Bromine in plastic consumer products - Evidence for the widespread recycling of electronic waste.

A range of plastic consumer products and components thereof have been analysed by x-ray fluorescence (XRF) spectrometry in a low density mode for Br as a surrogate for brominated flame retardant (BFR) content. Bromine was detected in about 42% of 267 analyses performed on electronic (and electrical) samples and 18% of 789 analyses performed on non-electronic samples, with respective concentrations ranging from 1.8 to 171,000μgg(-1) and 2.6 to 28,500μgg(-1). Amongst the electronic items, the highest concentrations of Br were encountered in relatively small appliances, many of which predated 2005 (e.g. a fan heater, boiler thermostat and smoke detector, and various rechargers, light bulb collars and printed circuit boards), and usually in association with Sb, a component of antimony oxide flame retardant synergists, and Pb, a heavy metal additive and contaminant. Amongst the non-electronic samples, Br concentrations were highest in items of jewellery, a coffee stirrer, a child's puzzle, a picture frame, and various clothes hangers, Christmas decorations and thermos cup lids, and were often associated with the presence of Sb and Pb. These observations, coupled with the presence of Br at concentrations below those required for flame-retardancy in a wider range of electronic and non-electronic items, are consistent with the widespread recycling of electronic plastic waste. That most Br-contaminated items were black suggests the current and recent demand for black plastics in particular is met, at least partially, through this route. Given many Br-contaminated items would evade the attention of the end-user and recycler, their disposal by conventional municipal means affords a course of BFR entry into the environment and, for food-contact items, a means of exposure to humans

An overview of chemical additives present in plastics: Migration, release, fate and environmental impact during their use, disposal and recycling

Over the last 60 years plastics production has increased manifold, owing to their inexpensive, multipurpose, durable and lightweight nature. These characteristics have raised the demand for plastic materials that will continue to grow over the coming years. However, with increased plastic materials production, comes increased plastic material wastage creating a number of challenges, as well as opportunities to the waste management industry. The present overview highlights the waste management and pollution challenges, emphasising on the various chemical substances (known as “additives”) contained in all plastic products for enhancing polymer properties and prolonging their life. Despite how useful these additives are in the functionality of polymer products, their potential to contaminate soil, air, water and food is widely documented in literature and described herein. These additives can potentially migrate and undesirably lead to human exposure via e.g. food contact materials, such as packaging. They can, also, be released from plastics during the various recycling and recovery processes and from the products produced from recyclates. Thus, sound recycling has to be performed in such a way as to ensure that emission of substances of high concern and contamination of recycled products is avoided, ensuring environmental and human health protection, at all times

Thermal desorption – progressive way of analytical chemistry on plastics and rubbers

Desorpcja termiczna jest to technika pobierania próbek, wykorzystująca ciepło w celu zwiększenia lotności analizowanych substancji w taki sposób, że mogą być usuwane ze stałej osnowy (tworzywa sztucznego, drewna, tekstyliów, wyciągów, piany, włosów, żelu, farby itp.). Umożliwia ona analizę prawie wszystkich rodzajów materiałów na poziomie śladowym, bez wstępnej obróbki próbek. W artykule opisano krótko analityczne podejście do badania wielu materiałów z tworzyw sztucznych / gumy za pomocą desorpcji termicznej z chromatografią gazową połączoną ze spektrometrią masową (TD-GC-MS). Opisano dostępne systemy: bezpośrednią desorpcję termiczną, przekierowaną desorpcję termiczną (zimna pułapka), komorę emisyjną TD-GC-MS, analizę gazów wydzielonych (EGA), a także ich potencjalną przydatność, szczególnie dla przemysłu motoryzacyj¬nego, jak wykrywanie dodatków w tworzywach sztucznych i gumie, lotnych związków organicznych(VOC / SVOC), analizę defektów, ciekłe nastrzyki / ekstrakty / płukanki.Thermal desorption is defined as a sampling technology that utilizes heat to increase the volatility of analytes such that they can be removed (separated) from the solid matrix (plastics, wood, textile, extracts, foam, hair, gel, paint, etc.). Thermal desorption allows analysis of almost all sorts of materials including insoluble materials and complex materials at trace levels without any pretreatment of samples. This paper describes briefly the analytical approach of analyzing a broad range of plastic/rubber materials with thermal desorption gas chromatography coupled with mass spectrometry (TD-GC-MS). In the paper were described available systems: direct thermal desorption, refocusing thermal desorption (cold trap), emission chamber-TD-GC-MS, Evolved-Gas-Analysis (EGA), as well as potential applications for automotive industry: additives from plastic material and rubber, volatile organic compounds (VOC/SVOC), defect analysis, liquid injections/extracts/washes

