Determination of plastic additives in packaging by liquid chromatography coupled to high resolution mass spectrometry

Development of a generic approach for monitoring leachable compounds in hospital pharmacy-prepared prefilled plastic packaging by ultrahigh-performance liquid chromatography coupled to high-resolution mass spectrometry with postcolumn infusion

Prefilled plastic packaging is time- and cost-effective in hospital pharmacy because it prevents waste, preparation errors, dosage errors, microbial contamination and accidents. This packaging mostly includes prefilled syringes (PFS), intravenous (IV) bags and vials intended for long-term storage that can be used for immediate treatment. There is a rising availability in the market for prefilled drug products due to their practical approach. Leachable compounds could be evaluated in hospital pharmacy-prepared prefilled drug solutions. The Pharmacy Department at the Lausanne University Hospital has developed an innovative, highly sensitive, and generic method by postcolumn infusion based on ultrahigh-performance liquid chromatography coupled to high-resolution mass spectrometry (LC-HRMS) for the analysis of plastic additives in hospital pharmacies. The postcolumn infusion solution was developed with 2% ammonium hydroxide in methanol on a representative set of 30 candidate compounds with different physical-chemical properties, such as log P and molecular structure, to represent the most important categories of additives. The LODs obtained for all compounds ranged from 0.03 to 7.91 ng/mL with linearity up to 250 ng/mL. Through this screening method, plastic additives can be rapidly identified due to the combined use of retention time, exact mass (including isotopic pattern) and MS/MS spectra. In addition, the users can screen for vast categories of plastic additives, including plasticizers, epoxy monomers, antioxidants, UV stabilizers, and others. The screening is facilitated by assessments of a complex in-house-built database for extractable and leachable trace assessment (DELTA), containing 205 compounds for unambiguous identification. Relative response factors were established for all analytes to obtain a semiquantitation of compounds. Moreover, the database also contains valuable estimative toxicology information, which was obtained through calculating their permissible dose exposure threshold; thus, estimative toxicology assessment can be performed for identified compounds in prefilled drug products. This method and the database were applied to a hospital pharmacy-prepared prefilled vancomycin syringe for paediatric use. Ultrasound-assisted dispersive liquid-liquid microextraction (UA-DLLME) was used to prepare the samples for leachable analysis. As a result, 17 plastic additives were formally identified, and their concentrations were estimated. A toxicology assessment was performed by comparing their concentrations with their theoretical PDE thresholds. In conclusion, the prefilled drug solution released a negligible amount of known leachables that appeared to be safe for use in neonates and children.

A novel measurement strategy and a dedicated sampling cell for the parallel characterization of organic and inorganic constituents in polymer samples by concurrent laser ablation ICP-OES and EI-MS

Polymeric composite materials are gaining importance due to their universal applicability and easy adaptability for their intended use. For the comprehensive characterization of these materials, the concurrent determination of the organic and the elemental constituents is necessary, which cannot be provided by classical analysis methods. In this work, we present a novel approach for advanced polymer analysis. The proposed approach is based on firing a focused laser beam onto a solid sample placed in an ablation cell. The generated gaseous and particular ablation products are measured online parallelly by EI-MS and ICP-OES. This bimodal approach allows direct characterization of the main organic and inorganic constituents of solid polymer samples. The LA-EI-MS data showed excellent agreement with the literature EI-MS data allowing not only the identification of pure polymers but also of copolymers, as demonstrated with acrylonitrile butadiene styrene (ABS) as the sample. The concurrent collection of ICP-OES elemental data is vital for classification, provenance determination, or authentication studies. The applicability of the proposed procedure has been demonstrated by analysis of various polymer samples from everyday use.

Solving a microplastic dilemma? Evaluating additive release with a dynamic leaching method for microplastic assessment (DyLeMMA)

