Towards development of a rapid and effective non-destructive testing strategy to identify brominated flame retardants in the plastics of consumer products

Integrating Post-Ionization Separation via Differential Mobility Spectrometry into Direct Analysis in Real Time Mass Spectrometry for Toy Safety Screening

Direct analysis in real time (DART) enables direct desorption and ionization of analytes, bypassing the time-consuming chromatographic separation traditionally required for mass spectrometry (MS) analysis. However, DART-MS suffers from matrix interference of complex samples, resulting in compromised detection sensitivity and quantitation accuracy. In this study, DART-MS was combined with differential mobility spectrometry (DMS) to provide an additional dimension of post-ionization ion mobility separation within a millisecond time scale, compensating for the lack of separation in DART-MS analysis. As proof-of-concept, primary aromatic amines (PAAs), a class of potentially hazardous chemicals, were analyzed in various toy products, including bubble solutions, finger paints, and plush toys. In addition to commercial Dip-it glass rod and metal mesh sampling tools, a customized rapid extractive evaporation device was designed for the accelerated extraction and sensitive analysis of solid toy samples. The incorporation of DMS in DART-MS analysis enabled the rapid separation and differentiation of isomeric analytes, leading to improved accuracy and reliability. The developed protocols were optimized and validated, achieving good linearity with correlation coefficients greater than 0.99 and acceptable repeatability with relative standard deviations less than 10%. Moreover, satisfactory sensitivity was realized with limits of detection and quantitation ranges of 0.2-5 and 1-20 μg/kg (μg/L) for the 11 PAA analytes. The established methodology was applied for the analysis of real toy samples (n = 18), which confirmed its appealing potential for toy safety screening and consumer health protection.

Concentrations and legislative aspects of PBDEs in plastic of waste electrical and electronic equipment in Brazil

Brominated flame retardants (BFRs) have been widely used as additives in polymeric products such as electronic and electrical equipment (EEE) to help meet fire safety regulations. However, some BFRs like polybrominated diphenyl ethers (PBDEs), are now listed under the Stockholm Convention on persistent organic pollutants (POPs) and banned in many countries, due to their adverse health impacts, environmental persistence, and capacity for bioaccumulation and long-range atmospheric transport. Despite this, in Brazil, only a few studies exist of the presence of these contaminants in the environment, and even fewer in waste EEE (WEEE). Against this backdrop, this study measured the presence of PBDEs in samples (n = 159) of WEEE in the metropolitan region of Sorocaba, Sao Paulo, Brazil. PBDEs were detected in 149 samples, with concentrations in 18 samples exceeding the European Union's Low POP Content Limit (LPCL) of 1000 mg/kg. Decabromodiphenyl ether (BDE-209) was the congener present at the highest concentration in most samples, with those of other PBDEs such as BDE-47 much lower. In general, samples containing >1000 mg/kg are those categorised as display items and miscellaneous EEE (n = 15.27 %), comprising: parts from cathode ray tube TVs (n = 11), audio systems (n = 2), and LCD TVs (n = 2). In addition, in 5 % (n = 3) of IT and telecommunications equipment samples (computer parts) PBDE concentrations exceeded 1000 mg/kg. Our results show the need for greater control and monitoring of the presence of these pollutants in WEEE before recycling and final disposal, to prevent PBDEs entering the recycling stream.

The European Regulatory Strategy for flame retardants - The right direction but still a risk of getting lost

Flame retardants (FRs) are a major group of chemicals used to protect against fast developing fires and comply with fire regulations. Many of them have a negative impact on the environment and human health. Some have been phased out, but the vast majority remain on the market including a substantial number of harmful ones. The European Chemicals Agency (ECHA) presented a strategy to phase out harmful flame retardants, based on a group approach. While this approach will help to finally overcome the loop of banning individual chemicals, which are then replaced by similar ones, which need to be banned again, the proposed strategy also contains several flaws, which may inadvertently weaken the strategy. A stronger grouping system is discussed and proposed, in which additional criteria for the evaluation of FRs as groups are included, e.g., more attention for toxic effects, mobility, recyclability and waste production. This discussion paper is intended to contribute to a sustainable approach as proposed in the European Chemicals Sustainability Strategy. It should also help create a truly circular economy.

