Naphthalene sulfonic acid, reaction products with isobutanol,sodium salts

Endpoint summary

Description of key information

No data is available on the product Sodium diisobutylnaphthalenesulphonate (ANS DIB; C8-alkyl naphthalene sulfonate) itself. Evaluation is based on read-across to the comparable C7-alkyl naphthalene sulfonate ANS IP and other substances in the Alkyl Naphthalene Sulfonates (ANS) category.

Bis(1-methylethyl)-, methyl naphthalenesulfonate, sodium salt (Sodium C₇-alkyl naphthalene sulfonate; ANS IP)was found to be corrosive in BCOP test, and was irritating to rabbit skin following 4 hours exposure.

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Endpoint:

skin irritation: in vivo

Type of information:

read-across based on grouping of substances (category approach)

Adequacy of study:

key study

Study period:

2017-08-10 to 2017-11-03

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

See chapter 13 for support for read-across within the category of Alkyl Naphthalene Sulfonates (ANS).

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Version / remarks:

version 2015

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

GLP compliance:

yes (incl. QA statement)

Remarks:

Bayerisches Landesamt für Gesundheit und Lebensmittelsicherheit, München, Germany

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

Housing and Feeding Conditions:
- Semi barrier in an air-conditioned room
- Temperature: 18 +/- 3 °C (recommendations of TVT, GV-SOLAS)
- Relative humidity: 55 +/- 10%
- Artificial light, sequence being 12 hours light, 12 hours dark
- Air change: at least 10 x / hour
- Free access to autoclaved hay and to Altromin 2123 maintenance diet for rabbits, rich in crude fibre
- Free access to tap water (drinking water, municipal residue control, microbiological controls at regular intervals)
- Certificates of food, water and bedding are filed for two years at BSL Munich and afterwards archived at Eurofins Munich
- Housed in ABS-plastic or Noryl rabbit cages, floor 4200 cm2
- Adequate acclimatisation period (at least 5 days) under laboratory conditions

Type of coverage:

semiocclusive

Preparation of test site:

clipped

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

Dose Level
A dose of 0.5 g of the test item was applied to each test site.

Duration of treatment / exposure:

Exposure Period
The test item was held in contact with the skin throughout a 4-hour period.
At the end of the exposure period, the residual test item was removed with sterile water.

Observation period:

Observation Period
Due to the persistent lesions 72 hours after the patch removal, the observation period was extended in order to evaluate the reversibility or irreversibility of the lesions. Therefore, animal no. 1 was observed for 8 days, animal no. 2 and 3 were observed for 14 days.

Number of animals:

3

Details on study design:

Clinical Observation
The animals were examined for signs of erythema and oedema 1 hour after the patch removal. For the determination of classification-relevant values, the animals were examined for signs of erythema and oedema 24, 48 and 72 hours after the patch removal. Dermal irritation was scored and recorded according to the grades in the table below. Any other signs such as hyperplasia, scaling, discolouration, fissures and scabs or any systemic effects were also recorded.
For the initial test in one animal, the test site was also examined immediately after the patch had been removed.

Evaluation of Results
Individual reactions for each animal were recorded according to the scoring system described in the table below at each time of observation.
Nature, severity and duration of clinical observations were described.
The body weight changes were summarised in a tabular form.

Irritation parameter:

erythema score

Basis:

mean

Time point:

24/48/72 h

Score:

1.9

Max. score:

4

Reversibility:

not fully reversible within: 14 days. fully reversible within up to 8 days in animal no. 1 but not reversible in animal no. 2 and 3 both showing a persistent grade 1 erythema.

Irritant / corrosive response data:

Initial test in animal no. 1: The examination of the test site immediately after the patch removal revealed erythema grade 1.
The subsequent clinical observations causes skin irritation (erythema grade 1 and 2, oedema grade 1) but no corrosive effects in animal no. 1, 2 and 3. These signs of irritation were not reversible within the observation period of 14 days in animal no. 2 and 3.

Other effects:

No mortalities were observed. No adverse changes apart from the reactions described above were observed at the skin sites.
There were no significant body weight changes during the observation period.

Interpretation of results:

Category 2 (irritant) based on GHS criteria

Remarks:

Migrated information Criteria used for interpretation of results: OECD GHS

Conclusions:

Under the conditions of the present study, the single dermal application of the test item Naphthalenesulfonic acid, bis(1-methylethyl)-, methyl derivs., sodium salt to three rabbits at a dose of 0.5 g causes skin irritation but no corrosive effects which were fully reversible within up to 8 days in animal no. 1 but not reversible in animal no. 2 and 3.
Neither mortalities nor significant clinical signs of toxicity were observed.

