An evaluation of the migration of antimony from polyethylene terephthalate (PET) plastic used for bottled drinking water

Advancing Analytical Techniques in PET and rPET: Development of an ICP-MS Method for the Analysis of Trace Metals and Rare Earth Elements

Despite the extensive use of recycled polyethylene terephthalate (rPET) in food contact materials (FCMs), research on the presence of heavy metals (HMs) and rare earth elements (REEs) during various recycling stages (e.g., flakes, granules, and preforms) remains limited. This study aimed to address these gaps by validating a rapid and sensitive analytical method to quantify 26 HMs and 4 REEs in PET and rPET matrices. An ICP-MS method was validated per EURACHEM guidelines, assessing linearity, limits of detection (LOD), limits of quantification (LOQ), accuracy, and repeatability. The method was employed for initial screening of HMs and REEs classified as non-intentionally added substances (NIASs) in PET and rPET samples. The findings showed high accuracy and reliability, with recovery rates between 80% and 120%. Analysis revealed varying concentrations of HMs and REEs, with the highest levels in 100% rPET preforms, notably Zn, Cu, and Al among HMs, and La among REEs. The study identified critical contamination points during the recycling process, highlighting the need for targeted interventions. This research provides a crucial analytical framework for assessing HMs and REEs in PET and rPET, ensuring FCM safety compliance and supporting efforts to enhance rPET product safety, promoting public health protection and advancing the circular economy.

On-site monitoring of dissolved Sb species in natural waters by an automatic system using flow injection coupled with hydride generation atomic fluorescence spectrometer

Antimony (Sb) is a toxic and potentially carcinogenic element in the environment. The toxicity of Sb(III) is ten times that of Sb(V). Therefore, on-site monitoring technique for dissolved Sb species is crucial for the study of Sb environmental processes. In this study, an automated, portable, and cost-effective system was developed for field simultaneous analysis of Sb(III) and Sb(III + V) in natural waters. The system comprised a portable atomic fluorescence spectrometer equipped with a built-in electrochemical H2 generator to reduce the consumption of acid/borohydride solution and make the atomizer more stable for on-site analysis. Flow injection technique was also used to achieve on-line pretreatment of water samples, including filtration, acidification, pre-reduction, and hydride generation procedures. Under the optimal conditions, the limits of detection (3σ, n = 11) of the developed method were 0.015 μg/L and the linear ranges were 0.05-5.0 μg/L for both Sb(III) and Sb(III + V). The relative standard deviations (n = 11) of the spiked samples of Sb(V) were 3.2% (0.05 μg/L), 3.3% (0.2 μg/L), and 1.7% (0.5 μg/L), respectively. The spiked recoveries of lake water, treated wastewater, and seawater ranged from 97.0% to 108.5%. The novel system of flow injection coupled with hydride generation atomic fluorescence spectrometer (FI-HG-AFS) was applied to carry out an 18-h fixed-point monitoring at a secondary settling tank of a wastewater treatment facility in Xiamen University, and a 6-h real-time underway analysis in the surface seawater of Dongshan Bay, China, proving that the system was capable of long-term monitoring in the field.

Impact of a nanofiltration system on microplastic contamination in Geneva groundwater (Switzerland)

Microplastics (MPs) have been observed in the oceans, fresh waters, karstic water and remote water bodies. However, little is known on groundwater contamination, which is a natural resource of utmost importance for millions of people and is often perceived as a reliable source of water. Moreover, nanofiltration is perceived as a reliable technology to remove contaminants from water. In this study, large sample volumes of a silty-sandy gravel aquifer and the corresponding nanofiltered water were analysed for the presence of MPs (> 20 µm) using Fourier transform infrared (FTIR) microscopy. Concentration in ground water was 8 ± 7 MPs/m3 and increased to 36 ± 11 MPs/m3 in nanofiltered water. All MPs had a maximum Ferret diameter lower than 500 µm. Size distribution of MPs was towards the small size class (20-50 µm). In groundwater, 33% of MPs were detected in the smallest size class (20-50 µm) and 67% in the 50-100-µm-size class. In comparison, around 52% of MPs in nanofiltered water were observed in the 20-50 µm size class. Moreover, 33% of the MPs observed in nanofiltered water were in the 50-100 µm size class and 15% in the 100-500-µm-size class. From a chemical point of view, different plastic polymers were identified in groundwater and in nanofiltered water, such as polypropylene (PP), polyvinyl chloride (PVC), ethylene (vinyl acetate) copolymer (EVA), polyethylene (PE), polyethylene terephthalate (PET), polymethyl methacrylate (PMMA) and other polymer materials (such as polystyrene-based copolymers, vinyl-based copolymers). Fibres were observed in all samples, but only a small number of fibres (near 1%) were identified as PP synthetic fibres in nanofiltered water. Furthermore, no clear difference of fibre concentrations was observed between groundwater (232 ± 127 fibres/m3) and nanofiltered water (247 ± 118 fibres/m3). Groundwater had extremely low levels of microplastics, and although the nanofiltration effectively removes suspended particulate matter, it slightly contaminates the filtered water with MPs.