Microplastics and plastic additives are contaminants of emerging environmental concern. Static leaching methods are commonly applied to assess the rate and extent of additive release from microplastics. However, this approach may not be representative of environmental conditions where near infinite dilution or percolation commonly occur. We evaluated three different approaches for assessing additive leaching under environmentally relevant sink conditions, culminating in the refinement and validation of DyLeMMA (Dynamic Leaching Method for Microplastic Assessment). Analysis was performed using a high-resolution liquid chromatography-mass spectrometry method enabling targeted quantification of additives and screening for non-intentionally added substances. Using four different plastics, sink conditions were maintained over the duration of the test, thereby avoiding solubility limited release and ensuring environmental relevance. Background contamination from ubiquitous additive chemicals was minimised, thereby providing good sensitivity and specificity. Resulting data, in the form of additive release curves, should prove suitable for fitting to release models and derivation of parameters describing additive leaching from microplastics.Key attributes of DyLeMMA:•Environmentally relevant dynamic leaching method for microplastics, demonstrated to maintain sink conditions over the test duration,•Simple, fast, and cost-effective approach without complication of using a solid phase sink,•Provide data suitable for understanding microplastic leaching kinetics and mechanisms.

Migration study of chemical additives from low density polyethylene (LDPE) into dahi

Dahi is widely used fermented milk product in India. Low Density Polyethylene (LDPE) is the most extensively used packaging material for Dahi in India. The present study was conducted to develop the analytical methods for extraction and migration of chemical additives from LDPE into dahi. Characterization of dahi packaging materials collected from five different firms was done by Fourier Transform Infrared Spectroscopy. Focused ultrasound solid liquid extraction method was observed to be better as compared to solid liquid extraction method as the former extracted maximum additives from the LDPE. Out of total 76 chemical additives extracted from LDPE, only eight (10.52%) matched with the existing positive list of polyolefins prescribed by Bureau of Indian Standads (BIS). The overall migration of chemical additives from all the LDPE samples was below their maximum limit as given by BIS standards. Chemical additives which migrated into the simulants included the antioxidants, fatty acids and their derivatives, unreacted hydrocarbons, plasticizers, lubricants and surfactant etc.

Leaching and extraction of additives from plastic pollution to inform environmental risk: A multidisciplinary review of analytical approaches

Plastic pollution is prevalent worldwide and has been highlighted as an issue of global concern due to its harmful impacts on wildlife. The extent and mechanism by which plastic pollution effects organisms is poorly understood, especially for microplastics. One proposed mechanism by which plastics may exert a harmful effect is through the leaching of additives. To determine the risk to wildlife, the chemical identity and exposure to additives must be established. However, there are few reports with disparate experimental approaches. In contrast, a breadth of knowledge on additive release from plastics is held within the food, pharmaceutical and medical, construction, and waste management industries. This includes standardised methods to perform migration, extraction, and leaching studies. This review provides an overview of the approaches and methods used to characterise additives and their leaching behaviour from plastic pollution. The limitations of these methods are highlighted and compared with industry standardised approaches. Furthermore, an overview of the analytical strategies for the identification and quantification of additives is presented. This work provides a basis for refining current leaching approaches and analytical methods with a view towards understanding the risk of plastic pollution.

Organophosphite Antioxidants in Mulch Films Are Important Sources of Organophosphate Pollutants in Farmlands

Organophosphite antioxidants (OPAs) are important auxiliary antioxidants used in plastic polymers and can be oxidized to organophosphate esters (OPEs) during production and processing. In this work, the occurrence of OPAs and OPEs in farmlands with or without mulch film applications was investigated. Six OPAs and five OPEs were detected, with the median concentrations of 2.66 ng/g (∑₆OPAs) and 100 ng/g (∑₅OPEs) in the film-mulching soil and 1.16 ng/g (∑₆OPAs) and 47.9 ng/g (∑₅OPEs) in the nonfilm-mulching soil, respectively. The oxidative derivative of AO168 (tris (2,4-di-tert-butylphenyl) phosphite), a typical OPA, AO168═O (tris (2,4-di-tert-butylphenyl) phosphate) was frequently detected in farmlands at the concentrations of 0-731 ng/g, which is much higher than that of the commercial OPEs (0-12.1 ng/g). This suggests that the oxidation derivatives of OPAs (OPAs═O) might be important OPE contaminants in soils. Mulch films could be their important source. According to the simulation migration experiment, the emission risk ranges of AO168 and AO168═O from mulch films to soils in China were estimated to be 3.96-87.6 and 10.5-95.3 tons/year, respectively, which were much higher than those of OPEs from sewage sludge applications. Simulation experiments also demonstrated that oxidation was the major pathway for OPAs in soils. OPAs with small substituent groups could be potential sources for organophosphate diesters. For the first time, the serious pollution of OPAs and OPAs═O in soils has been reported, and mulch films have been identified as their potential source.