Chemical characteristics of artificial plastic plants and the presence of hazardous elements from the recycling of electrical and electronic waste

Because of their convenience, the demand for decorative plastic plants has been increasing over recent years. However, no information exists on the origin or nature of the polymers employed or the type of additives used in order to understand potential environmental impacts and inform safe and sustainable disposal or recycling practices. In this study, 203 parts or offcuts from 175 plastic plants acquired from European shops and venues have been analysed by X-ray fluorescence spectrometry to determine elemental content, while a selection has been analysed by infrared spectrometry to establish polymer type. The (usually green) moulded components (n = 159) were commonly constructed of polyethylene or polypropylene, while leaves and colourful petals (n = 40) were generally made of polyethylene terephthalate fabric that had been glued to the moulded component. However, both components also exhibited evidence of being coated with a resin or adhesive for support, protection or appearance. Barium, Fe, Ti and Zn-based additives were commonly encountered but more important from an environmental and health perspective were variable concentrations of potentially hazardous elements in the moulded parts: namely, Br (6.1 to 108,000 mg kg-1; n = 78), Pb (7.6 to 17,400 mg kg-1; n = 53) and Sb (58.6 to 70,800 mg kg-1; n = 17). These observations suggest that many of the moulded components are derived from recyclates that are contaminated by waste electronic and electrical plastic, introducing brominated flame retardants, the flame retardant synergist, Sb2O3, and Pb into the final product. There are no standards for these chemicals in plastic plants, but regulations for electronic plastic, toy safety and packaging are frequently exceeded or potentially exceeded. Widespread contamination of plastic plants may impose constraints on their recycling and disposal.

Occurrence of hexabromocyclododecanes (HBCDs) and tetrabromobisphenol A (TBBPA) in indoor dust from different microenvironments: levels, profiles, and human exposure

The levels and distributions of hexabromocyclododecane diastereoisomers (HBCDs) (including α, β, and γ-HBCD) and tetrabromobisphenol A (TBBPA) were investigated in indoor dust from bedrooms and offices. HBCDs diastereoisomers were the most abundant compounds in the dust samples, and the concentrations of ∑HBCDs in the bedrooms and offices ranged from 10.6 to 290.1 ng/g and 17.6 to 1521.9 ng/g, respectively. The concentrations of target compounds in the offices were generally higher than those in the bedrooms, probably due to the presence of more electrical equipment in the offices. In this study, highest levels of target compounds were all found in the electronics. In the bedrooms, the highest mean level of ∑HBCDs was found in air conditioning filter dust (118.57 ng/g), while the personal computer table surface dust showed the peak mean concentrations of ∑HBCDs (290.74 ng/g) and TBBPA (539.69 ng/g) in the offices. Interestingly, a significantly positive correlation was observed between the concentrations of ∑HBCDs in windowsills and beddings dust in the bedrooms, suggesting beddings was one of the crucial sources of ∑HBCDs in the bedrooms. The high dust ingestion values of ∑HBCDs and TBBPA were 0.046 and 0.086 ng/kg bw/day for adults, while 0.811 and 0.04 ng/kg bw/day for toddlers, respectively. The high dermal exposure values of ∑HBCDs were 0.026 and 0.226 ng/kg bw/day for adults and toddlers, respectively. Except for dust ingestion, other human exposure pathways (such as the dermal contact with beddings and furniture) should be paid attention.

A Rapid Screening Method for the Detection of Additives in Electronics and Plastic Consumer Products Using AP-MALDI-qTOF-MS

A novel method was developed and optimized for the fast-screening analysis of additives in electronics and plastic consumer products using atmospheric pressure matrix-assisted laser desorption ionization (AP-MALDI) coupled with a high-resolution quadrupole time-of-flight (qTOF) mass spectrometer (MS). To simplify sample preparation and increase sample throughput, an innovative 48 well graphene nanoplatelets (GNP) doped AP-MALDI target plate was developed. The GNP incorporated in the target plate fulfilled the role of the MALDI matrix and, therefore, sample extracts could be directly transferred to the AP-MALDI 48 well target plate and analyzed without a subsequent matrix addition. The homogeneously dispersed and immobilized GNP target plates also provided increased signal intensity and reproducibility. Furthermore, analytical standards of various plastic additives and plastic products with known concentrations of additives were studied to assess the AP-MALDI ionization mechanisms and method capability. The analysis time was 15 s per measurement using an automated sequence. The GNP-doped target plates exhibited high desorption/ionization of low molecular weight molecules (<1000 Da) and can be used in both positive and negative ionization modes. The AP-MALDI-qTOF-MS method was applied to screen for additives in various electronics and plastic consumer products. Suspect screening was performed using a database containing 1366 compounds. A total of 56 additives including antioxidants, flame retardants, plasticizers, UV-stabilizers, and UV-filters were identified (confidence level 4). Identification of certain plastic additives in plastic children's toys may indicate that they are recycled from waste electronic and electronic equipment (WEEE).

