Alkylated Naphthalene

Endpoint summary

Description of key information

3 studies were performed:
- an in vitro skin irritation test showed no irritation 
- an in vitro eye irritation test showed no irritation or corrosion
- an in vivo rabbit eye irritation test showed no irritation or corrosion

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Endpoint:

skin irritation / corrosion

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Eye irritation

Link to relevant study records

Reference

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Study in-life phase Start : 15 April 2013 Completion : 25 April 2013

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP Guideline study without deficiencies

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

Species: Albino rabbit, New Zealand White, (SPF-Quality).

Source: Charles River France, L’Arbresle Cedex, France
Number of animals 3 Males.
Age and body weight Animals used within the study were between 12 and 24 weeks old and
body weights were at least 1.5 kg.
Identification Earmark.
Health inspection At least prior to dosing. It was ensured that the animals were healthy and
that the eyes were free from any abnormality.

Animal husbandry
Conditions:
Environmental controls for the animal room were set to maintain 18 to 24°C, a relative humidity of 40
to 70%, approximately 15 room air changes/hour, and a 12-hour light/12-hour dark cycle. Any
variations to these conditions were maintained in the raw data and had no effect on the outcome of the
study.
Accommodation
Animals were individually housed in labeled cages with perforated floors (Ebeco, Germany,
dimensions 67 x 62 x 55 cm) and shelters (Ebeco, Germany, dimensions 40 x 32 x 23 cm).
Acclimatization period was at least 5 days before start of treatment under laboratory conditions.
Diet
Pelleted diet for rabbits (Global Diet 2030 from Harlan Teklad®, Mucedola, Milanese, Italy)
approximately 100 grams per day. Hay (TecniLab-BMI BV, Someren, The Netherlands) and wooden
sticks (Swedish aspen wood, Bioservices, Uden, The Netherlands) were available during the study
period
Water
Free access to tap water.
Diet, water, bedding and cage enrichment evaluation for contaminants and/or nutrients was performed
according to facility standard procedures. There were no findings that could interfere with the study.

Vehicle:

unchanged (no vehicle)

Controls:

not required

Amount / concentration applied:

0.1 mL

Duration of treatment / exposure:

24 hours

Observation period (in vivo):

72 hours

Number of animals or in vitro replicates:

3

Details on study design:

Each animal was treated by instillation of 0.1 mL of the test substance, in the conjunctival sac of one
of the eyes after gently pulling the lower lid away from the eyeball. The lids were then gently held
together for about one second to prevent loss of the test substance. The other eye remained untreated
and served as the reference control.
Immediately after the 24-hour observation, a solution of 2% fluorescein (Merck, Darmstadt, Germany)
in water (adjusted to pH 7.0) was instilled into both eyes of each animal to quantitatively determine
corneal epithelial damage. Any bright green stained area, indicating epithelial damage, was estimated
as a percentage of the total corneal area.
In order to provide a continued level of systemic analgesia, buprenorphine 0.01 mg/kg and meloxicam
0.5 mg/kg were administered by subcutaneous injection following the 24 hours observation.
After the final observation, the animals were sacrificed by intra-venous injection of Euthasol® 20%
(AST Farma BV, Oudewater, The Netherlands).

Observations:
Mortality/Viability Twice daily.
Toxicity At least once daily.
Body Weight Day of treatment (prior to instillation) and after the final observation.
Necropsy No necropsy was performed according to protocol.
Irritation The eyes of each animal were examined approximately 1, 24, 48 and 72
hours after instillation of the test substance. The irritation scores and a
description of all other (local) effects were recorded.

Irritation parameter:

overall irritation score

Basis:

mean

Time point:

other: 24

Score:

ca. 0

Max. score:

0

Irritation parameter:

overall irritation score

Basis:

mean

Time point:

other: 48

Score:

ca. 0

Max. score:

0

Irritation parameter:

overall irritation score

Basis:

mean

Time point:

other: 72

Score:

ca. 0

Max. score:

0

Irritant / corrosive response data:

Instillation of 0.1 mL of Alkylated Naphthalene into one eye of each of three rabbits resulted in irritation of the conjunctivae,
which consisted of redness, chemosis and discharge. The irritation had completely resolved within 24
hours.
No iridial irritation or corneal opacity were observed, and treatment of the eyes with 2% fluorescein 24
hours after test substance instillation revealed no corneal epithelial damage.

