Ethyl palmitate

Endpoint summary

Description of key information

According to the category approach and based on the available key studies on the source substances, the target substance Ethyl Palmitate was considered to be not irritant to skin and eye. Hence, the target substance was not classified for skin and eye irritation/corrosion.

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

Justification for type of information:

See attached report for justification and rationale of the category approach

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Remarks on result:

no indication of irritation

Table 1: Results from key studies performed on the source substances of the category

Common name	CAS	Fatty acid chain length	Type of alcohol	MW	Appareance	Skin irritation or skin corrosion
Isopropyl myristate	110-27-0	C14	Isopropanol	270,46	Liquid	Experimental result: Not  irritating
Isopropyl palmitate	142-91-6	C16	Isopropanol	298.51	Liquid	Experimental result: Not  irritating
Ethyl linoleate	544-53-4	C18:2	ethanol	308,5	Liquid	Experimental result: Not  irritating
Ethyl oleate	111-62-6	C18:1	ethanol	310.52	Liquid	Experimental result: Not  irritating
Fatty acids, C16-18, butyl esters	85408-76-0	C16-18	Butanol	312.53 – 340.58	Paste	no data
Fatty acids, C16-18 and C18-unsatured, isobutyl esters	84988-79-4	C16-18, C18:1	Isobutanol	312.53 – 340.58	Liquid	no data
Isopropyl isostearate	68171-33-5	C18iso	Isopropanol	326.56	Liquid	Experimental result: Not  irritating

 

According to the current literature, esterase enzymes were present into the skin of different mammalian species (as human, rodents orminpigs). These enzymes, as carboxylesterase, hydrolyzed different substrates as xenobiotic or different ester as fatty acids esters (C. Jewell, 2007; J.J.Prusakiewicz, 2006). Based on this principle, when applied on skin, the source and the target substances are expected to be substrates of these carboxylesterase. They are hydrolyzed into fatty acids and alcohols. In the case that the products of hydrolysis could across the dermal barrier to reach systemic system, they have the same behavior as oral ingestion. The potential toxicity should bebringby these hydrolyzed products.

They are expected to be metabolized in common energetic pathways or excreted.

No experimental study was available for the target substance the Ethyl palmitate. However, several experimental in vivo studies were performed for skin irritation assessment. None of these studies showed irritation properties. The source substances and the target substance are structurally similar and showed common physic-chemical properties. Based on these properties, it can be stated that the target substance followed the same health effect for skin irritation. Hence, the ethyl palmitate was considered as not irritant to skin.

Interpretation of results:

GHS criteria not met

Conclusions:

Based on the category approach and according to the results of the available studies of the source substances, the target substance was considered to be not irritant. Hence, the ethyl palmitate was not classified for skin irritation.

Executive summary:

According to the Regulation (EC) NO. 1907/2006, Annex XI, 1.5, A Read-Across Category was performed in order to provide informations on the Ethyl Palmitate.

This category was based on common and shared physico-chemical and structural properties as:

- common functional group,

- common precursors and the likehood of common impurities as well as common breakdown products via biological processes, which are chemically structurally similar, and

- constant pattern in the changing of the potency of the properties across the category.

Based on the available studies on the source substances for skin irritation assessment, none of these susbtances showed adverse effect when applied dermally on rabbit and guinea pigs skin. According to physic-chemical similarities betsween source substances and target substance, it can be stated that the ethyl palmitate showed same toxicological profile. Hence, no classification was made for the ethyl palmitate for skin irritation.

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:

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

Adequacy of study:

key study

Justification for type of information:

See attached report for justification and rationale of the category approach (Section 0 and section 13)

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Remarks on result:

no indication of irritation

Table 1: Results from key studies performed on the source substances of the category

Common  name	CAS	Fatty  acid  chain  length	Type of  alcohol	MW	Appareance	Eye irritation
Isopropyl  myristate	110-27-0	C14	Isopropanol	270,46	Liquid	Experimental result: Not  irritating
Isopropyl palmitate	142-91-6	C16	Isopropanol	298.51	Liquid	Experimental result: Not  irritating
Ethyl  linoleate	544-53-4	C18:2	ethanol	308,5	Liquid	Experimental result: Not  irritating
Ethyl  oleate	111-62-6	C18:1	ethanol	310.52	Liquid	Experimental result: Not  irritating
Fatty acids, C16-18, butyl esters	85408-76-0	C16-18	Butanol	312.53 – 340.58	Paste	no data
Fatty acids, C16-18 and C18-unsatured, isobutyl esters	84988-79-4	C16-18, C18:1	Isobutanol	312.53 – 340.58	Liquid	no data
Isopropyl  isostearate	68171-33-5	C18iso	Isopropanol	326.56	Liquid	Experimental result: Not irritating

 

 In eye, some esterase enzyme could have the same ability to hydrolyze the category substances (V.H.L. Lee, 1982) into alcohol and fatty acids. They could vehicle potential irritation or corrosion effect. 

