Influence of UV light, ultrasound, and heat treatment on the migration of bisphenol A from polyethylene terephthalate bottle into the food simulant

This research examined the impacts of ultrasound, UV light, storage time, and temperature on the leaching of bisphenol A (BPA) from polyethylene terephthalate (PET) drinking water bottles in Turkey. The initial phase of the investigation encompassed the quantification of BPA in two distinct brands of bottled water. Samples were extracted by solid- phase extraction (SPE) and analyzed by high performance liquid chromatography with fluorescence detection (HPLC-FLD). According to the results in the first part, the highest BPA levels were found in bottled water. In the second part of the study, 10 to 30 min of ultrasound treatment increased the BPA migration with increased time in simulants. In the first and second weeks of storage at 25 °C, the effect of storage on BPA migration was below the detection limit ( Collapse

Key Words

• Bisphenol A
• Food Simulants
• HPLC-FLD
• PET bottles
• UV light
• Ultrasound

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MESH Headings

• Polyethylene Terephthalates/chemistry
• Hot Temperature
• Drinking Water/analysis
• Ultraviolet Rays
• Food Contamination/analysis
• Benzhydryl Compounds/analysis
• Food Packaging

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Grants Collapse

Affiliation(s)

Zana M Abdulazeez Department of Food Science and Quality Control, Faculty of Agricultural Engineering Sciences, University of Sulaimani, Iraq.
Fehmi Yazici Department of Food Engineering, Faculty of Engineering, Ondokuz Mayis University, Samsun, Turkey
Abdurrahman Aksoy Department of Pharmacology and Toxicology, Faculty of Veterinary Medicine, Ondokuz Mayis University, Samsun, Turkey

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Beached plastic and other anthropogenic debris in the inner Seychelles islands: Results of a citizen science approach

Masses of plastic and other anthropogenic debris on beaches of inner Seychelles and derived from 53 organised clean-ups have been analysed. Debris and plastic densities ranged from 0.0011 to 0.1622 kg m-2 and 0.0004 to 0.1179 kg m-2, respectively, and data from successive cleans of the same beach resulted in respective median accumulation rates of 0.0293 and 0.0137 g m-2 d-1. There was no dependence of density or accumulation on beach location/aspect or season, but there were significant inverse relationships with beach area. This effect was attributed to most debris and plastic being trapped on the backshore by rocks and vegetation, and the areal proportion of backshore increasing with decreasing beach size. Plastic is derived from local littering and more distal sources, with polyethylene terephthalate bottles, flip-flops and Styrofoam fragments making important contributions. Without intervention and an increased risk of coastal flooding with climate change, beached debris on Seychelles is predicted to increase.

Production and characterisation of solid waste-derived fuel briquettes from mixed wood wastes and waste pet bottles

Wood waste and waste Polyethylene Terephthalate (PET) bottles are two of the solid wastes posing severe challenges to waste management facilities and constituting nuisance to humans and the environment in Nigeria due to poor management. These wastes could be utilized to produce solid biofuels for various energy applications to reduce CO2 emissions. This study, therefore, aims to investigate the potential of converting these wastes locally into solid waste-derived fuels (SWDF) briquettes in a bid to present an alternative approach to managing them. Four types of SWDF briquettes were produced from mixed wood waste and waste PET bottles in blend ratios of 100:0, 60:40, 50:50, and 40:60 using a screw press briquetting machine with single extrusion die. The effect of PET plastic amount on different properties, such as net calorific value, ash content, durability, and density, of the produced briquettes was investigated. In addition, obtained results were compared with the quality standards of densified fuels specified by the European Pellet Council. to ascertain the quality of the produced SWDF briquettes. The results revealed that the SWDF briquettes made only from mixed wood waste exhibited the lowest calorific value (17.15 MJ/kg) and highest ash content (2.74 %), while the SWDFs made from blends of mixed wood waste and PET bottles had higher calorific values (17.85-20.77 MJ/kg) and lower ash contents (1.05-1.37 %). Moreover, except for density and chlorine content (<750 kg/m3 and <0.03 wt% respectively), all the produced SWDFs complied with the quality standards of densified fuels specified by the European Pellet Council. These results suggest that these blends could yield SWDFs with improved quality and combustion properties, and could present a new way of managing these solid wastes.