Potential Migration and Health Risks of Heavy Metals and Metalloids in Take-Out Food Containers in South Korea

The consumption of take-out food has increased worldwide; consequently, people are increasingly being exposed to chemicals from food containers. However, research on the migration of metals from containers to food is limited, and therefore, information required to determine the health risks is lacking. Herein, the amount of transfer of nine metals and metalloids (Pb, Sb, Cd, Ge, Co, Mn, Sn, As, and Hg) from food containers to food in South Korea was assessed from take-out food containers classified into paper and plastic container groups. The sample containers were eluted over time by either warming with 4% acetic acid at 70 °C or cooling with 4% acetic acid at 100 °C /deionized water at 25 °C. It was analyzed using an inductively coupled plasma mass spectrometer and a direct mercury analyzer. The reliability of the quantitative results was verified by calculating the linearity, limit of detection, and limit of quantification. We found that the amount of metals and metalloids (Pb, Sb, Cd, and Co) eluting over time was highly significant in the plastic group. Regardless of the food simulant and elution time, the amount of Sb transferred from the food containers to food was substantially higher in the plastic (average concentration: 0.488-1.194 μg/L) than in the paper group (average concentration: 0.001-0.03 μg/L). Fortunately, all food containers were distributed at levels safe for human health (hazard index: 0.000-64.756%). However, caution is needed when warm food is added to food containers. Overall, our results provide baseline data for the management and use of take-out containers.

A Drosophila model of gestational antimony exposure uncovers growth and developmental disorders caused by disrupting oxidative stress homeostasis

The toxic heavy metal antimony (Sb) is ubiquitous in our daily lives. Various models have shown that Sb induces neuronal and reproductive toxicity. However, little is known about the developmental toxicity of Sb exposure during gestation and the underlying mechanisms. To study its effects on growth and development, Drosophila stages from eggs to pupae were exposed to different Sb concentrations (0, 0.3, 0.6 and 1.2 mg/mL Sb); RNA sequencing was used to identify the underlying mechanism. The model revealed that prenatal Sb exposure significantly reduced larval body size and weight, the pupation and eclosion rates, and the number of flies at all stages. With 1.2 mg/mL Sb exposure in 3rd instar larvae, 484 genes were upregulated and 694 downregulated compared to controls. Biological analysis showed that the disrupted transcripts were related to the oxidative stress pathway, as verified by reactive oxygen species (ROS) scavenger N-acetylcysteine (NAC) and glutathione (GSH) intervention experiments. Sb exposure induced oxidative stress imbalance could be rectified by chelation and antioxidant effects of NAC/GSH. The Drosophila Schneider 2 (S2) model further demonstrated that NAC and GSH greatly ameliorated cell death induced by Sb exposure. In conclusion, gestational Sb exposure disrupted oxidative stress homeostasis, thereby impairing growth and development.

Antimony in Polyethylene Terephthalate-Bottled Beverages: The Migration Puzzle

A novel strategy to assess the main variables that potentially affect the migration of antimony from PET bottles to beverages, including mineral waters and juices, is herein proposed. In a preliminary step, an LC-ICP-MS method previously used for water analysis was optimized to correct identify Sb species present in the studied matrices using HRMS. Subsequently, the influence of temperature and storage time up to 30 days on Sb migration from PET bottles into peach and pineapple juices of the same brand was studied. Storing PET bottled drinks at elevated temperatures (i.e., in a hot car or in summer) can cause antimony migration to exceed the limits allowed in the EU or USA. Because the behavior observed differed from the results reported for Sb migration in mineral waters, a second approach was proposed: three mineral water and two juice samples were kept in different PET containers and stored at an elevated temperature (up to 60 °C) to understand the role of the PET type and matrix simultaneously. This study demonstrated that both matrix characteristics and type of PET bottle greatly influence antimony leaching, highlighting the need to consider these variables together when conducting migration experiments. The obtained results can be helpful for developing future legislation concerning migration of pollutants from packing to food commodities.

Ecotoxicity of PM10 emissions generated during controlled burning of waste PET

Domestic waste is often burned either as fuel for winter heating or in open areas, simply to get rid of waste. Polyethylene terephthalate (PET) represents an important component of plastics usage as well as of plastic waste produced. While most studies attempt to characterize environmental risk of open burning of mixed household waste, present work evaluates chemical and ecotoxicological parameters of particulate matter (PM) produced during controlled burning of PET samples. In the PM₁₀ samples, polycyclic aromatic hydrocarbon and heavy metal concentrations were measured, ecotoxicity was evaluated using the kinetic Vibrio fischeri bioassay. Both chemical composition and ecotoxicity of the 4 samples showed significant correlation, regardless of the colored or colorless nature of the original PET sample. Antimony was found in considerable concentrations, in the range of 6.93-16.9 mg/kg. PAHs profiles of the samples were very similar, showing the dominance of 4-and 5-ring PAHs, including carcinogenic benzo(a)pyrene.

Application of hydride generation - microwave plasma - atomic emission spectrometry and partial least squares regression for the determination of antimony directly in water and in PET after alkaline methanolysis

Antimony is present in different types of plastics as a catalyzer residue and/or as a synergistic fire retardant; relatively high concentrations of this element reported in polyethylene terephthalate (PET) bottles and wrappers as well as its migration to the edible products or to different environment compartments are of concern. In this work, Sb determination is such products had been undertaken using hydride generation - microwave plasma - atomic emission spectrometry. To avoid harsh conditions typically reported for the digestion of PET, alkaline methanolysis was introduced whereas water samples were analyzed directly. Another original approach was to perform quantification by partial least squares regression (PLS1), taking spectral data from 2-nm range that comprised two emission lines (217.581 nm and less intense 217.919 nm). For PET, the calibration solutions contained Sb-free digest and covered the Sb concentration range 80-230 μg L^-1. For the analysis of water, the calibration range was 0.5-10 μg L^-1 and aqueous standard solutions were used. PLS1 provided reliable prediction, eliminating spectral interferences detected in the presence of PET digests and compensating for the spectral changes observed at low Sb concentrations. After standard addition to the real-world samples, the percentage recoveries were in the range 93.8-99.3% and 68-102% for PET and for bottled water, respectively. The method quantification limit for PET was 10 mg kg^-1 and for water it corresponded to 0.20 μg L^-1. The concentrations of Sb found in the analyzed samples were: 154-279 mg kg^-1 for PET bottles and <0.5-5.30 μg L^-1 for water.