No experimental study was available for the target substance the Ethyl palmitate. However, Five key experimental in vivo studies were performed for eye irritation assessment. These studies were performed in vivo on rabbits or guinea pigs according to OECD 405 guideline method. None of these studies showed irritation properties. The source substances and the target substance are structurally similar and showed common physic-chemical properties. Based on the properties, it can be stated that the target substance followed the same health effect for eye irritation. Hence, the ethyl palmitate was considered as not irritant to eye.

Interpretation of results:

GHS criteria not met

Conclusions:

Based on the category approach and according to the results of the available studies of the source substances, the target substance was considered to be not irritant. Hence, the ethyl palmitate was not classified for eye irritation.

Executive summary:

According to the Regulation (EC) NO. 1907/2006, Annex XI, 1.5, A Read-Across Category was performed in order to provide informations on the Ethyl Palmitate.

This category was based on common and shared physico-chemical and structural properties as:

- common functional group,

- common precursors and the likehood of common impurities as well as common breakdown products via biological processes, which are chemically structurally similar, and

- constant pattern in the changing of the potency of the properties across the category.

In eye, some esterase enzyme could have the same ability to hydrolyze the category substances (V.H.L. Lee, 1982) into alcohol and fatty acids. They could vehicle potential irritation or corrosion effect. But, none of the source substances, which were assessed for eye irritation, showed any adverse effect on rabbit eyes as expected.

Based on the available studies on the source substances and according to physico-chemical similarities betsween source substances and target substance, it can be stated that the ethyl palmitate showed same toxicological profile. Hence, no classification was made for the ethyl palmitate.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Additional information

The category group covers alcohol linked with fatty acid chains unsatured and satured. This category includes monoconstituent chemicals and UVCB substances varying acid chain length (C14 to C18) and based on alcohol function type (including ethanol, butanol and isopropanol). This approach was performed in order to provide sufficient information for physicochemical, ecotoxicological and toxicological characterizations of the ethyl palmitate. Based on structural and physic-chemicals similarities, available experimental studies from source chemicals could be used for the target substance ethyl palmitate.

This category group includes:

-       Isopropyl myristate                                                 CAS 110-27-0

-       Isopropyl palmitate                                                 CAS 142-91-6

-       Ethyl linoleate                                                         CAS 544-35-4

-       Ethyl oleate                                                            CAS 111 -62-6

-       Fatty acids, C16 -18, butyl esters                          CAS 85408-76-0

-       Fatty acids, C16 -18 and C18-unsatured isobutyl esters              CAS 84988-79-4

-       Isopropyl isostearate                                                                     CAS 68171-33-5

-       Target substance : Ethyl palmitate                                                  CAS 628-97-7

In accordance with article 13 (1) of Regulation (EC) No. 1907.2006, “information on intrinsic properties of substances may be generated by means other than tests, provided that the conditions set out in Annex XI are met. In particular for human toxicity, environmental fate and ecotoxicity, information shall be generated whenever possible by means other than vertebrate animal tests which includes the use of information from structurally related substances (grouping or read across)”. Therefore, the available experimental data were collected and evaluated according to Annex XI requirements.

Summary of the available studies for skin irration toxicity

Isopropyl myristate CAS 110 -27 -0

Several studies were performed with the isopropyl myristate in order to assess the potential skin irritation of the substance. All the studies were performed on rabbits. The two key studies were performed according to the OECD 405 guideline and GLP compliance. New Zealand rabbits were exposed on shaved skin to 0.5 mL of substance during 4 hours (under semiocclusive condition). In the two key studies, the test substance caused very slight erythema disappearing completely within 7 days. Only one animal had slight edema up to 48 h after application. The test substance did not induce skin irritation.

Five addtional supporting studies were available. One supporting study was performed on New Zealand White rabbits. They were exposed on shaved skin to 0.5 mL of substance during 4 hours (under semiocclusive condition). Fully reversible slight effect were observed. Another study was performed under occlusive condition with same protocol. Reversible mild irritation was observed after treatment.

Three other supporting studies were performed with rabbits which were treated during 24 hours with 0.5 mL of test item. Intact skin and abraded skin were assessed. The test item was considered to be not irritating in all these studies.