POP-BFRs in consumer products: Evolution of the efficacy of XRF screening for legislative compliance over a 5-year interval and future trends

In 2015-16, a study of approximately 500 waste plastic articles showed that portable X-ray fluorescence (XRF) was up to 95 % effective in screening for compliance with low persistent organic pollutant (POP) concentration limits (LPCLs) on brominated flame retardants (BFRs) in waste. The present study conducted in 2019-20 mirrors that conducted five years prior on a similar number and range of articles, testing the hypothesis that increased use of alternative BFRs as replacements for POP-BFRs will reduce the effectiveness of XRF as a tool for monitoring compliance with LPCLs. In comparing the results, the overall screening efficacy for LPCL compliance reduced from ~95 % to ~88 %, due in part to decreased prevalence of POP-BFRs and potentially increased presence of alternative flame retardants, particularly in goods with shorter lifecycles such as electronics. We additionally examined the impacts of a number of modifications to the XRF measurement protocol on its efficacy, including: using elemental Sb as a qualifier in detecting POP-BFRs in hard plastics; reduced XRF analysis time; and the elimination of background interference using a test stand. The rate at which hard plastics from electronic waste may be analysed by XRF can be substantially improved by reducing analysis time to 5 s, with minimal increase in false exceedances of the LPCL. Monitoring Sb does not appear an effective qualifier for the presence of POP-BFRs, as Sb seems to be used with a range of BFRs. Use of the test stand, while reducing interference, appeared to reduce accuracy when screening low density and thin samples. Despite a seeming increased use of alternative BFRs, screening of waste for compliance with LPCLs using rapid and low-cost screening methods such as portable XRF is still necessary as methods such as GC-MS cannot be scaled up to match the quantities of waste requiring screening.

PBDEs in the marine environment: Sources, pathways and the role of microplastics

Brominated flame retardants (BFRs) are an important group of additives in plastics that increase resistance to ignition and slow down the rate of burning. Because of concerns about their environmental and human health impacts, however, some of the most widely employed BFRs, including hexabromocyclododecane (HBCD) and commercial mixtures of penta-, octa- and deca- (poly)bromodiphenyl ethers (PBDEs), have been restricted or phased out. In this review, the oceanic sources and pathways of PBDEs, the most widely used BFRs, are evaluated and quantified, with particular focus on emissions due to migration from plastics into the atmosphere versus emissions associated with the input of retarded or contaminated plastics themselves. Calculations based on available measurements of PBDEs in the environment suggest that 3.5 and 135 tonnes of PBDEs are annually deposited in the ocean when scavenged by aerosols and through air-water gas exchange, respectively, with rivers contributing a further ∼40 tonnes. Calculations based on PBDE migration from plastic products in use or awaiting or undergoing disposal yield similar net inputs to the ocean but indicate a relatively rapid decline over the next two decades in association with the reduction in the production and recycling of these chemicals. Estimates associated with the input of PBDEs to the ocean when "bound" to marine plastics and microplastics range from about 360 to 950 tonnes per year based on the annual production of plastics and PBDEs over the past decade, and from about 20 to 50 tonnes per annum based on the abundance and distribution of PBDEs in marine plastic litter. Because of the persistence and pervasiveness of plastics in the ocean and diffusion coefficients for PBDEs on the order of 10^-20 to 10^-27 m² s^-1, microplastics are likely to act as a long-term source of these chemicals though gradual migration. Locally, however, and more important from an ecotoxicological perspective, PBDE migration may be significantly enhanced when physically and chemically weathered microplastics are exposed to the oily digestive fluids conditions of fish and seabirds.