Physiological, biochemical, and hormonal changes in rats exposed to bottled water left in a hot car and the freezer

The aim of this study was to investigate the effects of bottled water left in the car and those left in the refrigerator on the physiological and biochemical parameters of male rats. Eighteen male albino rats were randomly divided into control, warmed bottled water (WBW), and cooled bottled water (CBW) groups. The concentrations of bisphenol A (BPA) and antimony (Sb) in the water samples were measured. Results showed that the levels of BPA and Sb were higher in bottled water left in the car and those kept at room temperature (control), relative to the bottled water samples kept in the fridge. Bodyweight, some metabolic indicators, cTnT and CRP levels, hematological parameters, testosterone level, and sperm quality were significantly affected by storage conditions. These results indicate that storage conditions can potentially affect the quality of bottled water, which in turn can affect the biological parameters of living organisms. Moreover, since the concentrations of BPA and Sb were least in bottled water kept in the refrigerator, we recommend that manufacturers and households should endeavor to keep bottled water under cold storage.

Unpacking the complexity of the PET drink bottles value chain: A chemicals perspective

Chemicals can migrate from polyethylene terephthalate (PET) drink bottles to their content and recycling processes may concentrate or introduce new chemicals to the PET value chain. Therefore, even though recycling PET bottles is key in reducing plastic pollution, it may raise concerns about safety and quality. This study provides a systematic evidence map of the food contact chemicals (FCCs) that migrate from PET drink bottles aiming to identify challenges in closing the plastic packaging loop. The migration potential of 193 FCCs has been investigated across the PET drink bottles lifecycle, of which 150 have been detected to migrate from PET bottles into food simulants/food samples. The study reveals that much research has focused on the migration of antimony (Sb), acetaldehyde and some well-known endocrine-disrupting chemicals (EDCs). It indicates and discusses the key influential factors on FCCs migration, such as physical characteristics and geographical origin of PET bottles, storage conditions, and reprocessing efficiency . Although, safety and quality implications arising from the recycling of PET bottles remain underexplored, the higher migration of Sb and Bishphenol A has been reported in recycled (rPET) compared to virgin PET. This is attributed to multiple contamination sources and the variability in the collection, sorting, and decontamination efficiency. Better collaboration among stakeholders across the entire PET bottles lifecycle is needed to ensure sustainable resource management and food contact safety of rPET.

Assessment of Potentially Toxic Elements and Associated Health Risk in Bottled Drinking Water for Babies

Potentially toxic elements are chemical pollutants which are dangerous to human health, especially for babies and children. Because their presence has been detected in baby food and baby drinking water, exposure to these elements is mainly due to ingestion. For this reason, the main objective of this study was quantification of 12 potentially toxic elements, including Ba, Co, Cu, Zn, Mn, Ni, Li, Fe, Pb, Cd, Cr, Sb, by ICP–MS, from 19 samples of bottled baby water. Based on the levels obtained, a health risk assessment was performed of the risk caused by their consumption, as well as an analysis of the quality of the samples. Excep iron, the values obtained for all other metals were below the limits imposed by the legislation in force. The risk analysis shows that Hazard index values were included in Risk Class 1, with a very low hazard level. The order of Cancer Risk values is as follows, Cd < Cr < Ni < Pb. As a general conclusion, we can say that the samples can be intended for consumption by children and infants.

Magnetic Ion Imprinted Polymers (MIIPs) for Selective Extraction and Preconcentration of Sb(III) from Environmental Matrices

Antimony(III) is a rare element whose chemical and toxicological properties bear a resemblance to those of arsenic. As a result, the presence of Sb(III) in water might have adverse effects on human health and aquatic life. However, Sb(III) exists at very ultra-trace levels which may be difficult for direct quantification. Therefore, there is a need to develop efficient and reliable selective extraction and preconcentration of Sb(III) in water systems. Herein, a selective extraction and preconcentration of trace Sb(III) from environmental samples was achieved using ultrasound assisted magnetic solid-phase extraction (UA-MSPE) based on magnetic Sb(III) ion imprinted polymer-Fe3O4@SiO2@CNFs nanocomposite as an adsorbent. The amount of antimony in samples was determined using inductively coupled plasma optical emission spectrometry (ICP-OES). The UA-MSPE conditions were investigated using fractional factorial design and response surface methodology based on central composite design. The Sb(III)-IIP sorbent displayed excellent selectivity towards Sb(III) as compared to NIIP adsorbent. Under optimised conditions, the enrichment factor, limit of detection (LOD) and limit of quantification (LOQ) of UA-MSPE/ICP-OES for Sb(III) were 71.3, 0.13 µg L-1 and 0.44 µg L-1, respectively. The intra-day and inter-day precision expressed as relative standard deviations (%RSDs, n = 10 and n = 5) were 2.4 and 4.7, respectively. The proposed analytical method was applied in the determination of trace Sb(III) in environmental samples. Furthermore, the accuracy of the method was evaluated using spiked recovery experiments and the percentage recoveries ranged from 95-98.3%.