There was no evidence of ocular corrosion.

Other effects:

No mortality or clincal symptoms

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Alkylated Naphthalene is not irritating or corrosive to the eye.

Executive summary:

An acute eye irritation/corrosion study was conducted with Alkylated Naphthalene in the rabbit. The study was carried out based on the guidelines described in: OECD No.405 (2012) "Acute Eye Irritation / Corrosion". Single samples of 0.1 mL of Alkylated Naphthalene were instilled into one eye of each of three rabbits. Observations were made 1, 24, 48 and 72 hours after instillation. Instillation of the test substance resulted in irritation of the conjunctivae, which consisted of redness, chemosis and discharge. The irritation had completely resolved within 24 hours. No iridial irritation or corneal opacity were observed, and treatment of the eyes with 2% fluorescein 24 hours after test substance instillation revealed no corneal epithelial damage. There was no evidence of ocular corrosion. Based on these results, Alkylated Naphthalene does not have to be classified and has no obligatory labeling requirement for eye irritation according to the Globally Harmonized System of Classification and Labelling of Chemicals (GHS) of the United Nations (2011) and Regulation (EC) No 1272/2008 of the European Parliament and of the Council of 16 December 2008 on classification, labelling and packaging of substances and mixtures including all amendments.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Additional information

Alkylated Naphthalene was shown in all tests to lack irritation or corrosion properties for eye and skin.

An in vivo skin irritation test is not required for Alkylated Naphthalene. The substance has been investigated in an EPISKIN OECD 439 respectively Method B.46 of Commission Regulation (EC) No. 440/2008/EC and was proven to be non-irritant in this test. The EU Commission has acknowledged in its Statement on the validity of in-vitro tests for skin irritation at its 26th meeting, held on 26-27th of April 2007 for the Validation of Alternative Methods (ECVAM) unanimously that the EPISKIN method showed evidence of being a reliable and relevant stand-alone test for predicting rabbit skin irritation, when the endpoint is evaluated by MTT reduction, and for being used as a replacement for the in-vivo Draize Skin Irritation Test . Consequently, for animal welfare an in-vivo test is not scientifically justifiable.

Justification for selection of skin irritation / corrosion endpoint:
Alkylated Naphthalene has been investigated in an EPISKIN OECD 439 respectively Method B.46 of Commission Regulation (EC) No. 440/2008/EC and was proven to be non-irritant in this test. The EU Commission has acknowledged in its Statement on the validity of in-vitro tests for skin irritation at its 26th meeting, held on 26-27th of April 2007 for the Validation of Alternative Methods (ECVAM) unanimously that the EPISKIN method showed evidence of being a reliable and relevant stand-alone test for predicting rabbit skin irritation, when the endpoint is evaluated by MTT reduction, and for being used as a replacement for the in-vivo Draize Skin Irritation Test . Consequently, for animal welfare an in-vivo test is not scientifically justifiable. It is also relevant that the in vivo eye test showed that the substance did not require classification for irritation effects.

Justification for selection of eye irritation endpoint:
GLP in vivo eye irritation test showed that Alkylated Naphthalene is not irritating and does not need to be classified.

Justification for classification or non-classification

Based on lack of irritation in in vitro and in vivo testing, Alkylated Naphthalene does not have to be classified and has no obligatory labeling requirement for skin or eye irritation according to the Globally Harmonized System of Classification and Labelling of Chemicals (GHS) of the United Nations (2011) and Regulation (EC) No 1272/2008 of the European Parliament and of the Council of 16 December 2008 on classification, labelling and packaging of substances and mixtures including all amendments.