Review of the environmental occurrence, analytical techniques, degradation and toxicity of TBBPA and its derivatives

BFRs (brominated flame retardants) are a class of compounds that are added to or applied to polymeric materials to avoid or reduce the spread of fire. Tetrabromobisphenol A (TBBPA) is one of the known BFR used many in industries today. Due to its wide application as an additive flame retardant in commodities, TBBPA has become a common indoor contaminant. Recent researches have raised concerns about the possible hazardous effect of exposure to TBBPA and its derivatives in humans and wildlife. This review gives a thorough assessment of the literature on TBBPA and its derivatives, as well as environmental levels and human exposure. Several analytical techniques/methods have been developed for sensitive and accurate analysis of TBBPA and its derivatives in different compartments. These chemicals have been detected in practically every environmental compartment globally, making them a ubiquitous pollutant. TBBPA may be subject to adsorption, biological degradation or photolysis, photolysis after being released into the environment. Treatment of TBBPA-containing waste, as well as manufacturing and usage regulations, can limit the release of these chemicals to the environment and the health hazards associated with its exposure. Several methods have been successfully employed for the treatment of TBBPA including but not limited to adsorption, ozonation, oxidation and anaerobic degradation. Previous studies have shown that TBBPA and its derivative cause a lot of toxic effects. Diet and dust ingestion and have been identified as the main routes of TBBPA exposure in the general population, according to human exposure studies. Toddlers are more vulnerable than adults to be exposed to indoor dust through inadvertent ingestion. Furthermore, TBBP-A exposure can occur during pregnancy and through breast milk. This review will go a long way in closing up the knowledge gap on the silent and over ignored deadly effects of TBBPA and its derivatives and their attendant consequences.

Direct reuse of electronic plastic scraps from computer monitor and keyboard to direct stem cell growth and differentiation

Reuse of electronic wastes is a critical aspect for a more sustainable circular economy as it provides the simplest and most direct route to extend the lifespan of non-renewable resources. Herein, the distinctive surface and micro topographical features of computer electronic-plastic (E-plastic) scraps were unconventionally repurposed as a substrate material to guide the growth and differentiation of human adipose-derived mesenchymal stem cells (ADSCs). Specifically, the E-plastics were scavenged from discarded computer components such as light diffuser plate (polyacrylates), prismatic sheet (polyethylene terephthalate), and keyboards (acrylonitrile butadiene styrene) were cleaned, sterilized, and systematically characterized to determine the identity of the plastics, chemical constituents, surface features, and leaching characteristics. Multiparametric analysis revealed that all the E-plastics could preserve stem-cell phenotype and maintain cell growth over 2 weeks, rivalling the performance of commercial tissue-culture treated plates as cell culture plastics. Interestingly, compared to commercial tissue-culture treated plastics and in a competitive adipogenic and osteogenic differentiation environment, ADSCs cultured on the keyboard and light diffuser plastics favoured bone cells formation while the grating-like microstructures of the prismatic sheet promoted fat cells differentiation via the process of contact guidance. Our findings point to the real possibility of utilizing discarded computer plastics as a "waste-to-resource" material to programme stem cell fate without further processing nor biochemical modification, thus providing an innovative second-life option for E-plastics from personal computers.

Recycling plastics containing decabromodiphenyl ether into new consumer products including children's toys purchased in Japan and seventeen other countries

Polybrominated diphenyl ethers (PBDEs) are flame retardants widely used to manufacture several commercial plastic products. The major homologue in commercial PBDE mixtures are listed in the Stockholm Convention on Persistent Organic Pollutants and are scheduled for global elimination. Hence, to understand more about unintentional contamination of plastic recycling stream by restricted PBDEs, we examined 540 small plastic consumer products (1139 components after dismantling), including children's toys, purchased in 18 countries (mainly Japan) between 2015 and 2019. Handheld X-ray fluorescence analysis revealed that 219 plastic components (19% of the total samples) contained bromine at a concentration of ≥30 mg kg^-1. Chemical analysis of these bromine-positive components revealed that 109 pieces (9.6% of the total), mainly those made of black-colored plastic, contained PBDEs at concentrations ranging between 35 and 10,000 mg kg^-1, with the maximum contribution from decabromodiphenyl ether (decaBDE). These PBDE concentrations were insufficient to impart flame retardancy, suggesting that the recycled plastic used to manufacture these consumer products probably originated from electronic waste, the manufacture of which was the primary use of commercial decaBDE mixtures. PBDEs were also found in secondary raw plastic materials and their final products obtained in India in 2019, demonstrating that plastics containing decaBDE end up in products where they serve no functional purpose. To contribute to the circular economy, the recycling of plastic waste in end-of-life products should be promoted. However, urgent action is needed to prevent plastic additives of concern, including PBDEs, from entering new products used in daily lives, particularly those used by children.

