Non-targeted screening for contaminants derived from food contact water-borne coatings and risk assessment based on (Q)SAR matrix

Because of great knowledge gaps between toxicological data and chemical constituents for substances involved, water-borne coating paper and board have emerged as a sort of particular concern for the safety of consumers. Herein, we describe a step-by-step method including extraction, gas chromatography-mass spectrometry (GC -MS) fractionation, tentative identification of related substances and risk assessment of chosen tentatively iden-tified substances based on (Quantitative) Structure-Activity Relationships ((Q)SARs) matrix. Three water-borne coating samples possessing different compositions were investigated. Polyacrylates were first determined as the possible compositions of coating samples based on Fourier transform infrared spectrophotometer (FTIR) and differential scanning calorimetry (DSC) analysis. 7 out of 23 elemental compositions determined by inductively coupled plasma emission spectrometry (ICP-OES) were demonstrated for peaks over a specific migration limit evidencing the likely heavy metal contamination from water-borne coatings. Of 359 tentatively identified sub-stances, 85 and 38 substances were assigned to Hazard IV and Risk IV, respectively, disclosing the particular concern for consumer safety, which may originate from decomposition products and impurities from industrial processing. Overall, understanding the identity of contaminant will allow it easier to find the possible source, and to study which part of the water-borne coating paper-producing process that could be amended to mitigate the risk.

Automated summary

Due to a lack of knowledge about toxicological data and chemical constituents, water-borne coating paper and board are a particular concern for consumer safety. This study presents a step-by-step method for extraction, gas chromatography-mass spectrometry (GC-MS) fractionation, tentative identification, and risk assessment of substances in water-borne coatings. The results indicate the presence of heavy metal contamination, likely from decomposition products and impurities in industrial processing, posing a risk to consumers. Understanding the identity of contaminants can aid in finding the source and improving the production process to mitigate the risk.