Ethyl palmitate

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

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

Adequacy of study:

key study

Justification for type of information:

See "Assessment reports" section 13 or "Categories" section for the justification and rationale document for category approach.

Materials and methods

Test material

Test material information

Constituent 1

Reference substance name:

Ethyl palmitate

EC Number:

211-064-6

EC Name:

Ethyl palmitate

Cas Number:

628-97-7

Molecular formula:

C18H36O2

IUPAC Name:

ethyl hexadecanoate

Results and discussion

Effect levels

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Any other information on results incl. tables

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	Acute dermal Toxicity
Isopropyl myristate	110-27-0	C14	Isopropanol	270,46	Liquid	no data
Isopropyl palmitate	142-91-6	C16	Isopropanol	298.51	Liquid	no data
Ethyl linoleate	544-53-4	C18:2	ethanol	308,5	Liquid	Experimental result: LD50 > 2000 mg/kgbw
Ethyl oleate	111-62-6	C18:1	ethanol	310.52	Liquid	no data
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	no data

 

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.

One dermal acute study was performed for the ethyl linoleate, according to OECD 402 method. Rats were exposed and the LD50 was defined to be higher than 2000 mg/kgbw.

 The experimental study is consistent with the experimental studies performed for skin irritation. No toxicity was observed when the substances were applied dermally. Hence, no acute dermal toxicity is expected. 

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Based on the available experimental study performed on one source substance of the category, none of these showed adverse effect for acute dermal toxicity on rodents. Hence, no classification is required for category substances according to REACh regulation and the category approach.

Executive summary:

According to the Regulation (EC) NO. 1907/2006, Annex XI, 1.5, A read-across category for short chain fatty acid was performed in order to provide informations on 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.

The category substances are fatty acid esters covering chain length C8 to C18 satured or unsatured linked to alcohol including ethanol, isopropanol, octanol, hexanol and 2-ethylhexanol. These substances showed similar physico-chemical properties as very low solubility in water, not volatile, ready biodegradable and high log Kow. The substances are expected to have same toxicity behavior according to the common structural and physico-chemical similarities. Indeed, they are expected to be hydrolyzed in same way when applied dermally.

As expected, none of the acute dermal toxicity tests performed showed adverse effect. Hence, the category substances are not classified for acute dermal hazard according to CLP criteria.