Characteristics of Potentially Toxic Elements, Risk Assessments, and Isotopic Compositions (Cu-Zn-Pb) in the PM10 Fraction of Road Dust in Busan, South Korea

The pollution status of ten potentially toxic elements (PTEs), isotopic compositions (Cu, Zn, Pb), and the potential ecological risk posed by them were investigated in the PM10 fraction of road dust in Busan Metropolitan city, South Korea. Enrichment factors revealed extremely to strongly polluted levels of Sb, Cd, Zn, Pb, and Cu in the PM10 fraction of road dust, with Sb levels being the highest. Statistical analyses showed that the major cause for contamination with PTEs was non-exhaust traffic emissions such as tire and brake wear. Cu and Zn isotopic compositions of road dust were related to traffic-related emission sources such as brake and tires. Pb isotopic compositions were close to that of road paint, indicating that Pb was a different source from Cu and Zn in this study. No significant health risk was posed by the PTEs. Taking into account the total length of road in Busan, a high quantity of PTEs in road dust (PM10) can have serious deleterious effects on the atmospheric environment and ecosystems. The results of metal concentrations and isotopic compositions in road dust will help identify and manage atmospheric fine particle and coastal metal contamination derived from fine road dust.

Antimony, a pollutant of emerging concern: A review on industrial sources and remediation technologies

Technologies for remediation of industrial effluents and natural sources contaminated with antimony - a pollutant of emerging concern - are just emerging. The complex speciation of antimony makes it challenging to devise effective remediation technologies. Antimony is used in several industrial applications and comes into the environment majorly through human induced activities such as antimony mining and other activities involving the use of various products containing antimony. Many researchers are working on the important task of developing methodologies to stop or limit the release of antimony into the environment through these activities. Antimony removal is an important requirement in nuclear industry as well due to the formation of its radioactive isotopes during power plant operations. Thus, better antimony remediation or removal techniques can have wider applications ranging from domestic water treatment and industrial effluent remediation to safe isolation of radioactive waste in the nuclear industry. Proper understanding of the problem is very important in designing the source appropriate remediation technique. Treatment methodologies needed for antimony effluents from antimony mining and smelting industries are different from antimony decontamination in nuclear reactors. The problem of antimony leaching from a polyethylene terephthalate bottle is very much different from the leaching of antimony from mining wastes. Each process necessitates custom-made treatment methodologies by taking into account various factors including the speciation and concentration. The current review is focused on this aspect. The review attempts to bring out a clear understanding on various industry specific sources of antimony pollution and the available antimony removal/remediation technologies.

Dynamic flow and pollution of antimony from polyethylene terephthalate (PET) fibers in China

Antimony (Sb), a regulated contaminant, is added as a catalyst in the process of polyethylene terephthalate (PET) synthesis. Previously, Sb release from PET bottles and films was studied. However, Sb release from PET fibers (the most common form of PET) is limited. Therefore, a network model of material flow for PET fibers in China is developed, and the anthropogenic Sb flow and release entering into the hydrosphere, pedosphere, and atmosphere are studied based on microexperiments and macromodels. To compensate for the uncertainty caused by material flow analysis, Sb pollution in the surrounding areas (the drinking water of nearby residents and sediments of nearby river area) is further explored by combining field investigations and sample analysis. The results are as follows: 1) the manufacture stage of PET fibers is the main source of Sb release (2926 t), followed by the dyeing (2223 t) and weaving (908 t) stages; 2) Sb release (1108 t) from waste PET fibers subjected to landfill disposal is the highest. Sb release (872 t) from discarded fiber waste is second highest. Sb release from PET fibers subjected to mechanical recycling, incineration, and chemical recycling is 784, 284, and 25 t, respectively; and 3) an obvious source-sink relationship is found between anthropogenic Sb in the rivers and sediments and the intensity of the industries. This study suggests that Sb from PET fibers should be properly managed to prevent widespread dispersion in the hydrosphere, pedosphere, and atmosphere.

Improving the Efficiency for the Production of Bis-(2-Hydroxyethyl) Terephtalate (BHET) from the Glycolysis Reaction of Poly(Ethylene Terephtalate) (PET) in a Pressure Reactor

The depolymerization process of PET by glycolysis into BHET monomer is optimized in terms of reaction temperature and time, by carrying out the process under pressure to be faster for reducing the energy required. Almost pure BHET has been obtained by working in a pressure reactor at 3 bar both at 220 and 180 °C after short reaction times, while for longer ones a mixture of oligomers and dimers is obtained. Depending on the potential application required, the obtention of different reaction products is controlled by adjusting reaction temperature and time. The use of a pressure reactor allows work at lower temperatures and shorter reaction times, obtaining almost pure BHET. To the best of our knowledge, except for microwave-assisted procedures, it is the first time in which pure BHET is obtained after such short reaction times, at lower temperatures than those usually employed.