An inevitable but underestimated photoaging behavior of plastic waste in the aquatic environment: Critical role of nitrate

Photoaging is an important reaction for waste plastics in the aquatic environment and plays a key role in the lifetime of plastics. Nevertheless, when natural photosensitive substances such as nitrate participate in this process, the physiochemical changes in plastics and the corresponding reaction mechanisms are not well-understood. In this work, the photochemical behavior of polyethylene terephthalate (PET) bottles in deionized water and nitrate solution was systematically investigated under ultraviolet (UV) irradiation. The analyses of the surface physicochemical properties of the photoaged PET bottles indicated that, after 20 days of photo-irradiation, the presence of nitrate reduced the contact angle from 69.8 ± 0.9° to 60.0 ± 0.3°, and increased the O/C ratio from 0.23 to 0.32, respectively. The leaching rate of dissolved organic carbon (DOC), which was 0.0193 mg g^-1·day^-1 in nitrate solution, was twice that of 0.00941 mg g^-1·day^-1 in deionized water. Furthermore, fluorescence spectroscopy revealed that the increasing DOC had aromatic rings with hydroxyl on the side-chain formed after UV irradiation. The positive effect of nitrate on the degradation of PET bottles was mainly through the generation of hydroxyl radicals that were produced through the photolysis of nitrate. In addition, two-dimensional correlation spectroscopy analysis showed that the chain scission of PET plastics could be initiated by nitrate-induced ·OH attacking the carbon-oxygen bonds instead of forming peroxides with oxygen. This work elucidates the mechanism of photodegradation of plastics that was induced by nitrate and highlights the important role of natural photosensitive substances in the photoaging process of plastics.

Determination of the composition and properties of PET bottles: Evidence of the empirical approach from Perm, Russia

Efficient collection systems and information about the characteristics and quality of collected secondary plastic waste flows are of fundamental importance for the development of circular economies. In order to assess the effectiveness of the implementation of separate collection systems for plastic packaging, especially polyethylene terephthalate (PET) bottles, characteristic of the collected PET bottles in street mesh containers were studied in the city of Perm, Russia. The share of extraneous fractions was assessed and differentiation was carried out by volume, type of product, label presence, shape, content of solid and liquid impurities and colour. These results indicate that PET composition in different seasons is very similar, despite the assumption that the consumption of PET bottles in the spring and autumn seasons varies. In the mesh containers, up to 34% of the items were foreign objects, considering that only PET bottles should be collected. In each dimensional flow of PET bottles, the proportion of transparent bottles prevailed; it ranged from 31% to 70%. Based on the results of the experiment, almost all PET bottle categories had a standard shape, except packaging for food products and household chemicals, in which 26-27% of PET bottles had a non-standard shape. The results about charactersitic of source-separated PET bottles are fundamental for goal-oriented design and implementation of collection, recycling technologies, secondary separation facilities, the economics of recycling intitatives and reverse vending machines for collecting materials.

Mechanical Optimization of Concrete with Recycled PET Fibres Based on a Statistical-Experimental Study

Discarded polyethylene terephthalate (PET) bottles have damaged our ecosystem. Problems of marine fauna conservation and land fertility have been related to the disposal of these materials. Recycled fibre is an opportunity to reduce the levels of waste in the world and increase the mechanical performance of the concrete. PET as concrete reinforcement has demonstrated ductility and post-cracking strength. However, its performance could be optimized. This study considers a statistical-experimental analysis to evaluate recycled PET fibre reinforced concrete with various fibre dose and aspect ratio. 120 samples were experimented under workability, compressive, flexural, and splitting tensile tests. The results pointed out that the fibre dose has more influence on the responses than its fibre aspect ratio, with statistical relation on the tensional toughness, equivalent flexural strength ratio, volumetric weight, and the number of fibres. Moreover, the fibre aspect ratio has a statistical impact on the tensional toughness. In general, the data indicates that the optimal recycled PET fibre reinforced concrete generates a superior performance than control samples, with an improvement similar to those reinforced with virgin fibres.