Extraction of stabilizers from polymers: Separation of oligomeric hindered amine light stabilizers and phenolic antioxidants from polyolefins using liquid chromatography and high-temperature solid-phase extraction

The extraction of different stabilizers from a polymer matrix and the subsequent separation of said stabilizers is one of the most important as well as challenging undertakings in polymer chemistry. A multitude of stabilizers exists, each of which may be hard to extract, be difficult if not impossible to separate from other stabilizers or necessitate very selected and time-consuming intermediate stages for separation. Certain polymer matrices even pose additional challenges, such as polyolefins being only soluble at elevated temperatures. One of the most well-established approaches for the extraction of stabilizers is Soxhlet extraction. However, even this highly successful approach shows only limited success with regard to the extraction of the ever more relevant oligomeric stabilizers or the extraction of multiple stabilizers in a one-shot approach. Moreover, performing Soxhlet extractions often necessitates ≥24 h. For these reasons, alternative approaches for the extraction of stabilizers from polymers are highly sought after. An approach with enormous potential is solid-phase extraction, which allows the selective retention and enrichment of stabilizers. Herein, the very first application of high-temperature solid-phase extraction for the extraction of stabilizers from polyolefin matrices is described; as with other extraction techniques, the identification and quantification of the stabilizers is then allowed. At temperatures of 140-160°C, it was possible to adsorb common polyolefin stabilizers selectively on a silica solid phase from their polyolefin matrix. To predict high-temperature solid-phase extraction test conditions, first LC tests are necessary, offering an elegant approach for the separation of polyolefins from oligomeric stabilizers, which was not achievable until now.

Plastic Bottle Cap Recycling—Characterization of Recyclate Composition and Opportunities for Design for Circularity

In line with efforts to create a circular economy of plastics, recent EU legislation is strengthening plastic bottle recycling by ambitious separate collection targets and mandatory recycled content obligations. Furthermore, explicit design requirements on the caps of bottles and composite beverage packaging have been introduced. These caps are typically made of polyethylene or polypropylene and often contain additives such as slip agents and anti-statics. Commercially available bottle cap recyclates (BCRs) as well as specifically formulated model compounds were analyzed in terms of composition by means of infrared spectroscopy, differential scanning calorimetry, and high-performance liquid chromatography. Their composition was found to be heterogeneous due to polyolefin cross-contamination, directly reflecting the diversity of cap materials present in the market. Slip agent legacy additives originating from the initial use phase were found and quantified in both commercial and model cap recyclates. This highlights the opportunity for redesigning plastic bottle caps not only in response to regulatory requirements, but to pursue a more comprehensive strategy of product design for circularity. By including considerations of polymer resin and additive choice in cap manufacturing, more homogeneous waste streams could be derived from plastic bottle cap recycling, enabling recycling into more demanding and valuable applications.

Identification of additives in polymers from single-use bioprocessing bags by accelerated solvent extraction and ultra-high performance liquid chromatography coupled with high-resolution mass spectrometry

Single-use technologies are increasingly used in biopharmaceutical manufacturing. Despite their advantages, these plastic assemblies draw concern because they are a potential source of contamination due to extractable and leachable compounds (E&Ls). Characterising E&Ls from such materials is a necessary step in establishing their suitability for use. Therefore, there is an urgent need for sensitive methods to identify and quantitatively assess compounds in plastic materials. Accelerated solvent extraction (ASE) is a powerful technique that can be reliably used for this purpose. In this study, ASE followed by liquid chromatography and Orbitrap-based High Resolution Accurate Mass (HRAM) mass analysis was found to be an efficient and versatile method for the determination of additives in different multilayer polymer systems from single-use bags. ASE optimisation was performed using a design of experiments approach. The type of solvent, temperature, swelling agent addition, static time and number of cycles were the selected variables. Optimum conditions were dependent on the type of plastic film. Ethyl acetate and cyclohexane were selected individually as optimum solvents. Optimum temperatures were 90-100 °C. Pressure was set at 1500 psi and extraction time was 30 min in 2 cycles. Swelling agent addition was necessary with polar extraction solvents. More than 100 additives and degradation products were confidently identified by HRAM MS. Correlations between the type and levels of identified additives and the type of polymer system were established. In addition, degradation behaviour and pathways for some additives can be addressed.