Executive summary:

Summary Results

Species/strain:                                       New Zealand White Rabbits Crl: KBL (NZW)

Number of animals:                              3

Duration of exposure:                           4 hours

Amount of substance:                          0.5 g per test site

Vehicle (moistening):                           aqua ad injectionem

First time of effects:                              animal no. 1: immediately after patch removal erythema grade 1

animal no. 2 and no. 3: 1 hour after patch removal erythema grade 1

Last time of effects:                              animal no. 1: 7 days after patch removal erythema grade 1

animal no. 2 and no. 3: 14 days after patch removal erythema grade 1

Reversibility of the observed effects:  animal no. 1: the changes were fully reversible within 8 days after patch removal.

animal no. 2 and 3: the changes were not reversible within the observation period.

Method: OECD 404, EC 440/2008, Method B.4, OPPTS 870.2500

Average Irritation Scores – (24, 48, 72-hour reading) – and Total Mean Value

Mean Value Irritation Scores
Animal No.	Mean 24 – 72 hours
	Erythema	Oedema
1	2	0.33
2	2	1
3	1.67	0
Total Mean Value	1.9	0.44

Conclusion

Under the conditions of the present study, the single dermal application of the test itemNaphthalenesulfonic acid, bis(1-methylethyl)-, methyl derivs., sodium saltto three rabbits at a dose of 0.5 g causes skin irritation but no corrosive effects which were fully reversible within up to 8 days in animal no. 1 but not reversible in animal no. 2 and 3.

Neither mortalities nor significant clinical signs of toxicity were observed.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irritating)

Eye irritation

Link to relevant study records

Reference

Endpoint:

eye irritation: in vitro / ex vivo

Type of information:

read-across based on grouping of substances (category approach)

Adequacy of study:

key study

Study period:

2016-10-17 to 2017-01-05

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

See chapter 13 for support for read-across within the category of Alkyl Naphthalene Sulfonates (ANS).

Qualifier:

according to guideline

Guideline:

OECD Guideline 437 (Bovine Corneal Opacity and Permeability Test Method for Identifying i) Chemicals Inducing Serious Eye Damage and ii) Chemicals Not Requiring Classification for Eye Irritation or Serious Eye Damage)

Version / remarks:

adopted: 26 July 2013

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Bayerisches Landesamt für Gesundheit und dLebensmittelsicherheit, München, Germany)

Species:

cattle

Strain:

not specified

Details on test animals or tissues and environmental conditions:

SOURCE OF COLLECTED EYES
- Source: 1452486
- Number of eyes used in test: 9
- Characteristics of donor animals (e.g. age, sex, weight): no data
- Storage, temperature and transport conditions of ocular tissue (e.g. transport time, transport media and temperature, and other conditions): transported in HBSS containing Pen/Strep on ice to the laboratories. Immediately after
arrival of the eyes, cornea preparation was initiated.
- Time interval prior to initiating testing: Tested same day of slaughter of animals
- indication of any existing defects or lesions in ocular tissue samples: Before the corneas were mounted in corneal holders they had been visually examined for defects and any defective cornea had been
discarded.
- Indication of any antibiotics used: penicillin/streptomycin was used in HBSS used for transport between slaugther house and test facility

Vehicle:

physiological saline

Amount / concentration applied:

The test item was suspended with physiological saline 0.9% NaCl (B. Braun Melsungen, lot no. 1406805, expiry date: 05/2017) to give a 10% concentration. 750 µL of the test substance or the control substance was introduced into the anterior chamber.

Duration of treatment / exposure:

After 10 minutes incubation at 32 +/- 1 °C either the test substance or the control substance was removed and the epithelium washed at least three times with MEM (containing phenol red).

Observation period (in vivo):

1 mL of a 4 mg/mL sodium fluorescein solution was added to the anterior chamber and the corneas were incubated for 90 minutes at 32 +/- 1 °C.

Duration of post- treatment incubation (in vitro):

incubated for 90 minutes at 32 +/- 1 °C

Number of animals or in vitro replicates:

3 corneas for the test item
3 corneas as negative controls treated with physiological saline 0.9% NaCl
3 corneas as positive controls treated with ethanol 100%

Details on study design:

Test System

Preparation of the Corneas:
The assay uses isolated corneas obtained as a by-product from animals freshly slaughtered at the abattoir A. Moksel AG, Buchloe, Germany.
On the test day, fresh eyes were collected from the slaughterhouse and were transported in HBSS containing Pen/Strep on ice to the laboratories. Immediately after arrival of the eyes, cornea preparation was initiated.
The eyes were carefully examined for defects and any defective eyes were discarded.
The tissue surrounding the eyeball was carefully pulled away and the cornea was excised leaving a 2 to 3 mm rim of sclera. The isolated corneas were stored in a petri dish containing HBSS. Before the corneas were mounted in corneal holders (Duratec GmbH) with the endothelial side against the O-ring of the posterior chamber, they had been visually examined for defects and any defective cornea had been discarded. The anterior chamber was then positioned on top of the cornea and tightened with screws. The chambers of the corneal holder were then filled with RPMI (without phenol red) containing 1% FBS and 2 mM L-glutamine (complete RPMI). The posterior chamber was always filled first. The corneas were incubated for one hour at 32 +/- 1 °C.


