Feica: Risk assessment of cyclic esters in polyester adhesives
Feica, the Association of the European Adhesive and Sealant Industry, has published a Summary Report of a Feica risk assessment carried out on cyclic esters potentially present in polyester adhesives intended to be used in food contact materials.
The document aims to provide the necessary information to help downstream users carry out their own risk assessments. The summary report intends to outline the main findings of the risk assessment and explain that human exposure to cyclic esters from polyester pre-polymers in food packaging adhesives is not relevant from a toxicological point of view.
Cyclic esters are of interest in food contact applications because small quantities of non-reactive cyclic esters are created as by-products alongside the high molecular weight chain polyesters used in the manufacture of laminating adhesives intended for use in food contact applications. In the European Union, all polyesters used for this purpose shall be based on monomers authorised to be used in plastic materials and articles intended to come into contact with foodstuffs according to the Plastics Regulation (EU) No. 10/2011.
Whilst the long-chain polymers of the polyester do not have a migration potential, the smaller cyclic esters could potentially migrate into the food. These cyclic esters are non-intentionally added substances (NIAS) and therefore require a risk assessment. EFSA’s Note for guidance for petitioners states that migratable substances from food packaging with a molecular weight of less than 1000 Da are important from the toxicological point of view as they could be absorbed in the gastrointestinal tract.
Feica created a Cyclic Esters Task Force comprising several member companies – including Henkel, Dow, Coim, H.B. Fuller, and Bostik – who shared study results and expertise with the aim of developing a risk assessment document to assist downstream users in their risk assessments. ChemSafe, an independent consulting company, facilitated the sharing of data and the development of a common risk assessment. The available data suggest the human exposure to cyclic esters representing NIAS from polyester pre-polymers in adhesives in food packaging applications does not present a risk to consumers. Attention should be paid to food packaging systems that generate cyclic esters containing ortho-phthalic acids because they don’t seem to hydrolyse and exposure to these NIAS could be different than to other cyclic esters since they exhibited different behaviour in the above mentioned studies.
On 4 June 2020, Feica organised a webinar on a Feica risk assessment for cyclic esters, which was attended by more than 100 registrants. Dr. Matthias Frischmann, food chemist and Head of Corporate Analytics at Henkel in Düsseldorf, Germany, introduced the topic of cyclic esters, explained the risk assessment that was carried out and the responsibilities of each actor in the supply chain of polyurethane and heat seal adhesives.
Feica Executive Director Regulatory Affairs Jana Cohrs - Rahmoun stated, “More investigation is needed to better understand the impact of ortho-phthalic esters from food packaging. The Summary Report is based on the current state of knowledge. Further evaluation will be possible in the case that new data becomes available. In the meantime, Feica hopes that the document will assist downstream users in their risk assessment activities.”