Determination of the Contents of Antioxidants and Their Degradation Products in Sodium Chloride Injection for Blood Transfusion

The infusion bag is mainly made up of polyolefin polymer. Antioxidants are usually added to these polymer materials in the production process to prevent the materials from aging and enhance the stability of the materials. Because of the potential harm of antioxidants to human body, it is necessary to limit the amount of antioxidants migrating to the pharmaceutical solutions. In the present study, we developed and validated the HPLC method for the simultaneous quantification of antioxidants and their degradation products migrating to sodium chloride solution for injection. A total of six antioxidants and six their degradation products were separated and simultaneously determined by using a Waters Symmetry RP18 column (250 × 4.6 mm, 5 μm) and gradient elution of methanol/acetonitrile/acetic acid-water (1 : 99, v/v) at a flow rate of 1.0 mL/min. The detective wavelength was set at 277 nm, and the column temperature was maintained at 35°C. The method was validated in terms of limit of detection (LOD, 0.011-0.151 μg/mL), limit of quantification (LOQ, 0.031-0.393 μg/mL), intraday precision (0.25%-3.17%), interday precision (0.47%-3.48%), linearity (0.1-46.8 μg/mL, r > 0.9994), stability (0.35%-3.29%), and accuracy (80.39%-104.31%). In the extraction experiment, antioxidants, BHT, 1010, 1330, 1076, and 168, and their degradation products, 1310 and DBP, were detected in the packaging materials. Only 1310 was detected in the migration experiment. The maximum daily dosage of sodium chloride for blood transfusion is three bags, and the content of 1310 in long-term testing samples is from 0 to 12 months ranging from 37.44 μg/3 bags to 48.71 μg/3 bags. The daily intake of 1310 did not exceed 48.71 μg, which was much lower than its permitted daily exposure (PDE, 300 μg/day). Therefore, the antioxidants and their degradation products migrating into the drug solution would not cause drug safety risks.

Emissions of selected monoaromatic hydrocarbons as a factor affecting the removal of single-use polymer barbecue and kitchen utensils from everyday use

The main focus of this study is the emission of monoaromatic hydrocarbons because these are the preliminary factors of potential solvent and monomer residues present in single-use plastic barbecue and kitchen utensils comprising polystyrene, polypropylene, natural cellulose, and biodegradable polymers intended for use with hot meal or beverages. Herein, the emissions of monoaromatic hydrocarbons (styrene, benzene, toluene, ethylbenzene, and xylene compounds and the total volatile organic compounds (TVOC)) from nine types of disposable plastic utensils are reported. Seventy two samples of single-use plastic utensils were conditioned at 40 and 80 °C using a stationary emission microchamber system. The average TVOC released from the studied polystyrene, polypropylene, and natural or biodegradable utensils were (2.3 ± 1.3), (1.01 ± 0.15), and (0.48 ± 0.37) μg g^-1, respectively, at 40 °C and (11.1 ± 1.2), (46.1 ± 9.5), and (5.5 ± 1.1) μg g^-1, respectively, at 80 °C. Significant emissions of styrene (ranged from 3.5 up to 15.3 × 10³ ng∙g^-1), toluene (from 2.8 up to 0.53 × 10³ ng∙g^-1), and ethylbenzene (from 3.7 up to 5.7 × 10³ ng∙g^-1) from the studied samples were observed, especially at 80 °C. Thus, elevated temperatures increase the potential emission of solvent and monomer residues from plastics and could affect the quality of consumed meals or beverages, such as taste. Additionally, to determine the possible interactions between the measured chemical compounds in the plastic utensils, the Pearson's correlation coefficients were calculated.

Identification of Additives in Polypropylene and Their Degradation under Solar Exposure Studied by Gas Chromatography-Mass Spectrometry

Additives are absolutely essential in the development of commercial polymeric materials. Accordingly, an exhaustive control of composition and evolution in these additives over time is necessary to validate their performance and safety during their shelf life and, consequently, their ultimate applications. Gas chromatography coupled with mass spectrometry, GC-MS, is described in the present work to identify and analyze the content of a wide variety of additives, commonly used in industrial polymeric materials. First, the identification under the present experimental protocol of additives with a relatively high molecular weight (Irganox 1330 and Irganox 1010) has been successfully attained. Second, the evolution under solar exposure over time has been analyzed by GC-MS for 11 additives and derived substances, which have been identified in a commercial polypropylene sample, estimating the corresponding depletion times. In addition, the resultant increase of carbonyl groups in the polymeric macrochains along the photo-oxidation has been also determined by infrared spectroscopy. Therefore, GC-MS is found to be a reliable tool for the analysis of the evolution of commonly used polymer additives under specific degradation conditions, which can be very useful in the formulation of improved future additivations.