Isopropyl isostearate CAS 68171 -33 -5

Two studies were available for the isopropyl isostearate. The key study was performed on New Zealand White rabbits according to OECD 404 Guideline method. They were treated on clipped skin with 0.5 mL of test item over a period of 4 hours under semiocclusive condition. Until the 72 hours of observation, only reversible slight effect were observed. The substance was not considered as irritating to skin.

The supporting study was performed on Hartley Guinea Pigs. They were treated during 30 minutes to 0.02 mL/cm2 of substance. No effect was observed.

Isopropyl palmitate CAS 142 -91 -6

Three studies were performed on the Isopropyl palmitate in order to assess the potential skin irritation potential. The key study was performed according to OECD 404 Guideline on New Zealand rabbits. 0.5mL was applied on shaved skin during 4 hours under semiocclusive condition. They were observed during a period of 14 days. Only slight reversible effect were observed.

Two supporting studies were performed too. Rabbits were exposed to test item, abraded and intact skin were assessed. Based on these studies, the substance was considered as not irritant to skin.

Ethyl oleate CAS 111 -62-6

The key study was performed according to the OECD TG 404 method. New Zealand White rabbits were treated dermally (on intact and abraded skin) under occlusive condition with 0.5 mL of unchanged test substance. Scoring was performed according Draize scoring system at 24 and 72 hours. At 24 hours, all 6 animals displayed erythema graded 1 to 2 on the intact skin; on the incised skin, erythema graded 1 to 2  was reported for 5 animals whereas the remaining one showed no erythema. At 72 hours, none of all 5 surviving animals displayed erythema or edema. The ethyl oleate was not considered as skin irritant substance.

Ethyl linoleate CAS 544 -35 -4

One in vivo key study is available to assess the potential skin irritation of the ethyl linoleate. The experimental study was conducted according to OECD TG 404, using New Zealand White rabbits. Animals were exposed to the test item in solution (at 70%) during 24 hours. Observation period was performed during 7 days and Draize scoring system was used. No adverse effect was observed. The substance was not considered as irritant for skin.

Based on the avalaible studies on source chemicals of the category, it can be stated that the target substance Ethyl Palmitate did not induced skin irritation.

Summary of the available studies for eye irration toxicity

Isopropyl myristate CAS 110 -27 -0

Three studies were available to assess the potental eye irritation of the Isopropyl myristate. The key study was performed with a method similar to OECD 405 method. New Zealand White rabbits were used. 0.1 mL of test substance was instilled in eye. Animals were observed during a period of 7 days. After instillation of the test substance into rabbit eyes there was slight conjunctival irritation observed, that was reversible after 48h.

In the two additionnal supporting studies, method similar to OECD 405 was used. Rabbit eye was instilled with 0.1 mL of the test item in single administration. Animals were observed during 72 hours or 7 days. No adverse effect were obseved. Based on the results of the key and supporting studies, the isopropyl myristate was not considered as eye irritant.

Isopropyl isostearate CAS 68171 -33 -5

One key study was performed to assess eye irritation potential of the Isopropyl isostearate. The study was performed according to OECD 405 Guideline and GLP compliance. New Zealand White rabbits were used. 0.1 mL of test substance was instilled in eye. Animals were observed during a period of 72 days. After instillation of the test substance into rabbit eyes there were slight conjunctival redness observed and lacrimation, that was reversible after 48h. Hence, the test substance was not considered as eye irritant.

Isopropyl palmitate CAS 142 -91 -6

One key study was performed to assess eye irritation potential of the Isopropyl isostearate. The study was performed with a method similar to OECD 405 Guideline. Rabbits were used. 0.1 mL of test substance was instilled in eye and were exposed duriong 24 hours. Animals were observed during a period of 72 days. After a single instillation the test substance causes mild irritations to rabbit eyes that were fully reversible within 72h. Hence, the test substance was not considered as eye irritant.

Ethyl linoleate 544 -35-4

One in vivo key study is available to assess the potential eye irritation of the ethyl linoleate. The experimental study was conducted according to OECD TG 405, using New Zealand White rabbits. Animals were exposed to the test item by instillation. Observation period was performed during 7 days after the treatment and Draize scoring system was used. No adverse effect was observed. The substance was not considered as irritant for eyes.

Based on the avalaible studies on source chemicals of the category, it can be stated that the target substance Ethyl Palmitate did not induced eye irritation.

Justification for classification or non-classification

According to the category approach and based on the available key studies on the source substances, the target substance Ethyl Palmitate was considered to be not irritant to skin and eye. Hence, the target substance was not classified for skin and eye irritation/corrosion.