Diisobutyl phthalate

DiBP; Phthalic acid diisobutyl ester; formula: C16H22O4 oder C6H4(COOCH2CH(CH3)2)2; CAS Registry Number: 84-69-5
Structure of diisobutyl phthalate
Source: PubChem

Short-chain phthalate whose use in packaging materials for food has been withdrawn voluntarily by the industry in 2007

Diisobutyl phthalate (DiBP) is synthesized by chemical reaction of phthalic acid with iso-butyl alcohol.
DiBP is a plasticizer with coagulating properties which was used with different polymers, e.g. poly acrylate, poly acetate dispersions, cellulose acetate, cellulose nitrate, ethyl cellulose, polyurethane, and polyvinyl butyrate. In combination with other plasticizers it was applied as gellant in processing of so-called plastisols. DiBP is present for instance in floorings, adhesives, lacquers, inks, hydraulic fluids and lubricants. It was used as marker in fuels for tax purposes and also in the production of titanium catalysers.
DiBP can substitute dibutyl phthalate (DBP) in most, if not all, applications.
Since DiBP is not chemically bound in the polymer matrix it may outgas or be released upon contact with fluids and fat. In the environment DiBP is degraded relatively fast.
It is toxic to aquatic organisms and may cause long-term adverse effects in the aquatic environment.
In animal experiments DiBP is toxic to reproduction and development.

DiBP in adhesives used for paper and packing may contaminate recycled paper and board packaging as used for instance for foodstuffs. From there DiBP has been found to migrate into food.
In 2007, the producers of adhesives and the manufacturers and processors of paper, cardboard and paperboard have committed themselves to a voluntary negotiated agreement to reduce production and use of DiBP-containing adhesives. Since 2015 the general use of DiBP without special authorization is prohibited in the EU.

For the Environmental Specimen Bank not the parent compound DiBP itself is analysed in human specimens but its major metabolites.

Substances

MiBP Mono-iso-butylphthalate is the primary metabolite of DiBP resulting from the elimination of one iso-butyl group.
OH-MiBP

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 - 2015