed in a KerationSens Assay with procedure based on the OECD TG 442D guideline, in two independent experiments in triplicate. The test item was suspended in the vehicle solvent, dimethyl sulfoxide (DMSO), prior to dilution with test media and the experiment was performed at final test concentrations 400, 200, 100, 50, 25, 13, 6.3, 3.1, 1.6, 0.78, 0.39 and 0.20 µg/mL (final concentration DMSO of 1%). All formulations formed a clear solution, except at 40 mg/mL were it formed a suspension. No droplet formation was observed in the plates. No precipitation was observed at the start and end of the incubation period in the 96-well plates. Alongside the test item, a solvent (negative control) of DMSO and positive control of Ethylene dimethacrylate glycol (EDMG) were tested. For the positive control, a 2-fold dilution series ranging from 0.78 to 25 mM was prepared in DMSO and diluted, so that the final concentration of the positive control ranges from 7.8 to 250 µM (final concentration DMSO of 1%).
The test substance showed toxicity (IC30 values of 124 µg/mL and 74 µg/mL and IC50 values of 146 µg/mL and 82 µg/mL in experiment 1 and 2, respectively). A biologically relevant, dose-related induction of the luciferase activity (EC1.5 values of 32 µg/mL and 22 µg/mL in experiment 1 and 2, respectively) was measured in both experiments. The maximum luciferase activity induction (Imax) was 2.15-fold and 5.10-fold in experiment 1 and 2 respectively. The test item is classified as positive in the KeratinoSens assay since positive results (>1.5-fold induction) were observed at test concentrations < 200 µg/mL with a cell viability of >70% compared to the vehicle control.
Reference
Table 1. Overview Luminescence Induction and Cell Viability of the test substance in Experiment 1 and 2
Concentration (µg/mL) |
0.20 |
0.39 |
0.78 |
1.6 |
3.1 |
6.3 |
13 |
25 |
50 |
100 |
200 |
400 |
Exp 1 luminescence |
1.09 |
1.10 |
1.12 |
1.03 |
1.09 |
1.07 |
1.08 |
1.38 |
1.85*** |
2.15 |
0.00 |
0.00 |
Exp 1 viability (%) |
109.3 |
105.8 |
89.3 |
86.1 |
78.8 |
73.7 |
78.1 |
92.8 |
117.1 |
92.3 |
-0.2 |
-0.2 |
Exp 2 luminescence |
1.05 |
1.06 |
0.98 |
0.93 |
1.01 |
1.02 |
1.04 |
1.66*** |
5.10** |
0.00 |
0.00 |
0.00 |
Exp 2 viability (%) |
103.8 |
98.0 |
103.5 |
103.3 |
104.4 |
101.5 |
110.7 |
137.5 |
133.9 |
1.0 |
3.1 |
-0.9 |
**p<0.01 Student’s t test
***p<0.001 Student’s t test
Table 2. Overview Luminescence Induction and Cell Viability Positive Control EDMG in Experiment 1 and 2
Concentration (µM) |
7.8 |
16 |
31 |
63 |
125 |
250 |
Exp 1 luminescence |
1.05 |
1.05 |
1.27 |
1.41 |
1.88*** |
2.73*** |
Exp 1 viability (%) |
100.8 |
104.6 |
103.9 |
109.9 |
110.9 |
106.2 |
Exp 2 luminescence |
1.05 |
1.09 |
1.24 |
1.61*** |
1.80*** |
2.49*** |
Exp 2 viability (%) |
98.9 |
101.2 |
104.8 |
110.8 |
102.6 |
121.5 |
***p<0.001 Student’s t test
Table 3. Overview EC1.5, Imax, IC30 and IC50 Values
|
EC1.5(µg/mL) |
Imax |
IC30(µg/mL) |
IC50(µg/mL) |
Test item Experiment 1 |
31.5 |
2.15 |
124 |
146 |
Test item Experiment 2 |
21.9 |
5.10 |
74 |
82 |
|
EC1.5(µM) |
Imax |
IC30(µM) |
IC50(µM) |
Pos Control Experiment 1 |
74.9 |
2.73 |
NA |
NA |
Pos Control Experiment 2 |
53.5 |
2.49 |
NA |
NA |
NA = Not applicable
Endpoint conclusion
- Endpoint conclusion:
- adverse effect observed (sensitising)
Respiratory sensitisation
Endpoint conclusion
- Endpoint conclusion:
- no study available
- Additional information:
The EC1.5 for zinc naphthenate in a two-replicate Keratinosens test was 31.5 µg/mL (Imax 2.15) and 21.9 µg/mL (Imax 5.10). Since the Imax was above 1.5, the test is concluded positive. Therefore, zinc naphthenate (neutral) should be considered a sensitiser for classification under CLP. REACH and CLP require an assessment of potency for sensitisers, as either Category 1A or 1B (strong/extreme or moderate, respectively). At the current time, the in vitro assays alone are not capable of this discrimination. A weight of evidence assessment has been undertaken to distinguish between a category 1A or 1B skin sensitisation classification for the substance.
Simple metal salts of organic acids (e.g. Zn, Na, K, Ca, etc.) are considered to be in the dissociated form when they become bioavailable. Therefore, the overall hazard of the salt will be determined by the hazards of both the acid and the metal cation. This principle justifies the consideration of data from naphthenic acid and other metal naphthenate salts in the weight of evidence review for zinc naphthenate (neutral).
