Phthalates and substitutes

Phthalate diesters

General-purpose plasticizers for PVC and other polymers

Phthalates are esters of phthalic acid (1,2-benzenedicarboxylic acid) with different alcohols. They are mainly used in the production of polyvinyl chloride to soften the PVC. Plasticized PVC is used in numerous applications such as wire insulations, floor tiles and carpets, wall papers, foils, synthetic leather, packaging, medical products (e.g. blood bags and flexible tubes), toys, childcare articles and sporting goods. The mean phthalate content of plasticized PVC is 30–35%. Phthalates are not chemically bound to PVC and may therefore outgas or be released upon contact with fluids and fat. Due to their wide use, phthalates are ubiquitous in the environment.
Released phthalates strongly adsorb to particles and may be subject to long-range transport in the atmosphere.
In soils and sediments phthalates are persistent. They have a high potential for bioaccumulation. Some phthalates are endocrine disruptors and are suspected to be toxic for reproduction and development.

Some phthalates have been forbidden in childcare articles and toys in the European Union (EU) since 2005. Since 2015, use of the phthalates DEHP (bis(2-ethylhexyl)phthalate), DBP (dibutyl phthalate), BBP (benzyl butyl phthalate), DINP (di-isononyl phthalate), DIDP (di-isodecyl phthalate) and DNOP (di-n-octyl phthalate) is prohibited without a specific authorisation.

Due to the strong regulation, the alternative use of long chained phthalates and different substance classes is on the rise. Hexamoll® DINCH® (Diisononyl cyclohexane-1,2-dicarboxylate) is an example of these substitute plasticizers.

The above mentioned substances are degraded when entering the body. Therefore only their degradation products (metabolites) can be analysed. The first metabolites are monoesters which are further degraded to other metabolites.

Recommended analysis examples

Sub-groups

Dimethyl phthalate Short-chain phthalate
Diethyl phthalate Short-chain phthalate
Di-n-butyl phthalate Short-chain phthalate
Diisobutyl phthalate Short-chain phthalate whose use in packaging materials for food has been withdrawn voluntarily by the industry in 2007
Di-n-pentyl phthalate A phthalate, which might soon be subject to more severe regulation
Dicyclohexyl phthalate Phthalate with two cyclohexane rings as ester rests
Di-n-octyl phthalate Structural isomer of DEHP
Diethylhexyl phthalate Formerly the world's most important plasticizer among the chemical group of phthalates
Diisononyl phthalate Mixture of phthalate diesters differing slightly in branching of the alcohol chains and main substitute of DEHP as plasticizer
Di(2-propylheptyl)phthalate (DPHP) Analytically difficult to grasp
Butylbenzyl phthalate Only phthalate of commercial importance with differing side chains, one of them representing a benzyl group
Hexamoll® DINCH® Important substitute for phthalates

Specimen

Students Student groups with an even number of female and male students at the age of 20 to 29.

Sampling area

Sampling sites (humans) 4 university cities as sampling areas.

Sampling period

1988 - 2017

Extended information

Links to external information and legislation

Literature