Dynamic flows of polyethylene terephthalate (PET) plastic in China

Polyethylene terephthalate (PET) is a widely used plastic material that may cause significant environmental pollution. China is a major global producer and consumer of PET. Previous studies have focused on the effects of toxic elements from PET (e.g., antimony leached from PET products) on the environment. However, detailed information about PET, particularly about the PET production, trade, use, and recycling in China, is limited. This study developed a network model of PET flows in China, including the production, market trade, manufacturing and use, and waste management and recycling stages. Based on this network model, the characteristics of PET flows during three periods of development for the PET industry were analyzed. The results show that the fiber and bottle manufacturing industries are the industries with the largest PET in-use stocks. The PET flows showed different characteristics in the terms of waste import, recycling, and disposal (mechanical recycling, chemical recycling, incineration, landfill, and discarding) in the different periods of PET industrial development. Notably, the amount of discarded PET was significant, and the treatment of waste PET would probably be a challenge in the future. Policies for improving the PET cycling system were provided on the basis of the study results to promote the management and sustainable utilization of PET materials.

Antimony and PET bottles: Checking facts

Over the last 30 years, bottled water has gained in popularity reaching high sales world-wide. Most of this water is sold in polyethylene terephthalate (PET) bottles. About 15 years ago, the presence of antimony in water in those PET bottles raised concerns and studies on the subject have been regularly published since then. This review aims to evaluate whether the use of good analytical practices and the correct design of these studies support the accepted facts (i.e., PET is the origin of antimony presence in bottled waters, antimony concentrations are usually below regulated values, temperature increasing favours antimony leaching). The detailed analysis of published data has confirmed these facts but has also revealed frequency of faulty analytical practices and a lack of well-designed studies. A better understanding of the structure of PET polymer in the bottles, coupled with statistically-robust antimony release experiments, is required to progress in the field.

Human health risk assessment of some bottled waters from Romania

The paper presents the quality status of 14 brands of bottled water, with sources of groundwaters from different mountain areas alongside the Carpathian Mountains from Romania. A number of 12 physico-chemical parameters (ammonium, bicarbonate, electrical conductivity, carbonate, chemical oxygen demand, chloride, nitrate, nitrite, pH, sulphate, total hardness, turbidity), 9 metals and metalloids (Li, B, Na, Mg, Al, K, Ca, Sr, Ba) and 17 heavy metals (V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, As, Mo, Ag, Cd, In, Tl, Pb, Bi) were determined and studied. The quality status, the potential contamination and the health risk assessment of bottled waters were assessed, by using the drinking water quality index, the heavy metal pollution index, the heavy metal evaluation index, the degree of contamination and the human health risk indices. Hierarchical cluster analysis was applied, indicating similarities among the studied bottled waters based on their metal content. The Piper diagram reveals that the majority of bottled water samples fall into the Ca, Mg, Na, K, Cl^-, SO₄^2-, CO₃^2-, HCO₃^- categories. The quality of bottled waters based on the indices results indicated marginal, poor and very-poor quality status of the studied water samples, while the health risk assessment indices presented potential risks at aluminium, chloride and nitrate for the inhabitants who used those water samples with the purpose of drinking. The pollution indices with respect to metals generally reflected a low pollution status. This study represents the first attempt in assessing the overall quality of some bottled water collected from the mountain area, Romania, likewise assessing the comprehensive human health risk due to several chemical elements determined in water in amounts around and exceeding the maximum allowable concentrations. This research can be useful for development of potential strategies for risk control and management in the field of drinking water.

Mobilisation of antimony from microplastics added to coastal sediment

Antimony (Sb) widely occurs in plastics as a pigment and reaction residue and through the use and recycling of electronic material enriched in Sb as a flame retardant synergist. In this study, clean estuarine sediment has been contaminated by different microplastics prepared from pre-characterised samples of different types of plastic (including a rubber) containing a range of Sb concentrations (256-47,600 μg g^-1). Sediment-plastic mixtures in a mass ratio of 100:1 were subject to 6-h extractions in seawater and in seawater solutions of a protein (bovine serum albumin; BSA) and a surfactant (taurocholic acid; TA) that mimic the digestive conditions of coastal deposit-feeding invertebrates. Most time-courses for Sb mobilisation could be defined by a second-order diffusion equation, with rate constants ranging from 44.6 to 0.0216 (μg g^-1)^-1 min^-1. Bioaccessibilities, defined as maximum extractable concentrations throughout each time course relative to total Sb content, ranged from <0.01% for a polycarbonate impregnated with Sb as a synergist exposed to all solutions, to >1% for acrylonitrile butadiene styrene containing a Sb-based colour pigment exposed to solutions of BSA and TA and recycled industrial polyethylene exposed to BSA solution. The potential for Sb to bioaccumulate or elicit a toxic effect is unknown but it is predicted that communities of deposit-feeders could mobilise significant quantities of Sb in sediment contaminated by microplastics through bioturbation and digestion.