Exposure to melamine and its derivatives in childcare facilities

Melamine (MEL) and its derivatives are widely used in many consumer products, including furniture, kitchenware, and plastics. However, very limited knowledge exists on human exposure to MEL and its derivatives, especially in the indoor environment. Here, we determined the occurrence and distribution of 11 MEL derivatives in childcare facilities and estimated children's exposure through dust ingestion and dermal absorption. We analyzed dust and samples of nap mats, a commonly used item in many childcares, from eight facilities located in the United States. Eight MEL-based compounds were detected in dust, and total MEL concentrations ranged from 429 to 117,000 ng/g. The most abundant compounds found in the dust samples were MEL, cyanuric acid (CYA), ammeline (AMN), and ammelide (AMD), with median concentrations of 1620, 585, 1060, and 299 ng/g, respectively. MEL, CYA, AMN and 2,4,6-tris[bis(methoxymethyl)amino]-1,3,5-triazine (TBMMAT) were also detected in nap mats with median concentrations of 45.6, 19.8, 1510 and 2.5 ng/g, respectively. ΣMEL concentrations in mat covers (median 709 ng/g) were significantly higher than those in mat foam (median 15.1 ng/g). Estimated daily intakes (EDIs) of MEL and its derivatives via dust ingestion were two orders of magnitude higher than the EDIs through dermal absorption, but both were below the established tolerable daily intake levels. This is the first report on exposure to MEL and its derivatives in the childcare environment.

The role of mass spectrometry and related techniques in the analysis of extractable and leachable chemicals

In addition to degradation products, impurities, and exogenous contaminants, industries such as pharmaceutical, food, and others must concern themselves with leachables. These chemicals can derive from containers and closures or migrate from labels or secondary containers and packaging to make their way into products. Identification and quantification of extractables (potential leachables) and leachables, typically trace level analytes, is a regulatory expectation intended to ensure consumer safety and product fidelity. Mass spectrometry and related techniques have played a significant role in the analysis of extractables and leachables (E&L). This review provides an overview of how mass spectrometry is used for E&L studies, primarily in the context of the pharmaceutical industry. This review includes work flows, examples of how identification and quantification is done, and the importance of orthogonal data from several different detectors. E&L analyses are driven by the need for consumer safety. These studies are expected to expand in existing areas (e.g., food, textiles, toys, etc.) and into new, currently unregulated product areas. Thus, this topic is of interest to audiences beyond just the pharmaceutical and health care industries. Finally, the potential of universal detector approaches used in other areas is suggested as an opportunity to drive E&L research progress in this arguably understudied, under-published realm.

Occurrence of plastic additives in outdoor air particulate matters from two industrial parks of Tarragona, Spain: Human inhalation intake risk assessment

Plastic additives include several kinds of chemicals that are added to the polymer matrix to improve the final product quality and prevent deterioration effects. They are used in a large quantity of materials, so their presence in the environment is expected. This study has developed and validated a method based on gas chromatography-mass spectrometry after pressurised liquid extraction to determine sixteen plastic additives including UV-stabilizers, aromatic and phenolic antioxidants and some of their degradation products in particulate matter (PM₁₀) from outdoor air. Apparent recoveries were above 85% for most of compounds and low detection limits (pg m^-3) were achieved. This is the first study to determine these types of contaminant in the PM₁₀ of outdoor air from two locations surrounded by different industries. Various compounds were found in almost all samples; BHT, BHT-Q, 2,4-DTBP, BHT-CHO, UV320, UV328, Irgafos168 and Iragonx1076, with concentrations ranging from < MQL to 2860 pg m^-3. Estimated daily intakes (EDIs) via ambient inhalation were calculated for each polymer additive and for different subpopulation groups classified by age. Two possible exposure scenarios (low, based on geometric mean, and high, 95th percentile) were simulated, and 0.51 ng kg_bw^-1 day^-1 was the EDI in the worst case scenario for children.

