Registration Dossier

Administrative data

Endpoint:
basic toxicokinetics in vitro / ex vivo
Type of information:
other: Expert statement
Adequacy of study:
supporting study
Reliability:
4 (not assignable)
Rationale for reliability incl. deficiencies:
other: see 'Remark'
Remarks:
In order to fulfill the requirements for submission of a REACH dossier according to Annex IX of REACH Regulation (EC) No.1907/2006 (for substances >100 tones/year) and in absence of data on the toxicokinetics and dermal absorption, an assessment of toxicological behaviour is required. No studies are available on the toxicokinetics, metabolism and distribution of 1,1,4,4-tetramethylbutane-1,4-diyl bis(2-ethylperoxyhexanoate).The available physico-chemical and toxicological information of the substance has been evaluated and used to assess the toxicological behaviour.

Data source

Materials and methods

Test material

Reference
Name:
Unnamed
Type:
Constituent

Results and discussion

Applicant's summary and conclusion

Executive summary:

Basic Toxicokinetics for 1,1,4,4-tetramethylbutane-1,4-diyl bis(2-ethylperoxyhexanoate) (CAS# 13052-09-0)

 

In order to fulfill the requirements for submission of a REACH dossier according to Annex IX of REACH Regulation (EC) No.1907/2006 (for substances >100 tones/year) and in absence of data on the toxicokinetics and dermal absorption, an assessment of toxicological behaviour is required. No studies are available on the toxicokinetics, metabolism and distribution of 1,1,4,4-tetramethylbutane-1,4-diyl bis(2-ethylperoxyhexanoate).

 

The molecular structure of 1,1,4,4-tetramethylbutane-1,4-diyl bis(2-ethylperoxyhexanoate):

 

The substance can be considered readily biodegradable and no hydrolysis study was performed. There are also no measurements to determine breakdown products.

 

Below are some physical chemical properties of 1,1,4,4-tetramethylbutane-1,4-diyl bis(2-ethylperoxyhexanoate).

 

Endpoint

1,1,4,4-tetramethylbutane-1,4-diyl bis(2-ethylperoxyhexanoate)

MW

430.618

WS

27.9 µg/L

Log Pow

>6.5 (7.1 extrapolated)

VP

The vapor pressure of test substance at 25°C is well below 0.01 Pa or 0.1 µBar. 

(In the range of 10-6 – 10-9 Pa).

Skin irritation

Not irritating

 

NOTE:1,1,4,4-tetramethylbutane-1,4-diyl bis(2-ethylperoxyhexanoate) is classified as a peroxidetype C. Flammability is an intrinsic hazard in this class.The Self-Accelerating Decomposition Temperature (SADT) of the substances is 35°C (reference SADT: CLP regulations 2.15.2.3 and UN Recommendations on the Transport of Dangerous Goods, Manual of Tests and Criteria, 5th revised edition, sub-sections 28.1, 28.2, 28.3 and Table 28.3.)

 

The available physico-chemical and toxicological information of the substance has been evaluated and used to assess the toxicological behaviour. The results of this analysis will address the question on how the chemical will react in the body.

The ECHA “Guidance on information requirements and chemical safety assessment Chapter R.7c: Endpoint specific guidance May 2008” document provides guidance, which physico-chemical properties commonly determine oral, inhalatory and dermal absorption, distribution, metabolism and elimination of substances(Link:http://echa.europa.eu/documents/10162/13632/information_requirements_r7c_en.pdf)

 

Dermal Absorption

Based on the log Pow of >6.5, vapor pressure and water solubility, the substance is not expected to penetrate the skin to a significant degree. The substance is not irritating to skin and increased absorption due to damaged skin is therefore not likely.

 

Once absorbed however, the peroxide would undergo thermal decomposition at body temperature. There is no information on the actual breakdown products formed.

 

Inhalation Absorption

The vapor pressure is<<0.01Pa 25°. Based on the low vapor pressure and pattern of use, inhalation is not expected to be a major route of exposure. If inhalation of the peroxide does occur, as stated above it will rapidly decompose. There is no information on the actual breakdown products formed.

 

Oral Absorption

A OECD422 oral gavage study in rats, resulted in effects on the kidneys of males (alpha 2μglobulin), livers of males and females (increase liver weights, diffuse hepatocellular hypertrophy) and thyroid follicular hypertrophy and minimally-slightly increased extramedullary hemopoiesis at 30 mg/kg/day. The liver effects were considered adaptive and the alpha 2μglobulin is specific to the male rat. The effects on the thyroid are a secondary effect due to increased metabolism of T3/T4 and the observations in the spleen are caused by an increased demand.

 

While it is not possible to establish the causative agent of the effects noted in the OECD422 study with the peroxide, (i.e. peroxide or breakdown products), the peroxide is expected to quickly decompose at body temperature. There is no information on the actual breakdown products formed.

 

Conclusion

While toxicokinetic data is not available on 1,1,4,4-tetramethylbutane-1,4-diyl bis(2-ethylperoxyhexanoate), if absorbed, it is expected to breakdown rapidly. There is no information on the actual breakdown products formed. 1,1,4,4-tetramethylbutane-1,4-diyl bis(2-ethylperoxyhexanoate) is not expected to bioaccumulate.