Stabilization/solidification of salt from a waste incinerator

A laboratory procedure was developed and verified for stabilizing salt produced by an industrial waste incinerator. This procedure is based on salt stabilization by means of an asphalt binder. Conductivity values and relevant anion contents in leachates of stabilized waste with an asphalt coating were near zero. The pH value of these leachates equaled the pH value of the water used, so that the stabilized waste salt represented inert material, posing no environmental hazard. An unusually significant reduction in the volume of processed salt occurred during stabilization. After compacting under 10.4 MPa pressure, the volume of test specimens was almost 55% smaller than the initial salt volume. In practice, this would mean more than a doubling of landfill waste capacity. Volume reduction was successfully explained by means of a mathematical model

Migration of hazardous contaminants from WEEE contaminated polymeric toy material by mouthing

This study evaluated the migration of brominated flame retardants (BFRs), phosphate flame retardants (PFRs), bisphenols (BPA, BPF), and phthalate ester-based plasticizers from recycled polymeric toy material, containing waste electrical and electronic equipment (WEEE), in artificial saliva simulating 1 h of mouthing. In total 12 parts of 9 different toys were tested in triplicate after confirming WEEE specific contamination. Up to 11 contaminants were detected in saliva from one toy sample. The highest migration rate up to 128 ng/(cm2 x h) was found for BPA followed by bis(2-ethylhexyl) phthalate (DEHP) and diisobutyl phthalate (DIBP) with migration rates up to 25.5 and 8.27 ng/(cm2 x h), respectively. In addition to DecaBDE, which was detected in 3 saliva samples at migration rates between 0.09 and 0.31 ng/(cm2 x h), the decaBDE replacements 2,4,6-tris(2,4,6-tribromophenoxy)-1,3,5-triazine (TTBP-TAZ), decabromodiphenyl ethane (DBDPE), resorcinol bis(diphenyl phosphate) (RDP), and hexabromocyclododecane (HBCDD) were detected as well with comparable migration rates. 2,4,6-tribromphenol (246-TBP) reached migration rates up to 1.15 ng/(cm2 x h) in correspondence to the presence of TTBP-TAZ. Tetrabromobisphenol A (TBBPA), BPA, 246-TBP, DEHP, DIBP and triphenyl phosphate (TPHP) were predominantly observed in saliva with a detection frequency between 50 and 75%. Daily intake (DI) values were calculated for relevant analytes and compared to tolerable daily intake (TDI) values. The highest DI values of 72.4, 14.3, 5.74, 2.28 and 2.09 ng/(kg BW x day), were obtained for BPA, DEHP, DIBP, TBBPA, and TPHP, respectively. None of them exceed the TDI value or respective reference dose (RfD)

Discerning between natural and synthetic rubber by analytical pyrolysis (Py-GC/MS)