Determination of the mass transport properties of chemical additives in polypropylene material/simulated food system

The mass transport process (migration) of five additives from three different types of polypropylene (PP) films into selected food simulants was studied. The migration tests were carried out at different time-temperature conditions, and the concentration of additives in polymer matrix and food simulants were analysed by high-performance liquid chromatography (HPLC). With all data, the mass transport properties for migration kinetics (partition and diffusion coefficients) were determined. Results showed that the partition coefficient was affected significantly by the temperature and simulants' properties, whereas little affected by the types of PP film and molecular weight of substance. The polarity, structure and shape of substances can also have an influence in their partition between the polymer matrix and food simulants. Additionally, comparison results between the experimental diffusion coefficients and the calculated values by Piringer model suggested that the current migration model with the default modelling parameters for PP does not describe realistically the diffusion coefficients of additives. The calculated diffusion coefficients were greater than the experimental values, as a consequence, the migration of chemical additives will be overestimated. For more realistic migration calculations, more accurate modelling parameters in Piringer model should be established and the effect of food on migration should be high interest in future work.

Direct screening of food packaging materials for post-polymerization residues, degradation products and additives by liquid extraction surface analysis nanoelectrospray mass spectrometry (LESA-nESI-MS)

Materials in direct contact with food should be monitored for the presence of species able to migrate into food. A direct method based on liquid extraction surface analysis nanoelectrospray mass spectrometry (LESA-nanoESI-MS) was developed for the analysis of the migrating species from a polymer film. Different types of molecules: post-polymerization residues, degradation products (oligomers resulting from polymer recycling, products of polymer oxidative degradation) and anti-oxidant additives (vitamin E) were demonstrated to be detected and identified, and determined quantitatively if relevant calibration standards are available. The method was validated by a comparison a standard method based on with bulk extraction mass spectrometry. It offers considerable advantages over the latter in terms of drastically reduced analysis time and solvent consumption. Also, LESA-nanoESI-MS produced simpler spectra (limited to compounds able to migrate into food) than Direct Analysis in Real Time (DART).

Investigation of Drug-Packaging Interactions with Mass Spectroscopy Detectors: A Meta-Synthesis of the Literature

Background

The production of hospital-compounded medicines with a longer shelf life raises questions about drug-packaging interactions, especially desorption events involving extractables and leachables (E/L). A meta-synthesis of the literature was performed to describe which mass spectrometer is suitable for identifying and quantifying E/L.

Methods

A meta-synthesis of studies focused on the identification or quantification of E/L published between January 1997 and December 2017 was performed. Inclusion criteria were E/L studies dealing with pharmaceutical products, in which mass spectrometry (MS) coupled to liquid chromatography (LC) or gas chromatography (GC) was used. The full-text articles had to be available and written in English. Articles about food packaging, environmental contamination, counterfeit compounds, pharmacokinetics, or process-related impurity studies were excluded. Two researchers independently assessed the papers according to a score based on a seven-item questionnaire.

Results

In total, 32 papers matched our criteria and were included in the meta-synthesis. For qualitative analysis with LC, quadrupole time-of-flight (QTOF; n=4) and ion trap (n=4) mass detectors were used the most; and with GC, single quadrupole (n=8). For quantification studies with LC, QTOF (n=3) and triple quadrupole (n=2) were used the most; and with GC, single quadrupole (n=7).

Conclusions

For simultaneous qualitative and quantitative analysis of E/L with LC, QTOF or Orbitrap is a suitable detector. For quantitative analysis with LC only, triple quadrupole is suitable. For qualitative and quantitative analysis with GC, single quadrupole can be used.

Evaluation of Mechanical Properties and Volatile Organic Extractable to Investigate LLDPE and LDPE Polymers on Final Packaging for Semisolid Formulation

