German researchers claim plasticisers in food packaging causes weight gain

In a study it tested Di-(2-ethylhexyl)-phthalate (DEHP), claiming humans are exposed to these compounds through ingestion, inhalation and dermal exposure and by leaching from food packaging materials.

Caloric intake, high fat diets, low physical activity

According to co-author, Martin von Bergen, UFZ, obesity is the fastest growing health problem in Europe and worldwide. Being overweight affects between 30% and 80% of adults in the WHO (World Health Organisation) European Region and up to one third of children.

In addition to genetic factors, life style factors such as excessive caloric intake, high fat diets, and low physical activity contribute to obesity. However, there is also increasing evidence that environmental pollutants including endocrine-disrupting chemicals may contribute to the development of obesity and metabolic disorders.

Chronic exposure to endocrine-disrupting chemicals such as dioxins bisphenol A or phthalates has been linked to an increased risk of developing insulin resistance or diabetes.

“We therefore tested the hypothesis that chronic DEHP exposure causes impaired insulin sensitivity, affects body weight, adipose tissue (AT) function and circulating metabolic parameters of obesity resistant 129S6 mice in vivo​,” said von Bergen .

“An obesity-resistant mouse model was chosen to reduce a potential obesity bias of DEHP effects on metabolic parameters and AT function.The metabolic effects of 10-weeks exposure to DEHP were tested by insulin tolerance tests and quantitative assessment of 183 metabolites in mice​.

“Furthermore, 3T3-L1 cells were cultured with DEHP for two days, differentiated into mature adipocytes in which the effects on insulin stimulated glucose and palmitate uptake, lipid content as well as on mRNA/protein expression of key adipocyte genes were investigated​.

“We observed in female mice DEHP treatment causes enhanced weight gain, fat mass, impaired insulin tolerance, changes in circulating adiponectin and adipose tissue Pparg, adiponectin and estrogen expression​.”

Chronic DEHP treatment causes increased body weight

How plasticisers actually change hormonal balance and cause weight gain is still unclear but the report concluded its data provides evidence that chronic DEHP treatment causes increased body weight, fat mass and altered serum metabolites in a gender specific manner, which could be mediated by a DEHP-induced increase in estrogen receptor expression and reduced Pparg expression in adipose tissue.

Although, DEHP treatment led to significantly impaired insulin tolerance, it did not affect glucose tolerance, HOMA-IR, fasting glucose, insulin or triglyceride serum concentrations. This may suggest that DEHP treatment does not cause impaired glucose metabolism at the whole body level.

Plasticisers are added to food packaging and various other products to make them more flexible and easier to handle. They can enter the body through the skin or in food, where they can disrupt hormone production.

Fatty foods are particularly prone to this, as the plasticisers dissolve easily and migrate into the food.

Von Bergen said he and his colleagues now want to investigate their effect on the development of early childhood diseases. The results are intended to help carry out risk assessments on hormone-disrupting chemicals, by both German and European authorities.

European Parliament Food Contact Materials workshop

At The European Parliament ‘Food Contact Materials’ workshop today (January 26) HEAL (Health and Environment Alliance) is calling for proper regulation of all types of ‘Food Contact Materials’, including a prohibition on the use of both endocrine disrupting chemicals and “Substances of Very High Concern”, or SVHCs, as defined under REACH chemical regulation.

“Current EU legislation of food contact materials is not fit for its purpose of protecting public health. It permits chemicals that are prohibited in other products under other EU law. Equally worrying is the fact that it ignores today’s science on endocrine disrupting chemicals,” said ​Lisette van Vliet, HEAL’s senior policy adviser, HEAL.

Concerns about plastics leaching into food from packaging has already led to an EU ban on Bisphenol A (BPA) in baby bottles and limitations on the use of certain phthalates in food contact materials made of plastic. Both these substances are known to be endocrine disruptors.

Chemicals in any material that come into contact with food can leach into food or drink. This migration depends on how hot the material becomes, on the length of time the food is in contact with the material, the proportion of the food in contact with the material, and the food chemistry (chemicals migrate more into fatty and acidic foods, for example).

Source​: PLOS​ (Public Library of Science)

Title: ​Di-(2-Ethylhexyl)-Phthalate (DEHP) Causes Impaired Adipocyte Function and Alters Serum Metabolites

Author(s):​ Nora Klöting; Nico Hesselbarth; Martin Gericke; Anne Kunath; Ronald Biemann; Rima Chakaroun; Joanna Kosacka; Peter Kovacs; Matthias Kern; Michael Stumvoll; Bernd Fischer; Ulrike Rolle-Kampczyk; Ralph Feltens; Wolfgang Otto; Dirk K. Wissenbach; Martin von Bergen; Matthias Blüher.

Published:​ December 2, 2015

DOI: ​10.1371/journal.pone.0143190