Blowing Kinetics, Pressure Resistance, Thermal Stability, and Relaxation of the Amorphous Phase of the PET Container in the SBM Process with Hot and Cold Mold. Part I: Research Methodology and Results

The technology of filling drinks without preservatives (such as fresh juices, iced tea drinks, vitaminized drinks) is carried out using hot filling. Mainly due to the production costs and lower carbon footprint, polyethylene terephthalate bottles, commonly called PET, are increasingly used in this technology. In this paper, the main aim is to describe the statistical analysis methodology of the influence of the temperature of the blow mold in the SBM process and the method of hot filling on the macroscopic and microscopic bottle properties. The macroscopic bottle properties were defined by the thickness profile, pressure resistance, thermal stability, and the coefficients of blowing kinetics. Moreover, the influence of the SBM (stretch blow moulding) process on the microscopic PET material properties (in the bottle) relative to the microscopic preform properties was analyzed. The microscopic properties were defined by the degree of crystallite, density, and relaxation of the amorphous phase of the PET material. For this purpose, response surface experiments were performed for the two analyzed factors (independent variables), i.e., the temperature of the blow mold and the method of hot filling. The sample size was investigated to determine the minimum number of repetitions (number of bottles in the measurement series) required to achieve acceptable measurement uncertainty. The research conducted shows that despite fulfilling the postulate of acceptable measurement uncertainty, in terms of the power of ANOVA (analysis of variance) in DOE (design of experiment) the accepted number of bottles in the measurement series is too small. The tests of the bottle material density, material crystallite, and relaxation of amorphous phase relative to the preform material density, material crystallite, and relaxation of amorphous phase show that the microcavity effects occur during the deformation of the PET material, and that these are associated with the orientation of the microstructure. The blow kinetics study shows that there is a gradient of flow of the bottle material over the thickness of the bottle wall during blowing, and it has been deduced that the air temperature between the blow mold and the wall of the blown bottle has an impact on the kinetics of blowing the bottle.

Lead exposure in an Italian population: Food content, dietary intake and risk assessment

BACKGROUND AND AIM

Lead is a highly toxic heavy metal released into the environment after natural and anthropogenic activities. Excluding populations in occupations where there is possible lead contamination, food is the major source of human exposure. In this study, we determined lead contamination in food and beverages consumed in a Northern Italy community and performed a health risk assessment.

METHODS

We collected a total of 908 food samples and measured lead levels using inductively coupled plasma mass spectrometry. Using a validated food frequency questionnaire, we assessed the dietary habits and estimated daily lead dietary intakes in a sample of 719 adult individuals. We performed risk assessment using a benchmark dose and margin of exposure approach, based on exposure levels for both adverse effect of systolic blood pressure and chronic kidney disease.

RESULTS

Foods with the highest lead levels include non-chocolate confectionery (48.7 µg/kg), leafy (39.0 µg/kg) and other vegetables (42.2 µg/kg), and crustaceans and molluscs (39.0 µg/kg). The estimated mean lead intake was 0.155 µg/kg bw-day in all subjects, with little lower intakes in men (0.151 µg/kg bw-day) compared to women (0.157 µg/kg bw-day). Top food contributors were vegetables, cereals, and beverages, particularly wine. In relation to risk assessment, the estimated dietary intake was lower than levels associated with cardiovascular risk and nephrotoxicity.

CONCLUSIONS

Our study provides an updated assessment of lead food contamination and dietary exposure in a Northern Italian community. The margin of exposure risk assessment approach suggests that risk of detrimental effects due to dietary lead intake is low in the investigated population. Nonetheless, these exposure levels for adverse effects are not reference health standards, and no safety threshold value can be established for lead. As a consequence, other and more subtle adverse effects may still occur in vulnerable and occupationally exposed individuals, particularly in relation to the nervous system.

Occurrence and fate of antimony in plastics

Antimony (Sb) is a technology critical element whose presence is ubiquitous in manufactured products, and in particular in plastics where it is used extensively as a flame retardant synergist for brominated compounds, as a catalyst for polyethylene terephthalate production, and as a pigment for colour. This study reviews the usage, regulations and fate of Sb in plastics by examining primary data on its production, applications, contents in and migration from manufactured objects, and presence in and release from waste, including the disposal and recycling routes for this material (i.e., non-controlled disposal, incineration, landfilling and recycling). Consumption of Sb and the relative apportioning of the metalloid between different uses in plastics change continuously and are largely driven by dynamic economic factors; accordingly, reference to secondary data or sources can be misleading. Since Sb is not recovered from plastics, its fate is entirely linked to the fate of plastics themselves which, as far as disposal and recycling are concerned, might be dictated by the presence of co-associated regulated substances such as brominated flame retardants. Significantly, because of the high leachability of Sb from bottom incineration ashes, the EU considers the metalloid as the most problematic substance regarding the potential reuse of this material.

Effect of Polycondensation Catalyst on Fiber Structure Development in High-Speed Melt Spinning of Poly (Ethylene Terephthalate)

We conducted a preliminary study on fiber structural development in the high-speed melt spinning of environmentally friendly polyethylene terephthalate (Ti-PET) synthesized with 25 ppm of titanium-based catalyst, which was compared with conventional PET (Sb-PET) synthesized with 260 ppm of antimony-based catalyst. Gel permeation chromatography of Ti- and Sb-PET resins of intrinsic viscosity 0.63 confirmed that both resins have similar molecular weights and distributions. However, differential scanning calorimetry revealed that the Ti-PET resin exhibited a lower melt–crystallization peak and isothermal melt-crystallization rate than the Sb-PET resin. High-speed melt spinning of the Ti- and Sb-PET was possible up to a spinning velocity of 6 km/min. Two-dimensional wide-angle X-ray diffraction analyses showed that the molecular orientation of the obtained as-spun Ti- and Sb-PET fibers increased with spinning velocity, and a highly oriented, crystalline structure by orientation-induced crystallization started to appear from 5 km/min. Notably, Ti-PET fibers showed a lower degree of crystalline structural development and lower tensile strength compared with Sb-PET fibers under the high-speed spinning conditions. Our results suggest that the catalyst in PET resins can act as nucleating agents in thermal- and orientation-induced crystallization, and that differences in catalyst content can influence PET fiber structure development under extreme conditions in high-speed melt spinning.

