Diethylhexyl adipate

Structural formula
Structure without stereochemistry
General
Surname	Diethylhexyl adipate
other names	Bis (2-ethylhexyl) adipate ( IUPAC ) DEHA Adipic acid bis (2-ethylhexyl ester) Di-2-ethylhexyl adipate Hexanedioic acid bis (2-ethylhexyl ester) Di (2-ethylhexyl) adipate Dioctyl adipate DIETHYLHEXYL ADIPATE ( INCI )
Molecular formula	C 22 H 42 O 4
Brief description	colorless, almost odorless liquid
External identifiers / databases
CAS number 103-23-1 EC number 203-090-1 ECHA InfoCard 100.002.810 PubChem 7641 ChemSpider 7358 Wikidata Q412835
properties
Molar mass	370.64 g mol −1
Physical state	liquid
density	0.93 g cm −3
Melting point	−68 ° C
boiling point	214 ° C (6.7 hPa)
Vapor pressure	0.1 Pa (20 ° C)
solubility	practically insoluble in water (0.8 mg l −1 at 20 ° C)
Refractive index	1.4473
safety instructions
GHS labeling of hazardous substances no GHS pictograms H and P phrases H: no H-phrases P: no P-phrases
Toxicological data	9100 mg kg −1 ( LD 50 ,  rat ,  oral ) 14800 mg kg −1 ( LD 50 ,  rabbit ,  transdermal )
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . Refractive index: Na-D line , 20 ° C

Diethylhexyl adipate (DEHA) is an organic chemical compound from the ester group , more precisely the adipic acid ester of 2-ethylhexanol . Sometimes diethylhexyl adipate is incorrectly called DOA ( dioctyl adipate ).

Extraction and presentation

Is obtained industrially DEHA by esterification of adipic acid with 2-ethylhexanol at elevated temperatures in the presence of acidic catalysts such as sulfuric acid or p-toluenesulfonic acid . The crude product is purified by separating off the catalyst, neutralizing it and evaporating further impurities.

Another possibility to produce diethylhexyl adipate is the reaction between adipic anhydride and 2-ethylhexanol or by transesterification of dimethyl adipate with 2-ethylhexanol in the presence of titanium n-butoxide.

properties

Diethylhexyl adipate is a clear, colorless to slightly yellowish, almost odorless liquid and chemically belongs to the group of adipates . It has a viscosity of ~ 13 m Pa · s at 20 ° C.

DEHA is almost insoluble in water, the solubility limits are stated differently. Felder et al. (1986) gives the solubility in deionized water as 0.78 ± 0.16 mg / L, this value has been cited many times. In organic solvents, such as. B. tetrachloroethane, ethanol, toluene, acetone, diethyl ether or methyl ethyl ketone, on the other hand, DEHA is readily soluble.

use

Diethylhexyl adipate is used in the production of plasticizers , cold-elastic soft PVC, rubber and cold-resistant and light-resistant nitro lacquers . It serves as a cold-resistant plasticizer in PVC films for food packaging or is used in conjunction with other plasticizers to improve the behavior at low temperatures in hoses, cables, films, etc.

Due to its solubility in oils and fats, diethylhexyl adipate migrates from food packaging and can thus be found in many foods (e.g. cheese). A maximum level of 18 mg / kg is permitted in food.

toxicology

DEHA is not classified according to the CLP Regulation No. 1272/2008 and does not require labeling.

Toxicokinetics

After absorption of DEHA, rapid distribution in the organism could be demonstrated in test animals. Depending on the type of administration, the highest concentrations were measured in adipose tissue, the liver or the kidneys after a maximum of 12 hours. Most of the elimination took place within the first 24 hours with the urine.

According to kinetic studies on rodents, DEHA is hydrolytically split up in the digestive tract, mainly into monoesters, 2-ethylhexanol and adipic acid. The hydrolysis products are quickly and almost completely absorbed. The main metabolites excreted in the urine of rats after oral administration are adipic acid, 2-ethyl-1,6hexanedioic acid, 2-ethyl-5-hydroxyhexanoic acid, 2-ethylhexanoic acid glucuronide and 2-ethylhexanoic acid glucuronide.

Exposure

It is known from various studies that DEHA can migrate from plastic packaging into food. This migration is higher, the higher the fat content of the food. In Great Britain, for example, DEHA could be found in all foods packed in PVC film in 1998.