Calibration of the Opacitometer:
The opacitometer (BASF-OP3.0, Duratec GmbH) was switched on at least 15 min before starting the calibration procedure. The filter holder was placed into the opacitometer and the readout was adjusted to 1000 lux ± 10 lux using the “Calibrate”-turning knob. For calibration the glass filter F2 was introduced into the filter holder. The readout lied in the range between 540-560 lux. To test the linearity of the measurement, two additional calibration filters, glass filter F3 and glass filter F4, were measured. For these glass filters, the opacitometer displayed values between 300-310 lux and between 95-105 lux. The calibration procedure was performed before the test and is documented in the raw data.

Treatment of the Corneas:
After the equilibration period, the medium was removed from both chambers and replaced with fresh complete RPMI. An initial measurement was performed on each of the corneas using the opacitometer. Three corneas with illuminance readings approximately equivalent to the median illuminance of all corneas were selected as negative-control corneas. The illuminance of each cornea was read and recorded. Only corneas that had an initial illuminance reading I > I0/1.1651 lux were used for the assay. The medium was removed from the anterior chamber and replaced with the test item or control.
750 µL of the test substance or the control substance was introduced into the anterior chamber. After 10 minutes incubation at 32 +/- 1 °C either the test substance or the control substance was removed and the epithelium washed at least three times with MEM (containing phenol red). Once the medium was free of test substance, the cornea was finally rinsed with complete RPMI (without phenol red). The anterior chamber was refilled with complete RPMI and an illuminance measurement was performed after 2 hours incubation at 32 +/- 1 °C. Also, each cornea was observed visually and pertinent observations were recorded.
After the illuminance measurement was performed, the medium was removed from both chambers of the holder. The posterior chamber was refilled with fresh complete RPMI. 1 mL of a 4 mg/mL sodium fluorescein solution was added to the anterior chamber and the corneas were incubated for 90 minutes at 32 +/- 1 °C. Then the medium from the posterior chamber was removed and its optical density at 490 nm (OD490) was determined, using a spectrophotometer (Jenway 6405 UV/VIS).


Test Groups:
3 corneas for the test item
3 corneas as negative controls treated with physiological saline 0.9% NaCl
3 corneas as positive controls treated with ethanol 100%
The BCOP assay is considered to be valid if the in vitro irritation score obtained with the positive control falls within the two standard deviations of the current historical mean.
The negative control responses should result in opacity and permeability values that are less than the established upper limits for background bovine corneas treated with the respective negative control.


Evaluation of Results:
The following formula was used to calculate the opacity, whereas the values a and b are equipment-specific variables empirically determined by the manufacturer:

Opacity = (I0/I - b)/a

with a = 0.025 and b = 0.9894

The value I0 = I(zero) is the illuminance through a holder without cornea, but with windows and liquid. This value is determined by taking the mean for a set of cornea holders and is reevaluated periodically.
The change in opacity for each cornea was calculated by subtracting the initial opacity reading from the final opacity reading. These values were corrected by subtracting from each the average change in opacity observed for the negative-control corneas. The mean opacity value for each treatment was calculated by averaging the corrected opacity values of each cornea for a given treatment.
The mean OD490 for the blank cuvettes was calculated. The mean blank OD490 was subtracted from the OD490 of each cuvette (corrected OD490). Any dilutions that were made to bring the OD490 values into the linear range of the spectrophotometer (OD490 should be less than 1.500), were taken into account by multiplying the OD490 value of the dilution by the dilution factor. The final-corrected OD490 of the test article and the positive control were calculated by subtracting the average-corrected OD490 of the negative-control corneas from the corrected OD490 value of each treated cornea:
Final-corrected OD490 = (OD490 – mean blank OD490) – average-corrected negative control OD490
The mean OD490 value of each treatment group was calculated by averaging the final corrected OD490 values of the treated corneas for that treatment condition.
The following formula was used to determine the in vitro irritation score (IVIS):
IVIS = mean opacity value + (15 x mean permeability OD490 value)
The IVIS cut-off values for identifying test substances as inducing serious eye damage (UN GHS Category 1) and test substances not requiring classification for eye irritation or serious eye damage (UN GHS No Category) are given in the table below.

