In a review article published on March 29, 2023, in the journal Comprehensive Reviews in Food Science and Food Safety, Júlia Moraes da Costa from the Federal University of Rio de Janeiro, Brazil, and co-authors summarized the scientific knowledge on the presence of phthalate acid esters (PAEs) in different types of foods as well as discussed their sources and potential risks. To this aim, the scientists systematically searched Science Direct, PubMed, Web of Science, and Scopus using predefined search terms and included the 22 studies which met their eligibility criteria in their review.
Da Costa and co-authors collected data on 19 PAEs which were found to occur in a wide range of food types including dairy products, meat, cereals, fruits and vegetables, and baby foods. Bis(2-ethylhexyl)phthalate (DEHP, CAS 117-81-7) had the highest abundance and exceeded its specific migration limit of 1.5 mg/kg in many types of foods. In addition to DEHP, dibutyl phthalate (DBP, CAS 84-74-2), benzylbutyl phthalate (BBP, CAS 85 68 7), diisononyl phthalate (DINP, CAS 28553-12-0), and diisodecyl phthalate (DIDP, CAS 26761-40-0) were among the identified PAEs. “The risk of exceeding the tolerable daily intake (TDI) was high for DEHP and DBP in fish, fat and oils, cereals, and milk and dairy products for children and adults. Fat and oils are the most critical food for DEHP, DBP, BBP, and DINP.” The highest concentration of an individual PAE in one product was DEP in a lettuce bag (16.5 mg/kg).
The authors further reported that 14 of the PAEs detected in foodstuffs are not authorized by Commission Regulation (EU) No. 10/2011 for their use in food contact. As a source of contamination, the researchers summarized that it “can occur during food processing through contact with tubes and conveyor belts, and it is accentuated in an acidic medium and varies in other pH ranges.” Moreover, migration is higher into fatty foods and increases with contact time and temperature. Previous studies have found that regularly consuming takeaway food increases phthalate exposure (FPF reported).
Da Costa and co-authors recommended using stainless steel and other additive-free materials for food processing and using natural plasticizer to replace PAEs in necessary plastic packaging. In the search for alternatives regrettable substitutions must be avoided. For instance, non-phthalate alternative plasticizers have been found to have the potential for thyroid hormone disruption (FPF reported). Generally, phthalates have been linked to several health impacts, including the deterioration of semen quality (FPF reported) and leiomyoma growth (FPF reported). A report published in March 2023, summarized the health effects of plastic chemicals including phthalates (FPF reported) and a review in 2021 that examined 38 human health studies concluded that regulatory ‘safe’ limits for human exposure to phthalates may be set at levels not sufficiently protective of human health (FPF reported).
In an article published on March 5, 2023, in the journal Foods, Salvatore Velotto from the University of Study of Roma, Italy, and co-authors investigated the presence of the two phthalates, DEHP and DBP, in coffee powder and beverages. The researchers acquired 60 samples of coffee powder and beans in Naples, Italy, of which 30 were packaged in multilayer bags, 15 in aluminum tin, and 15 were coffee paper pods. To not only compare how different packaging materials affect the concentrations of the analytes but also the effects of the brewing process, they prepared each coffee with a professional espresso machine, a moka pot, and a home espresso machine (10 samples each). DEHP and DBP levels were measured with gas chromatography-mass spectroscopy (GC-MS).
Median concentrations of DBP and DEHP were 0.303 and 5.014 ng/g food for the multilayer packaging samples, 0.578 and 4.921 ng/g food for the aluminum packaged samples, and 0.226 and 3.857 ng/g food for the paper pods. Accordingly, no significant difference was observed between the different packaging materials. However, the coffee machine affected the DEHP concentration in the brewed coffee: concentrations were higher when using a professional espresso machine (2.58-21.32 ng/g beverage compared to the other machines (< LOD-2.41 ng/g Moka pot, < LOD-2.98 ng/g home espresso machine). Furthermore, “higher DEHP levels [were detected] in coffee beverages than in coffee powder [which] may be due to its leaching through machine components.” Assessing the risk of consuming one to six cups of coffee/per day showed that “exposure to DEHP and DBP through consumption of each type of coffee was well below the tolerable daily intake.” Phthalates have previously been detected in decaffeinated coffee samples in concentrations between 29.3 and 734 ng/capsule (FPF reported).
Hongly Tan and co-authors from Jinan University, Guangzhou, China, screened baby foods for plastic additives including PAE. In their article published on March 10, 2023, in the journal Environmental Science & Technology Letters, they described that they purchased 70 baby food samples (20 baby formulas, 30 cereal products, 11 fruit or vegetable puree products, and nine meat products) in supermarkets or online.
They extracted baby formula with acetonitrile under ultrasonication for 15 min while (semi)solid foods were first ground to powder and mixed with hexane and dichloromethane before undergoing the same extraction procedure. Using ultraperformance liquid chromatography quadrupole MS and their in-house plastic additive analytical database, the scientists analyzed the samples for 245 chemicals which they grouped based on their molecular structure: PAE (41 chemicals), non-PAE plasticizers (NPPs; 46), organophosphate esters (OPEs; 48), synthetic antioxidants (SAOs; 49), UV stabilizers (UVs; 41), bisphenol analogs (BPs, 14), and parabens (6).
The authors detected 47 of the 245 plastic additives in more than half of the samples and another 87 “sporadically.” Median total concentrations for the seven groups were 46.1 ng/g (PAEs), 52.7 (NPPs), 8.20 (OPEs), 8.15 (SAOs), 1.56 (UV-stabilizers), 0.51 (BPs), and 0.04 ng/g (parabens). In total, the targeted analytes’ concentrations ranged from 3.86 to 9580 ng/g food. This shows that “despite the threat of environmental and health concerns for decades, PAEs remained relatively abundant in baby foods.”
The concentration and abundance of non-phthalate plasticizers were even higher than that of phthalate esters and some of them have for the first time been detected in baby foods. The authors emphasized that the non-phthalate plasticizers that often replace PAEs “may produce comparable or even greater contamination in food items” and although data on their toxicological impacts remains lacking.
Based on their results, Tan and co-authors also estimated dietary intake of plastic additives via infant formula or supplementary foods. For infants, the intake via formula was estimated to be 69.1 ng/kg body weight (bw) and via supplementary food 5930 ng/kg bw, respective numbers for toddlers were 65.8 and 6490 ng/kg bw. The researchers consider that “a low risk of dietary exposure. However, the high complexity of plastic additives detected in baby foods raises concern about the exposure to an increasing list of industrial chemicals, due to potential cocktail effects, limited knowledge of biological effects of emerging substances, and exposure from additional sources.”
References
De Costa, J. M. et al. (2023). “Occurrence of phthalates in different food matrices: A systematic review of the main sources of contamination and potential risks.” Comprehensive Reviews in Food Science and Food Safety. DOI: 10.1111/1541-4337.13140
Tan, H. et al. (2023). “Contamination of Baby Foods by Plastic Additives: A Pilot Screening Study.” Environmental Science & Technology Letters. DOI: 10.1021/acs.estlett.3c00100
Valetto, S. et al. (2023). “Occurrence of Phthalate Esters in Coffee and Risk Assessment.” Foods. DOI: 10.3390/foods12051106