Diethylhexyl adipate and its breakdown products can be detected in many bodies of water, soils and also in the air. In 2007, for example, DEHA and the breakdown products 2-ethylhexanal (2-EH), 2-ethylhexanol and 2-ethylhexanoic acid were detected in the sewage sludge of some sewage treatment plants in Canada.

acute toxicity

DEHA has a very low risk potential and is considered to be of low acute toxicity in the case of oral, dermal and inhalation exposure.

Awareness

DEHA is not sensitizing.

Animal studies have not found any skin sensitizing properties in patch tests with rabbits.

Risk assessment

Diethylhexyl adipate is one of the chemical substances that are produced in large quantities (" High Production Volume Chemical ", HPVC) and for which the Organization for Economic Cooperation and Development (OECD) collects data on possible hazards (" Screening Information Dataset ", SIDS ) was made.

Diethylhexyl adipate was included in the EU's ongoing action plan ( CoRAP ) in 2013 in accordance with Regulation (EC) No. 1907/2006 (REACH) as part of substance evaluation . The effects of the substance on human health and the environment are re-evaluated and, if necessary, follow-up measures are initiated. The reasons for the uptake of diethylhexyl adipate were concerns about consumer use , high (aggregated) tonnage and widespread use, as well as the dangers arising from a possible assignment to the group of CMR substances. The re-evaluation should be carried out by Finland from 2020 .

See also

• Diisononyl adipate

Individual evidence

1. ↑ Entry on DIETHYLHEXYL ADIPATE in the CosIng database of the EU Commission, accessed on January 14, 2020.
2. ↑ ^{a b c d e f g h i j} Entry on bis (2-ethylhexyl) adipate in the GESTIS substance database of the IFA , accessed on November 17, 2019(JavaScript required) .
3. ↑ expertsforadditives.com: Technical information Adimoll DO ( Memento of September 27, 2007 in the Internet Archive )
4. ↑ ^{a b c d e f g h i} Advisory Committee for Environmentally Relevant Existing Substances (BUA) of the German Chemical Society: Di- (2-ethylhexyl) adipate . Status: August 1996 edition. Hirzel Wissenschaftliche Verlagsgesellschaft, Stuttgart 1997, ISBN 3-7776-0759-2 .
5. ↑ ^{a b} Opresko, DM: Draft Report. Diethylhexyl Adipate - 103-23-1 . In: United States Environmental Protection Agency, Office of Toxic Substances (Ed.): Chemical Hazard Information Profile . Washington DC 1984.
6. ↑ ^{a b} World Health Organization: Di (2-ethylhexyl) adipate in Drinking-water . In: WHO Guidelines for Drinking-water Quality . 2004, p. 14 ( who.int [PDF]).
7. ↑ greenpeace.at: Diethylhexyl adipate - DEHA: Plasticizers in PVC films for food packaging ( Memento from January 5, 2016 in the Internet Archive ), 1999.
8. ↑ BASF: Technical data sheet Plastomoll DOA ( Memento from September 30, 2007 in the Internet Archive )
9. ↑ food-monitor.de: Softener: Cover closed, monkey dead , January 2, 2006, accessed on January 4, 2014.
10. ↑ ^{a b c} Registration dossier on bis (2-ethylhexyl) adipate ( Toxicological Summary section ) at the European Chemicals Agency (ECHA), accessed on November 17, 2019.
11. ↑ MC Cornu, Y. Keith, CR Elcombe, JC Lhuguenot: In Vivo and In Vitro Metabolism of Di- (2-ethylhexyl) Adipate a Peroxisome Proliferator, in the Rat . In: The Target Organ and the Toxic Process . tape 12 . Springer Berlin Heidelberg, Berlin, Heidelberg 1988, ISBN 978-3-540-18512-3 , pp. 265-268 , doi : 10.1007 / 978-3-642-73113-6_43 .
12. ↑ YES Nicell, DG Cooper, S. Barnabé, I. Beauchesne: Plasticizers and related toxic degradation products in wastewater sludges . In: Water Science and Technology . tape 57 , no. 3 , February 1, 2008, p. 367–374 , doi : 10.2166 / wst.2008.001 .
13. ↑ MALLETTE FS, OF HAAM E .: Studies on the toxicity and skin effects of compounds used in the rubber and plastics industries. II. Plasticizers. No. 6 (3) . AMA Arch Ind Hyg Occup Med., September 1952, p. 231-6 , PMID 14952047 .
14. ↑ OECD : Screening Information Dataset (SIDS) Initial Assessment Report (SIAR) for Bis (2-ethylhexyl) adipate , accessed on October 3, 2014.
15. ↑ Community rolling action plan ( CoRAP ) of the European Chemicals Agency (ECHA): Bis (2-ethylhexyl) adipate , accessed on March 26, 2019.