Antimony leaching from PET plastic into bottled water in Algerian market

Twelve different brands of mineral water were collected from the Algerian market and analyzed to determine the initial antimony (Sb) content in both the PET package and mineral water. Experiments were conducted under different time conditions: 1, 10, to 365 days, different temperatures: 6, 25, and 40 °C, and different bottles sizes: 0.33 L and 1.5 L. The Sb in mineral water bottles varies between 0.50 and 1.12 μg/L for 0.33 L bottles, and 0.37 to 0.77 μg/L for 1.5 L ones. All of these values remain below the limit set by the European Union of 5 μg/L in drinking water. The diffusion coefficient of Sb in PET has been experimentally determined at 6, 25, and 40 °C, after the content of Sb in 1.5 L PET bottles had been determined. In the second part of the study, a factorial design 2³ enabled a model the migration of antimony (Sb) in the bottled solutions and highlighted the influencing effects, such as temperature (°C), time (h), and thickness (mm) for two different time domains encompassing the entire validity period of the product. A simple polynomial function based on a single parameter has been determined with a precision indicator R² = 0.98. This model has the advantage of being simple and fast. The Chronic Daily Intake (CDI) of Sb has been calculated, for adults. It does not exceed the Environmental Protection Agency (USEPA) regulated CDI value of 400 ng/kg/day. The CDI values for children increase as the weight of the children decreases. The passage from the maximum child weight to the minimum value in the study increases the CDI of 77%.

Determination of trace elements, heavy metals, and antimony in polyethylene terephthalate-bottled local raw cow milk of Iğdır region in Turkey

The presence of several trace elements, heavy metals, and antimony in polyethylene terephthalate-bottled local raw cow milk samples of Iğdır region in Turkey was investigated. The milk samples were analyzed by inductively coupled plasma mass spectrometry after microwave-assisted digestion. Milk samples were categorized into three groups according to the element level intensity in the sample. While 70% of samples showed 2.5 times the maximum Turkish and European permissible level of lead, the lowest lead-contaminated sample exhibited 1.25 times this level. All the examined samples exceeded the maximum permissible limit administrated for arsenic and 35% of samples exhibited 5 times this limit. Results showed 40% of samples contain an antimony level higher than the Turkish maximum allowable concentration. The high antimony content of raw milk samples may be related to the release of antimony from the PET (polyethylene terephthalate) bottles. This study showed high contamination levels of the most toxic trace elements, i.e., lead and arsenic in milk and possible antimony contamination from PET bottles which may cause many health hazards for the consumers.

Antimony Mining from PET Bottles and E-Waste Plastic Fractions

In this study antimony concentration was analyzed in 30 plastic items (from polyethylene terephthalate (PET) bottles and e-waste) directly by X-ray fluorescence spectroscopy (XRF) spectroscopy. PET samples were digested in a microwave oven with aqua regia. The plastic components deriving from e-waste followed three parallel routes: 1. microwave digestion using different acids (aqua regia, 18 M H2SO4, 12 M HCl and 6 M HCl); 2. conversion into ash (at 600 °C) and then microwave digestion with aqua regia, and 3. extraction with 12 M HCl at room temperature for different durations (2 h and 24 h). Results showed that antimony extraction yields from PET were between 57% and 92%. Antimony extraction from e-waste plastics was more challenging: aqua regia was inefficient for poly (acrylonitrile butadiene styrene) (ABS) samples (extraction yield was about 20% only), while on a mixture of ABS and polycarbonate (PC), aqua regia, H2SO4 and HCl exhibited equivalent performances (~21%). Ashed samples returned yields ranging from 20% to over 50%. Room temperature extraction on e-waste plastics obtained lower extraction efficiencies, yet longer incubation durations lead to higher yields. In conclusion, the main challenge associated with antimony mining from plastic waste could be its heterogeneous composition; therefore, the development of reference analytical procedures is highly needed.

Study on Speciation of As, Cr, and Sb in Bottled Flavored Drinking Water Samples Using Advanced Analytical Techniques IEC/SEC-HPLC/ICP-DRC-MS and ESI-MS/MS

The main aim of the research was to develop a complementary analytical approach consisting of bespoke speciation analysis and non-targeted speciation analysis of As, Sb, and Cr in flavored bottled drinking water samples using HPLC/ICP-DRC-MS and ESI-MS/MS. The scope of two previously developed analytical procedures, (1) multielemental speciation procedure for As^III, As^V, Cr^VI, Sb^III, and Sb^V analysis and (2) arsenic speciation procedure for AsB, As^III, DMA, MMA, and As^V quantification, was extended to the analysis of a new sample type in terms of bespoke speciation analysis. As for the non-targeted speciation, analysis size exclusion chromatography was used with ICP-MS and a complementary technique, ESI-MS/MS, was used for the organic species of As, Sb, and Cr screening. Full validation of procedures 1 and 2 was conducted. Procedure 1 and 2 were characterized with precision values in the range from 2.5% to 5.5% and from 3.6% to 7.2%, respectively. Obtained recoveries ranged from 97% to 106% and from 99% to 106% for procedures 1 and 2, respectively. Expanded uncertainties calculated for procedures 1 and 2 ranged from 6.1% to 9.4% and from 7.4% to 9.9%, respectively. The applicability of the proposed procedures was tested on bottled drinking water samples. Results for the real samples in procedure 1 were in the range from 0.286 ± 0.027 [μg L⁻¹] to 0.414 ± 0.039 [μg L⁻¹] for As^III, from 0.900 ± 0.083 [μg L⁻¹] to 3.26 ± 0.30 [μg L⁻¹] for As^V, and from 0.201 ± 0.012 [μg L⁻¹] to 0.524 ± 0.032 [μg L⁻¹] for Sb^V. Cr^VI and Sb^III were not detected in any sample. As for procedure 2, results were in the range from 0.0541 ± 0.0053 [μg L⁻¹] to 0.554 ± 0.054 [μg L⁻¹] for AsB. Results for As^III and As^V obtained with procedure 2 were in good accordance with results obtained with procedure 1. DMA and MMA were not detected in any sample.