Plastic material is used for a wide variety of commercial packaging due to being inexpensive, lightweight, and due to its resistance. In pharmaceutics, container-content compatibility studies are required for product authorization. Many guidelines and publications are available; however, the information is often only related to the raw materials used to produce packaging. During the manufacturing process, substances can be added to improve the product characteristics and performance, resulting in a processed material that is considerably different from the unprocessed material. In this study, the mechanical properties of low-density polyethylene (LDPE) and linear low-density polyethylene (LLDPE) specimens fabricated according to standard ISO 527 and specimens fabricated with the same materials, but obtained from final packaging, were evaluated. Furthermore, we examined the interaction between a semisolid formulation and LLDPE and LDPE as a final packaging, by subjecting two samples to accelerated degradation testing. Then, mechanical properties and volatile organic extractable were evaluated. Simulated solar radiation did not induce changes in the packaging mechanical properties and no extracts were detectable. The thermal shock strongly influenced the mechanical behavior, and interactions between packaging contents were identified. The present work underlines the difference between analyzing the standard ISO specimens versus samples obtained from final packaging in order to evaluate the packaging under real use conditions. An evaluation on the final packaging, instead on standard specimens, can provide information about the plastic material after the manufacturing process and the interaction between packaging and content.

Evaluation of solvent systems for optimized extractables studies of single use bioprocessing solutions

Despite their advantages, there is concern that single-use systems used in biopharmaceutical manufacture might release potentially toxic substances during standard unit operations that negatively impact cell growth. Characterization of the extractables profile for single-use systems is necessary to know which compounds potentially become leachables under operational cell culture conditions. A key issue in the design of extractables studies is the composition of the model solvent, in particular its pH and polarity. In this study, a new approach, based on design of experiments (DoE), has been applied to determine the composition of the model solvent for extractable profiling of single-use bags (SUBs). Particular focus was placed on the determination of the degradation products of the antioxidant Irgafos 168^®, due to evidence that some of these degradation products have cytotoxic effects on CHO cells. Results indicated that 2-propanol:water is the most appropriate solvent for the extraction of highly hydrophobic compounds with polar groups and/or acid-base properties from SUBs. The described DoE approach simplifies the number of experiments, evaluates all possible solvent water mixtures to select the best extraction solvent based on polarity, establishes the influence of each variable and provides information about variable interaction, which represents an important improvement over current best practice. The developed approach was applied to seven SUBs from different vendors and production dates facilitating the identification of potentially non-satisfactory films for cultivation of CHO cell lines under process conditions.

Rapid determination of oligomeric hindered amine light stabilizers in polymeric materials

Hindered amine light stabilizers are essential for the stabilization of synthetic polymers, particularly for materials used for outdoor applications. Although up to now a considerable number of studies dealing with the analytics of this class of stabilizers had been published, especially the determination of oligomeric hindered amine light stabilizers is still an analytical challenge. In the current work, a fast and simple liquid chromatographic method for the quantitative determination of oligomeric hindered amine light stabilizers is presented. A key aspect of this method is their completely different retention behavior depending on the pH, enabling a single peak elution approach by a pH gradient run. This allows a quantitation with simple UV detection independent of the actual oligomeric composition. Calibration curves within the concentration range relevant for the analysis of real polymer samples (LOQ = 70 mg/L) were constructed with R² values above 0.99. Spiked extracts from polyolefin samples showed recovery rates between 97.3 and 102.9% for five different commercial hindered amine light stabilizers. Relative standard deviations were between 2.0 and 3.9%. Furthermore, it was demonstrated that the employed approach can be easily adapted for mass spectrometry detection.

Geotextile composition, application and ecotoxicology-A review

Geosynthetics is the umbrella term for thin, flexible material sheets applied in civil and environmental engineering, of which geotextiles form the largest group. Most geotextiles consist of a polymer from the polyolefin, polyester or polyamide family, and additives to improve their stability. The polymer may degrade into microplastic particles over time and under various conditions and can cause adverse effects, as species may ingest these particles or encounter adverse effects due to the interference of the particles with e.g. their photosynthesis system in the case of algae. Leaching of additives may occur from the intact material, as they are often not covalently bound to the polymer backbone, but is greatly enhanced when micro-sized plastic particles have been formed. A total of 42 polymer additives were identified, of which 26 had ecotoxicity information available in terms of a REACH persistence, toxicity and bioaccumulation (PBT) assessment. Of these, 15 were classified as (very) persistent and 2 as toxic. A survey to assess potential toxicity of the remaining 16 substances revealed that no ecotoxicity studies had been performed on 13 of these compounds. For 3 compounds, other toxicity data was found, as well as of several chemical groups known to be used as additives in geotextiles. The current knowledge is thus lacking in two domains: on the one hand, ecotoxicity data is scarce as many substances have not yet been the subject of ecotoxicological studies. On the other hand, in situ toxic effects might be missed by the current approach of single compound toxicity testing. Moreover, environmental occurrence data of the additives are extremely scarce.