An identification of test substances that should be classified as irritating to eyes (UN GHS Category 2 or Category 2A) or test substances that should be classified as mildly irritating to eyes (UN GHS Category 2B) cannot be made.
For this purpose further testing with another suitable method is required

Irritation parameter:

in vitro irritation score

Value:

73.62

Vehicle controls validity:

valid

Remarks:

physiological saline 0.9% NaCl

Negative controls validity:

valid

Remarks:

physiological saline 0.9% NaCl

Positive controls validity:

valid

Remarks on result:

positive indication of irritation

Remarks:

IVIS above > 55 is interpreted as Category 1

Irritant / corrosive response data:

The eye irritancy potential of Glucamide CC was investigated in the bovine corneal opacity and permeability assay.
The test item was suspended with physiological saline 0.9% NaCl to gain a 10% concentration.
The following mean in vitro irritation score was calculated:
73.62

Interpretation of results:

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

Conclusions:

According to the evaluation criteria the test item Naphthalenesulfonic acid, bis(1-methylethyl)-, methyl derivs., sodium salt is classified into UN GHS Category 1.

Executive summary:

 

Summary Results

The eye irritancy potential of Naphthalenesulfonic acid, bis(1-methylethyl)-, methyl derivs., sodium salt was investigated in the bovine corneal opacity and permeability assay.

Preparation of the test item:                     

The test item is a neat surfactant and will be tested at a concentration of 10% w/v in a 0.9% sodium chloride solution, if technically possible, according to OECD Guideline.

Visual Observation after treatement:        

All 3 corneas treated with Naphthalenesulfonic acid, bis(1-methylethyl)-, methyl derivs., sodium salt showed a complete opacity of the tissue.

Mean in vitro irritation score:                    73.62

 

	UN GHS No Category
	No prediction can be made
X	UN GHS Category 1

Classification:                                       

The in vitro irritation score obtained with the positive control fell within the two standard deviations of the current historical mean and therefore this assay is considered to be valid.

The negative control responses should result in opacity and permeability values that are less than the established upper limits for background bovine corneas treated with the respective negative control.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irreversible damage)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

No data is available on the product Sodium diisobutylnaphthalenesulphonate (ANS DIB; C8-alkyl naphthalene sulfonate) itself. Evaluation is based on read-across to the comparable C7-alkyl naphthalene sulfonate (ANS IP) and other substances in the Alkyl Naphthalene Sulfonates (ANS) category. See chapter 13 for support for read-across within the category of Alkyl Naphthalene Sulfonates (ANS).

 

Skin irritation/corrosion:

Bis(1-methylethyl)-, methyl naphthalene sulfonate, sodium salt (Sodium C7-alkyl naphthalene sulfonate; ANS IP) was tested for skin irritation in the in vitro skin irritation test using the EpiSkin human epidermis model (OECD 439). 10 ± 2 mg + 5 µL aqua dest. were applied topically for 15 minutes. After 42 h post-incubation cytotoxic effects were determined via MTT reduction assay. As tissue viability was not reduced compared to control, and it was concluded that the substance was not irritant under the conditions of this study.

However, the very similar C10-13-alkylnaphthalene sulfonate (ANS N) also pointed to a complete lack of irritation potential in testing in an EPISKIN in vitro skin irritation test, showing a viability score of 105%. But upon subsequent in vivo testing, the 4 hr exposures to the rabbit skin led to a maximal irritation score, even with superficial necrosis.

 

In order to confirm the suggested non-irritating properties of Sodium C7-alkyl naphthalene sulfonate in vivo, a primary skin irritation/corrosion study was conducted in the rabbit (semi-occlusive application) according to OECD 404. 0.5 g of test substance was moistened with water and applied on the skin of 3New Zealand White Rabbits and fixed with a semi-occlusive dressing for 4 hours. At the end of the exposure period, the residual test item was removed with sterile water. Upon clinical observations, the substance was shown to cause erythema grade 1 and 2, oedema grade 1, but no corrosion. In one animal signs of irritation were reversible in 8 days. The other two animals still showed a grade 1 erythema on day 14, the end of the observation period.

 

Eye irritation:

Sodium C7-alkyl naphthalene sulfonate (ANS IP) was also tested the in vitro Bovine Corneal Opacity and Permeability Assay (BCOP, OECD 437). The test item was considered to be a neat surfactant and was tested at a concentration of 10% w/v in a 0.9% sodium chloride solution for the standard exposure duration of 10 minutes. All three corneas exposed to the test substance showed a complete opacity of the tissue, and the mean in vitro irritation score was 73.62.

Justification for classification or non-classification

Based on persisting erythema in two of the three animals at the end of the observation period in thein vivoskin irritation study in rabbits, the product need to be classified for CLP as: skin irritant (Category 2) with H315: Causes skin irritation.

The results from the in vitro eye irritation study (BCOP) showed an IVIS score of 73.62. IVIS above > 55 result to classification for CLP with Category 1, H318: Causes serious eye damage.

 

There is no information on possible respiratory irritation, so no conclusion can be made regarding STOT SE cat.3 classification for Respiratory tract irritation.