Contamination Levels in Recollected PET Bottles from Non-Food Applications and their Impact on the Safety of Recycled PET for Food Contact

PET beverage bottles have been recycled and safely reprocessed into new food contact packaging applications for over two decades. During recollection of post-consumer PET beverage bottles, PET containers from non-food products are inevitably co-collected and thereby enter the PET recycling feed stream. To explore the impact of this mixing on the safety-in-use of recycled PET (rPET) bottles, we determined the concentrations of post-consumer substances in PET containers used for a range of non-food product applications taken from the market. Based on the chemical nature and amounts of these post-consumer substances, we evaluated their potential carry-over into beverages filled in rPET bottles starting from different fractions of non-food PET in the recollection systems and taking worst-case cleaning efficiencies of super-clean recycling processes into account. On the basis of the Threshold of Toxicological Concern (TTC) concept and Cramer classification tools, we present a risk assessment for potential exposure of the consumer to the identified contaminants as well as unidentified, potentially genotoxic substances in beverages. As a result, a fraction of 5% non-food PET in the recycling feed stream, which is very likely to occur in the usual recollection systems, does not pose any risk to the consumer. Our data show that fractions of up to 20%, which may sporadically be contained in certain, local recollection systems, would also not raise a safety concern.

Phthalate Esters and Their Potential Risk in PET Bottled Water Stored under Common Conditions

A great deal of attention has been paid lately to release of phthalate esters (PAEs) from polyethylene terephthalate (PET) bottles into PET bottled drinking water due to their potential endocrine-disrupting effects. Three kinds of PAEs, including diethyl phthalate (DEP), dimethyl phthalate (DMP) and dibutyl phthalate (DBP), were detected in 10 popular brands of PET bottles in Beijing, ranging from 101.97 μg/kg to 709.87 μg/kg. Meanwhile, six kinds of PAEs, including DEP, DMP, DBP, n-butyl benzyl phthalate (BBP), di-n-octyl phthalate (DOP) and di(2-ethylhexyl) phthalate (DEHP), were detected in PET bottled water, ranging from 0.19 μg/L to 0.98 μg/L, under an outdoor storage condition, while their concentrations ranged from 0.18 μg/L to 0.71 μg/L under an indoor storage condition. Furthermore, the concentrations of PAEs in brand D and E bottles were slightly increased when the storage time was prolonged. In addition, the concentrations of PAEs in commercial water contained in brand B and H bottles and pure water contained in brand E and G bottles were also slightly increased with the increase of storage temperature. Interestingly, DBP mainly contributed to the increased PAEs levels in simulation water. These results suggest that a part of the PAEs in PET bottled water originated from plastic bottles, which was related to the storage time and temperature. However, the PAEs in PET bottled water only pose a negligible risk to consumers if they follow the recommendations, such as storage at a common place (24 °C), away from sun and in a short period of time.

Comment on "exposure to microplastics (<10 μm) associated to plastic bottles mineral water consumption: The first quantitative study by Zuccarello et al. [Water Research 157 (2019) 365-371]"

Microplastics in food is a relatively new research field with only few studies available so far. Scientists have been pointing out that some of these studies apply questionable analytical methods. Nevertheless, media often use such results to gain attention of the readers. It is therefore of particular significance, that only those scientific studies are published, clearly presenting valid data on the content of microplastics in food. Unfortunately, the study by Zuccarello et al. shows very critical aspects regarding analytical methods used and conclusions made. The applied procedure is not described and, therefore, does not allow any assessment by other groups, which is indispensable prerequisite of any scientific publication. Moreover, the analytical method used for the identification and quantification of microplastic particles - SEM-EDX - is not sound and not validated. Therefore, in our opinion the results on the contamination of bottled mineral water with microplastics published by Zuccarello et al. are more than questionable.

Novel bifunctional dispersing agents from waste PET packaging materials and interaction with cement

Modified polyethylene terephthalate polymers (MPETs), as a novel dispersing agent, were successfully prepared from polyethylene terephthalate (PET (flakes of empty bottles in order to recycle waste from one particularly abundance packaging material. Different techniques were used to characterize the MPETs samples, including attenuated total reflectance Fourier transform infrared (ATR-FTIR), gel permeation chromatography (GPC), differential scanning calorimetry (DSC), scanning electron microscope (SEM), dynamic light scattering (DLS) and Brunauer-Emmett-Teller (BET) surface area. The fluidity and mini-slump retention of fresh cement paste were tested to evaluate the dispersion capability of the MPETs. The effect of MPETs on the setting time and compressive strength of the cement paste were studied. The adsorptive behavior of the MPETs dispersions was examined using total organic carbon (TOC) and zeta potential to interpret the interaction of the MPETs with cement. The results show that the MPETs can be adsorbed on the cement particles and improve the flowability, setting time and the compressive strength of cement paste. Adding value by generating a cheap and effective dispersing agent from recycling waste polymers is a great approach toward eco-friendly waste management.