Multiresidual LC-MS analysis of plasticizers used in PVC gaskets of lids and assessment of their migration into food sauces

Plasticizers may migrate from polyvinyl chloride (PVC) gaskets into the foodstuffs mainly by direct contact during the packaging and sterilization procedure, but also by means of occasional contacts occurring during shipment and storage. The present work reports a reliable liquid chromatography-mass spectrometry (LC-MS) method able to quantify the main plasticizers used in the PVC closure gaskets for metal lids to verify their compliance in both food contact materials and foodstuffs. The atmospheric pressure chemical ionization in the positive ion mode resulted the best performing interface for the multiresidual detection of the plasticizers taken into account, followed by selected/multiple reaction monitoring, selected ion monitoring or full scan experiments, depending on the compounds to detect. The method was single-laboratory validated, demonstrating to reach a good sensitivity, thus making possible to perform analysis without any preliminary sample purification or concentration step. It proved to be effectively applicable not only for the determination of plasticizers in PVC gaskets but also in complex food matrices. In particular, it was applied for monitoring plasticizer migration into sauces placed in contact with the lids in worst storage conditions, observing therefore their trend during the shelf-life. Copyright © 2016 John Wiley & Sons, Ltd.

Detection and Identification of Leachables in Vaccine from Plastic Packaging Materials Using UPLC-QTOF MS with Self-Built Polymer Additives Library

The direct contact of plastic parts with the medical products raises the possibility that plastic-related contaminants (leachables) may be present in the finished medical product. The leachable components from plastic materials may impact the safety and efficacy of the final medical product, so identification and determination of the leachables are essential for the safety assessment of medical products. A method to identify main leachables-polymer additives in medical products was developed by ultraperformance liquid chromatography-quadrupole time-of-flight-mass spectrometry (UPLC-QTOF MS) and a self-built library. The library contains 174 additives and the information on their names, formulas, structures, retention times, fragments, classifications, origin, and corresponding MS(E) and MSMS spectra. The reliability of the construction process of the library was guaranteed by the system stability and suitability test. Identification parameters of library application, such as mass error, retention times, fragments, and isotope pattern, were evaluated. Leachables in real vaccine and the intermediates were identified using automatic library searching. In vaccine, the peak m/z 239.0887 that could not be assigned by the library was identified as dimethyl 2-hydroxy-1,3-cyclohexanedicarboxylate using a series of elucidation tools. As a result, the concentrations of leachables in vaccine and the intermediates ranged from 0.85 to 21.91 μg/L.

Advances in the determination of hindered amine light stabilizers - A review

Within this paper we discuss analytical strategies for the characterization and quantitation of hindered amine light stabilizers (HALS) an important sub-group of polymer additives. For the determination of monomeric HALS a range of mature and reliable techniques exists, allowing their determination in polymer extracts. If qualitative or semi-quantitative information suffices, certain techniques are capable of sampling directly from the polymer surface with limited or no sample preparation. Different strategies for the determination of complex oligomeric HALS in extracts from polymer samples are discussed. Here, approaches providing only a sum parameter including all HALS oligomers have been distinguished from more sophisticated technologies allowing the determination of single oligomers, their degradation and by-products. Particularly, the latter issue is facing increased interest as it provides important information for polymers aging studies. A tabulated overview provides comprehensive information on different analytical techniques suitable for HALS determination.

Study of the partition coefficients Kp/f of seven model migrants from LDPE polymer in contact with food simulants

This study evaluated the influence of parameters such as temperature and type of low-density polyethylene (LDPE) film on the log Kp/f values of seven model migrants in food simulants. Two different types of LDPE films contaminated by extrusion and immersion were placed in contact with three food simulants including 20% ethanol, 50% ethanol and olive oil under several time-temperature conditions. Results suggest that most log Kp/f values are little affected by these parameters in this study. In addition, the relation between log Kp/f and log Po/w was established for each food simulant and regression lines, as well as correlation coefficients, were calculated. Correlations were compared with data from real foodstuffs. Data presented in this study could be valuable in assigning certain foods to particular food simulants as well as predicting the mass transfer of potential migrants into different types of food or food simulants, avoiding tedious and expensive laboratory analysis. The results could be especially useful for regulatory agencies as well as for the food industry.