Rubber is an isoprene polymer (polyisoprene) that can be obtained from different sources (natural/vegetative or mineral/fossil). Analytical pyrolysis has been widely used mainly dealing with vulcanised tyre rubbers with forensic purposes [1 and references therein]. In this study, a detailed pyrolysis biomarker approach is used to discern the origin of unvulcanised rubber samples. Pyrolysis-gas chromatography¿mass spectrometry (Py-GC/MS) was performed using a double-shot pyrolyser (Frontier Laboratories, model 2020i) attached to a GC/MS system Agilent 6890N. Samples 1 mg in weight were introduced into a preheated micro-furnace at (400 °C) for 1 min and the evolved gases were injected into the GC/MS for analysis. The gas chromatograph was equipped with a 30 m HP-5ms-UI column. The oven temperature was held at 50 °C for 1 min and then increased to 100 °C at 30 °C min-1, from 100 °C to 300 °C at 10 °C min-1, and stabilized at 300 °C for 10 min using a heating rate of 20 °C min-1 in the scan modus. The carrier gas was helium at a controlled ¿ow of 1 mL min-1. Mass spectra were acquired at a 70 eV ionising energy in an MSD detector (Agilent 5973). Compound assignment was achieved via single-ion monitoring (SIM) for various homologous series, via low-resolution mass spectrometry, and via comparison with published and stored (NIST and Wiley libraries) data. In a previous study, optimum pyrolysis conditions for the analysis of rubber were established at 400 ºC for 1 minute more drastic pyrolysis conditions i.e. 600 ºC resulted in an excessive degradation of the polymer producing abundant low molecular weight degradation products i.e. xylenes/alkylnaphthalenes and a diminished abundance of the expected polymeric moieties. The analytical pyrolysis results performed at 400º C were in line with hose published elsewhere [1, 2]. In general consisted of a major peak of the monoterpene limonene [1-Methyl-4-(prop-1-en-2-yl)cyclohex-1-ene], isoprene [2-Methylbuta-1,3-diene] and oligomers up to the hexamer (Fig. 1). A remarkably similar chemical profile was found in all polyisoprene samples analysed (2 natural and 2 synthetic) that did not allow a straight forward differentiation between natural and synthetic rubbers. It was necessary to search for minor pyrolysis compounds, mainly known plant biomarkers, to discern between rubbers with distinct origin. These biomarkers included phytosterols (Fig. 2), waxes and tocopherols. Using analytical pyrolysis, we were able to detect molecular markers from plant origin only in natural rubber that were absent from the synthetic samples. The technique is a useful tool to evaluate the authenticity of the raw materials and therefore to detect possible frauds in relation with unvulcanised rubbers.Peer Reviewe

Direct detection of brominated flame retardants from plastic e-waste using liquid extraction surface analysis mass spectrometry

RATIONALE The worldwide generation of plastic electronic waste (e-waste) is reaching epic proportions. The presence of toxic brominated flame retardants (BFRs) within these materials limits their ability to be recycled, resulting in large amounts of e-waste reaching landfills. METHODS Liquid extraction surface analysis mass spectrometry (LESA-MS) employing a chip-based nanoelectrospray coupled to a triple quadrupole mass spectrometer represents a novel control technology for directing e-waste streams for recycling. LESA-MS allows direct sampling and analysis of solid material, capable of detecting BFRs including polybrominated diphenyl ethers (PBDEs) and tetrabromobisphenol A (TBBP-A), the two most common flame retardant additives currently in circulation. RESULTS Authentic PBDE congeners and TBBP-A were deposited on glass and characterised by LESA-MS analysis. PBDEs are notoriously difficult to detect via electrospray; however, they were detected with ease by utilising a combination of nanoelectrospray and solvent doped with ammonium acetate. In situ detection of TBBP-A within plastic e-waste was also possible by performing LESA-MS on the surface of granulated material provided by a commercial waste depot. E-waste sample analysis was completely automated, with each sample analysed in less than 1 min. CONCLUSIONS LESA-MS is fast, simple, and robust allowing unambiguous detection of a range of additives through tandem mass spectrometry. LESA-MS does not require dissolution of the solid matrix nor the sample to be present under vacuum and the use of separative techniques prior to analysis is not necessary