Microplastic in bottled natural mineral water - literature review and considerations on exposure and risk assessment

Microplastics have been ubiquitously found and identified in aquatic and terrestrial environments for several years. Due to their occurrence in the oceans, microplastics were also found and characterised in seafood products and in other foods and beverages such as beer, honey and table salt. Very recently, microplastic particles were also determined in bottled mineral water. The objective of this publication is to present and discuss a compilation of the currently available literature data on microplastics in bottled mineral water. The related oral exposure of the consumer from substances present in microplastics and from the plastics particles themselves is estimated and toxicological arguments for and considerations on risk assessment from the consumption of bottled mineral water containing microplastics are presented. Exposure estimations based on the reported microplastic amounts found in mineral water and the assumption of total mass transfer of small molecules like additives and oligomers present in the plastic would not raise a safety concern. Available toxicokinetic data suggests that marginal fraction of the ingested low amount of microplastics can be absorbed, if at all, the conclusion is very likely that the reported amounts present in bottled mineral water do not raise a safety concern for the consumer. Considering the use of plastic materials in our daily life, occurrence of microplastics in beverages is likely a minor exposure pathway for plastic particles. Due to recent progress in analytical methods and the public discussion on plastics marine litter, public concern about eating and drinking microplastics with food, and related safety issues was raised. However, a better data basis for exposure estimates and risk assessment would be very helpful to better accommodate consumer concerns. The intention of this paper is to deliver a contribution to this topic taking the bottled mineral water as a case example.

Water consumption management in polyethylene terephthalate (PET) bottles washing process via wastewater pretreatment and reuse

The increasing recycling of polyethylene terephthalate (PET) bottles requires more and more fresh water during washing the bottles. The post-washing wastewater is often treated as effluent, whereas it could be reused in the technological process after appropriate pretreatment. In this paper, coagulation together with flocculation is proposed for use in the pretreatment of the wastewater arising during PET bottles washing. Five flocculants and six coagulants were tested. The turbidity and total organic carbon (TOC) were reduced by up to 98% and 69%, respectively. Out of the tested flocculants, Praestol 611 BC at a dose of 2 mg/dm³ had the best performances. The best coagulant in TOC reduction was PIX-123. As for turbidity reduction, ALS was the best, but PIX-123 was comparable, and therefore, PIX-123 was indicated as most suitable in simultaneous reduction of TOC and turbidity. The coagulation and flocculation together reduced the amount of pollutants and contaminants in the post-washing wastewater to the levels allowing the water to be reused in the washing process, which could bring both economical and ecological benefits.

Is there an environmentally optimal separate collection rate?

Material recycling often leads to environmental benefits when compared to thermal treatments or landfilling and is therefore positioned in the waste hierarchy as the third priority after waste prevention and reuse. To assess the environmental impacts of recycling and the related substitution of primary material, linear steady-state models of physical flows are typically used. In reality, the environmental burdens of collection and recycling are likely to be a non-linear function of the collection rate. This short communication aims at raising awareness of the non-linear effects in separate collection systems and presents the first non-linear quantitative model for PET bottle recycling. The influence of collection rates on the material quality and the transport network is analyzed based on the data collected from industrial partners. The results highlight that in the present Swiss recycling system a very high collection rate close to 100% yields optimum environmental benefits with respect to global warming. The empirical data, however, provided indications for a decrease in the marginal environmental benefit of recycling. This can be seen as an indication that tipping points may exist for other recycling systems, in which the environmental benefits from substituting primary materials are less pronounced than they are for PET.

Effects of storage temperature and time of antimony release from PET bottles into drinking water in China

Antimony (Sb) concentrations were measured in 10 brands of PET bottled drinking water available in supermarkets in China. To simulate general storage habits based on market research, these PET bottles with drinking water were stored for 4 weeks in a lab or a car trunk during the summer. Although the PET package material of brand A had the lowest Sb level (142.71 ± 29.81 μg/g), it showed a significant increase in Sb concentrations when stored in both the car trunk and the lab. There was significant release of Sb from the PET bottles into the water following 24 h of incubation at ≥ 40 °C (40, 50, 60, and 70 °C), especially at 70 °C. The potential health risk of Sb release from PET bottles was calculated based on daily intake values and determined to be acceptable for consumers under normal storage conditions.