Non-Targeted Screening And Risk Assessment For Migrants From Biodegradable PBAT/Modified Starch Food Contact Plastic

BackgroundIn the process of food circulation,food contact materials have various functions such as protecting food from external contamination,facilitating storage and transportation,and promoting sales.However,with food contact,the migration of substances in food contact materials to food has become one of the important sources of food contaminants.The safety problems caused by the migration of food contact materials have become a hot spot in food safety,Plastics are widely used in food contact materials due to their superior mechanical properties,barrier properties,and thermoplastic molding properties,but non-biodegradable plastics have caused serious environmental pollution problems.With the development of biodegradable plastics,biodegradable plastics have been gradually applied in food packaging as food packaging materials.However,biodegradable food contact plastics may contain more migrations than non-biodegradable plastics.Moreover,biodegradable food contact plastics are usually blended with plant fibers(such as lignin,bamboo powder,starch,etc.)to improve their mechanical property,which may be caused more migrations,some of which have potential health risks.As a widely used biodegradable polybutylene terephthalate-co-terephthalate(PBAT)/modified starch(MS)food contact plastic,its potential risks remain to be further clarified.Objective1.Building a database of biodegradable food contact plastics to support the nontargeted screening of migrations in PBAT/MS food contact plastics.2.Non-targeted screening of migrations and non-intentionally added substances in PBAT/MS food contact plastics to identify potential risk factors.3.Based on the risk matrix classification model,the risk classification of the identified potential risk factors in PBAT/MS food contact plastics were realized,and the scientific basis for formulating corresponding control measures is provided to ensure the safety of PBAT/MS food contact plastics.MethodsTaking the raw materials,blended pellets and finished products of PBAT/MS food-contact plastics as the research objects,the research results in 3%acetic acid(w/v),4%acetic acid(w/v),10%ethanol(w/v),20%ethanol(w/v),50%ethanol(w/v)and 95%ethanol(w/v)migration in 6 different food simulants.To gain new knowledge on the safety of thses food contact materials,which will finally contribute to saferdegradable materials.1.The physicochemical and pharmaceutical information was collected by using Python and QSAR software.To integrate a database of extractable and leachables from biodegradable plastics for food contact.2.A high-throughput non-targeted screening method was developed based on chromatography-high resolution mass spectrometry(HRMS)equipment to identify the migration and non-intentionally added substances of PBAT/MS food contact plastics in different food simulants and perform semi-quantitative analysis.3.In vitro biological tests were used to study the cytotoxicity and mutagenicity of migrations from PBAT/MS.Combined with the database and risk matrix classification model constructed above,the preliminary risk assessment of PBAT/MS plastic for food contact was realized.Results1.Through literature research,database related to extractables and leachables of biodegradable plastics for food contact was constructed,which containing physicochemical and toxicological information.The constructed risk matrix classification method was used to classify the mutagenicity risks of 627 migrations,so as to quickly identify the substances,which should be given priority attention.2.Based on high-resolution mass spectrometry,high-throughput non-targeted screening of food contact material migrations were realized by using the "forest ion peak".For the migration of PBAT/MS food contact plastics in 6 different food simulants,a total of 16 volatile migrations,131 non-volatile migrations,and 147 migrations were screened and identified.Among them,the main by-products formed in the production and processing process and the contaminants such as mycotoxins and pesticide residues that are unintentionally brought into the blending of modified starch.3.The results of the cytotoxicity test and the Salmonella typhimurium reverse mutation(Ames)test showed that the migration of PBAT/MS food contact plastics in different food simulants was not cytotoxic and mutagenic under the assumption of high exposure scenarios.Combined with the toxicological assessment and risk classification results of QSAR,pesticide residue contamination,adhesives and lubricants are the migratory substances that should be prioritized for PBAT/MS food contact plastics.ConclusionCombined with the risk classification results and in vitro biological test results,PBAT/modified starch materials as food contact materials have a low risk.However,high attention should be paid to the potential risks of pesticides and mycotoxins introduced by the blending of modified starch.