Antimony speciation in the environment: Recent advances in understanding the biogeochemical processes and ecological effects

Antimony (Sb) is a toxic metalloid, and its pollution has become a global environmental problem as a result of its extensive use and corresponding Sb-mining activities. The toxicity and mobility of Sb strongly depend on its chemical speciation. In this review, we summarize the current knowledge on the biogeochemical processes (including emission, distribution, speciation, redox, metabolism and toxicity) that trigger the mobilization and transformation of Sb from pollution sources to the surrounding environment. Natural phenomena such as weathering, biological activity and volcanic activity, together with anthropogenic inputs, are responsible for the emission of Sb into the environment. Sb emitted in the environment can adsorb and undergo redox reactions on organic or inorganic environmental media, thus changing its existing form and exerting toxic effects on the ecosystem. This review is based on a careful and systematic collection of the latest papers during 2010-2017 and our research results, and it illustrates the fate and ecological effects of Sb in the environment.

Impact of temperature and storage time on the migration of antimony from polyethylene terephthalate (PET) containers into bottled water in Qatar

Prosperity in Qatar and the consequent stresses on water resources resulted in a sustainable increase in the bottled drinking water market. Reports on health concerns and possible migration of chemicals from the plastic material into the water have driven the current investigation. This study aims to address the extent of antimony (Sb) leaching from polyethylene terephthalate (PET) water bottles subject to temperature variations (24-50 °C) due to Qatar's hot climate and improper storage conditions. A representative basket including 66 different imported and locally produced water bottles was considered. The concentrations of Sb in bottled water ranged from 0.168 to 2.263 μg/L at 24 °C and from 0.240 to 6.110 μg/L at 50 °C. Antimony concentrations in PET bottles at 24 °C was significantly lower than those at 50 °C (p = 0.0142), indicating that the temperature was a principal factor affecting the release of Sb from the plastic into the water. Although the detected Sb amounts were below the guidelines endorsed by WHO and Qatar (standard 5 μg/L) at 24 °C, the concentration measured at 50 °C was higher than the recommended WHO values (6.11 μg/L).

Field-portable-XRF reveals the ubiquity of antimony in plastic consumer products

Very little systematic information exists on the occurrence and concentrations of antimony (Sb) in consumer products. In this study, a Niton XL3t field-portable-X-ray fluorescence (FP-XRF) spectrometer was deployed in situ and in the laboratory to provide quantitative information on Sb dissipated in plastic items and fixtures (including rubber, textile and foamed materials) from the domestic, school, vehicular and office settings. The metalloid was detected in 18% of over 800 measurements performed, with concentrations ranging from about 60 to 60,000μgg^-1. The highest concentrations were encountered in white, electronic casings and in association with similar concentrations of Br, consistent with the use of antimony oxides (e.g. Sb₂O₃) as synergistic flame retardants. Concentrations above 1000μgg^-1, and with or without Br, were also encountered in paints, piping and hosing, adhesives, whiteboards, Christmas decorations, Lego blocks, document carriers, garden furniture, upholstered products and interior panels of private motor vehicles. Lower concentrations of Sb were encountered in a wide variety of items but its presence (without Br) in food tray packaging, single-use drinks bottles, straws and small toys were of greatest concern from a human health perspective. While the latter observations are consistent with the use of antimony compounds as catalysts in the production of polyethylene terephthalate, co-association of Sb and Br in many products not requiring flame retardancy suggests that electronic casings are widely recycled. Further research is required into the mobility of Sb when dissipated in new, recycled and aged polymeric materials.

Determination of antimony compounds in waters and juices using ion chromatography-inductively coupled plasma mass spectrometry

A method was developed by coupling ion chromatography (IC) and inductively coupled plasma mass spectrometry (ICP-MS) for the speciation of antimony. In this study, antimony species such as antimonite [Sb(III)], antimonate [Sb(V)] and trimethyl antimony(V) (TMeSb) were separated in less than 8min using anion exchange chromatography with a Hamilton PRP-X100 column as the stationary phase. Mobile phase A was 20mmolL^-1 ethylenediaminetetraacetic acid (EDTA), 2mmolL^-1 potassium hydrogen phthalate (KHP) in 1% v/v methanol (pH 5.5) and 20mmolL^-1 EDTA, 2mmolL^-1 KHP, 40mmolL^-1 (NH₄)₂CO₃ in 1% v/v methanol (pH 9.0) formed mobile phase B. Detection limits and relative standard deviations (RSD) were 0.012-0.032ngmL^-1 and 2.2-2.8% respectively. This method was applied to bottled waters and fruit juices purchased in Kaohsiung, Taiwan. In water samples, Sb(V) was the major species where as in juices organometallic Sb species were also present.