"Plasticisers – Boys poisoned," screamed a headline that appeared in the German news magazine "Focus" on 5 December 2005. Apparently, boys of kindergarten age are heavily contaminated with the chemical DEHP, said the report, referring to a study from the German Federal Environmental Agency (UBA; www.uba.de). The UBA was said to suspect that the main source of the contamination is food: "Boys probably eat more meat, and that frequently comes from packaging containing DEHP," was the appraisal of the "experts" quoted.

Plastics industry professionals shake their heads in frustration when reading the pseudo-scientific reports on polymers and their additives that appear often, even in serious publications. It is true that cling film made of plasticised PVC is used for packaging fresh meat in supermarkets. Because of its controlled oxygen diffusion, it ensures that the meat looks fresh longer. However, DEHP (diethylhexylphthalate) is never used as a plasticiser in these films, but rather DEHA (diethylhexyladipate). Often abbreviated also as DOA, this chemical is explicitly included in the positive list of the European Directive 2002/72/EC appendix III B – plastics and articles intended for food-contact applications.

Migration depends on application and contact medium
Plasticisers long have been in the firing line of campaigns launched by environmentalist organisations such Greenpeace to target PVC as being hazardous. According to the European Council for Plasticisers and Intermediates (Brussels / Belgium; www.plasticisers.org), 95% of all plasticisers go into PVC, to make the otherwise brittle material more flexible, more durable and easier to handle. A number of professional and trade organisations provide literature on the safety of plasticisers. Most of the websites listed in this article give overviews in English. One of these is the brochure "Plastics and Plasticisers" (status June 2004).

Plasticised PVC (P-PVC) is used in many consumer products, including floor coverings, wallpaper, infusion tubes and dashboard coatings. The higher the added quantity – which may be up to 50% by weight – the lower the shore hardness of the plastic. This works because the plasticiser molecules are not chemically bound to the molecules of the polymer. Plasticisers can migrate out of the polymer matrix, however. Because they are highly lipophilic (fat-loving), migration can be a problem in particular when the plastic comes in contact with foods containing fat.

There are permissible thresholds, known as "specific migration limits," for this migration. These regulate how much plasticiser may migrate into one kilogramme of food. For fresh meat, the threshold is 22 mg/kg, for foods containing fat it is 18 mg/kg. DEHA´s migration rate is around 5 mg/kg. The toxicological effects of plasticisers on human health, especially with foodstuffs, are evaluated by the Federal Institute for Risk Assessment (Berlin, Germany; www.bfr.bund.de). One of the latest examples, dating from October 2005, is the evaluation entitled Migration of phthalates from twist-off lids into foodstuffs.

Evaluation of phthalates and their substitution
Plasticisers can migrate not only into foodstuffs, but also into pharmaceuticals and enteral nutrient solutions administered to patients via infusions. Evaluations here are done mostly by the Federal Institute for Drugs and Medical Devices (BfArM, Bonn / Germany; www.bfarm.de). In January 2005, the agency organised a meeting of experts on the subject of DEHP in medical products. The results show a unanimous assessment, that exposure to DEHP through medical products should be minimised as a precaution, while maintaining the quality of medical care. This, the panel said, should apply especially to risk groups, including all children, from newborn infants to the end of puberty, as well as pregnant women and nursing mothers.

At its meeting on 2 December 2005, the EU Council of Ministers passed a draft directive aimed at banning phthalate plasticisers completely from children´s toys and products for babies – see Plasteurope.com Web of 07.07.2005 203145. The table below summarises the toxicological and ecological concerns regarding the most important plasticiser groups.

As phthalates often fail health risk assessments, they are increasingly being substituted by phthalate-free plasticisers based on adipates (such as DEHA), citrates and substances from renewable raw materials such as sebacic acid esters, even if these are often more expensive. Some chemicals and plastics producers already have commercially available plasticisers. "Hexamoll DINCH" made by BASF (Ludwigshafen / Germany; www.basf.com) was named as a positive example as regards the migration of plasticiser from PVC infusion tubes into enteral nutrient solutions in a development report by Germany´s Fraunhofer IVV (Freising; www.ivv.fgh.de).

Evaluation of plasticisers in Europe
Abbr.	Name	Reproduction	Embryo	Environment	Toys	Food	Med
BBP	Butylbenzylphthalate	o	oo	oo	x	-	-
DBP	Di-n-butylphthalate	o	oo	oo	x	-	-
DEHA	Di-(2-ethylhexyl)adipate	-	-	-	-	++	-
DEHP	Di-(2-ethylhexyl)phthalate	o	oo	-	x	-	+
DIDP	Diisodecylphthalate	-	-	-	x	-	-
DINP	Diisonoylphthalate	-	-	-	x	-	-
DNOP	Di-n-octylphthalate	-	-	-	x	-	-
DINCH	Diisononyl-1,2-cyclohexanedicarboxylate	-	-	-	++	++	-

o = may impair, oo = may damage, x = ban / partial ban planned, + = specific formulation, ++ = recommmended for use

Sources: PlasticsEurope Deutschland, BfR, 2002/72/EC, European Pharmacopoeia

Phthalate substitutes becoming more competitive
Around 830,000 tonnes of plasticisers were used in the EU in 2004. In 2003, the figure was 850,000 t, and in 2002, 840,000 t. These figures illustrate that plasticiser demand in Europe is declining only slightly. The additives are not imported into the EU as such, but are integrated in the finished products, for example in toys.

Market experts at Ceresana (Konstanz / Germany; www.ceresana.com) estimate global consumption of plasticisers in 2004 at around 5.5m t, valued at more than EUR 7 bn. Market prices of the standard types currently stand at EUR 900-1,300/t, according to PIE´s research. Only two years ago, converters were paying only half that. Prices of the innovative, eco-efficient substitutes, on the other hand, have remained stable, as they have become increasingly competitive.

e-Service:
Positive list of European Directive 21002/72/EC Attachment IIIB – Plastics and articles that come in contact with food, as PDF document (358 KB)
Development report "Migration of Plasticisers from PVC tubes in Enteral Nutrient Solutions" from Fraunhofer IVV, as PDF document (87 KB)