Information from a range of sources provides data on the sensitisation potency of naphthenic acids and its salts. A publication by Yamano et al (2006, Klimisch 2) examines the allergenicity and cross-reactivity of naphthenic acids and its metal salts in animals. Further, naphthenic acids, zinc naphthenate (basic) and potassium naphthenate have all been registered under REACH and data for sensitisation is available for these substances on the ECHA dissemination portal. A summary of the data for the relevant structural analogues is as follows:
Naphthenic acids
Current classification in the ECHA dissemination portal: Skin sensitisation category 1, H317
· Publication (Yamano 2006): GPMT (guinea pig maximisation test); naphthenic acid and Cu, Zn, Co salts; positive (4/5 response in challenged animals for naphthenic acids)
· Publication (Yamano 2006): LLNA (local lymph node assay); naphthenic acid and Cu, Zn, Co salts; equivocal
· QSAR: positive
Zinc naphthenate (basic)
Current classification in dissemination portal: Non-classified
· Read across: GPMT; ZnO; negative
· Read across: LLNA; ZnO; equivocal
· Publication (Yamano 2006): GPMT; naphthenic acid and Cu, Zn, Co salts; positive (3/5 response in challenged animals for zinc naphthenate (basic))
· Publication (Yamano 2006): LLNA; naphthenic acid and Cu, Zn, Co salts; equivocal
· QSAR: positive
Potassium naphthenate
Current classification in dissemination portal: Non-classified
· Test: Buehler; K naphthenate; negative (0/20 responses in the test group)
Yamano (2006)
The Yamano paper provides a summary of skin sensitisation results for naphthenic acids and its copper, zinc and cobalt salts using in vivo GPMT and LLNA studies. On the basis that the cobalt cation has well-known sensitisation properties, the results from this salt have been excluded in this weight of evidence review. In the various dossiers on the ECHA portal, this paper (and hence the results contained therein) has been given Klimisch 2 scoring. There are limited details on experimental methodology, although the basic details reported indicate the studies were likely to have been conducted to the relevant OECD guidelines, with the exception of the GPMT where there were only 5 animals in each of the test groups. The LLNA studies were conducted according to a non-radiolabelled protocol.
The paper reports that there was an indication of an increase in ear thickness in the LLNA studies, which is a marker of skin irritation. However, significant increases in the Stimulation Index (SI) (>1.6 for this method) preceding ear thickness were observed with the zinc naphthenate salt. The result for naphthenic acid was considered equivocal, where excessive skin thickness (an indicator of irritation) was seen at or just above the Stimulation Index (SI) threshold for sensitisation. For this reason, these LLNA studies where irritation coincided with the SI threshold were considered to give equivocal results, i.e. not conclusive.
It was suggested by the authors of the paper that the main antigenic determinant of the various salts of naphthenic acid is the structure of the acid, and that the metal moieties modulate their allergenicity, with cobalt naphthenate being identified as the most potent (as a result of the known sensitisation of this cation), followed by zinc and the acid itself. However, it was also reported that copper naphthenate failed to induce sensitisation in guinea pigs. Additional published information also indicates that copper naphthenate is not a sensitiser (US EPA Reregistration eligibility decision for copper and zinc naphthenate salts, 2007), while the EU harmonised classification (Annex VI of CLP) does not classify this salt for skin sensitisation.
Beuhler test on potassium naphthenate
The registration dossier for potassium naphthenate indicates that it was subjected to a Buehler test in guinea pigs as part of its REACH registration was also considered to be negative and is not part of the Yamano series of investigations. The Buehler test on potassium naphthenate would be expected to be less sensitive than the GPMT and mirrors the LLNA in that the test substance administration is dermal, albeit in a different species (guinea pig versus mouse) and different application and measurement regimens.
Conclusion
Presently, no simple metal salts of naphthenic acid, or the acid itself, have been subject to in vitro sensitisation testing. Therefore, it is not possible to determine whether the results from in vitro studies would mirror the results reported with the GPMT and LLNA. Naphthenic acid is currently classified skin sensitisation category 1, H317. The similar classification for the cobalt salt is not so relevant since the cobalt ion is a known allergen. The potassium salt is not classified based on the results from a Buehler assay. Nevertheless, it is apparent that there is some allergenic potential associated with these substances, and this is reflected in the positive response seen in the Keratinosens assay with the registered substance.
References
United States Environmental Protection Agency. 2007. Reregistration eligibility decision for copper and zinc naphthenate salts (Case 3099). Prevention, Pesticides and Toxic Substances (7510P). EPS 739-R-07-003.
Yamano T, Shimizu M, Noda T (2006) Allergenicity and cross-reactivity of naphthenic acid and its metallic salts in experimental animals. Contact Dermatitis. 54, 25-28.
Justification for classification or non-classification
The major difference between sensitisation Category 1A and 1B is the general concentration limit (GCL) for mixtures – 0.1% (or 0.001% for strong sensitisers), and 1% respectively. The generic Category 1 (which is currently applied to naphthenic acids) is 1%, equivalent to Category 1B. Overall, it is proposed that zinc naphthenate (neutral) is classified as Category 1B on the following basis:
· GCL for Category 1B is the same as the classification of Category 1 for naphthenic acids
· Potassium naphthenate is not classified based on the results from a Buehler study
· The published data does not show consistency in quantitative (LLNA) and qualitative (GPMT) published results
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.