Recycling Plastics from WEEE: A Review of the Environmental and Human Health Challenges Associated with Brominated Flame Retardants

Waste electrical and electronic equipment (WEEE) presents the dual characteristic of containing both hazardous substances and valuable recoverable materials. Mainly found in WEEE plastics, brominated flame retardants (BFRs) are a component of particular interest. Several actions have been taken worldwide to regulate their use and disposal, however, in countries where no regulation is in place, the recovery of highly valuable materials has promoted the development of informal treatment facilities, with serious consequences for the environment and the health of the workers and communities involved. Hence, in this review we examine a wide spectrum of aspects related to WEEE plastic management. A search of legislation and the literature was made to determine the current legal framework by region/country. Additionally, we focused on identifying the most relevant methods of existing industrial processes for determining BFRs and their challenges. BFR occurrence and substitution by novel BFRs (NBFRs) was reviewed. An emphasis was given to review the health and environmental impacts associated with BFR/NBFR presence in waste, consumer products, and WEEE recycling facilities. Knowledge and research gaps of this topic were highlighted. Finally, the discussion on current trends and proposals to attend to this relevant issue were outlined.

Estimating mouthing exposure to chemicals in children's products

BACKGROUND

Existing models for estimating children's exposure to chemicals through mouthing currently depends on the availability of chemical- and material-specific experimental migration rates, only covering a few dozen chemicals.

OBJECTIVE

This study objective is hence to develop a mouthing exposure model to predict migration into saliva, mouthing exposure, and related health risk from a wide range of chemical-material combinations in children's products.

METHODS

We collected experimental data on chemical migration from different products into saliva for multiple substance groups and materials, identifying chemical concentration and diffusion coefficient as main properties of influence. To predict migration rates into saliva, we adapted a previously developed migration model for chemicals in food packaging materials. We also developed a regression model based on identified chemical and material properties.

RESULTS

Our migration predictions correlate well with experimental data (R2 = 0.85) and vary widely from 8 × 10-7 to 32.7 µg/10 cm2/min, with plasticizers in PVC showing the highest values. Related mouthing exposure doses vary across chemicals and materials from a median of 0.005 to 253 µg/kgBW/d. Finally, we combined exposure estimates with toxicity information to yield hazard quotients and identify chemicals of concern for average and upper bound mouthing behavior scenarios.

SIGNIFICANCE

The proposed model can be applied for predicting migration rates for hundreds of chemical-material combinations to support high-throughput screening.

Calculation and Experimental Validation of a Novel Approach Using Solubility Parameters as Indicators for the Extraction of Additives in Plastics

Accurately quantifying chemical additives with adverse health effects in plastic products is critical for environmental safety and risk assessment. In this work, a novel approach using solubility parameters (δ) as indicators for the extraction of additives in plastics was developed. The mechanism was evaluated by using 10 organic solvents with different solubility parameters to extract brominated flame-retardant-decabrominated diphenyl ether (BDE-209) in polyethylene (PE), polypropylene (PP), and polyethylene terephthalate (PET). Certified reference materials (CRMs) or CRM candidate materials were applied as matrix materials. The extracted BDE-209 and solubility parameters of solvents could fit into a curve of a quadratic function. The value of abscissa corresponding to the vertex of the function was close to the solubility parameter of plastic calculated by the group contribution method (Δδ < 0.37). Toluene, n-hexane, and acetone were the solvents with high extraction efficiency for PE, PP, and PET, confirming the feasibility of the developed approach. The results of ethyl acetate and acetone indicated the high weight of functional groups affecting the dissolution behavior. The developed approach was further verified by analyzing penta-/octa-BDE and phthalate esters in PET and polyvinyl chloride (PVC) and finally applied to analyze 15 plastic products made of PP, PE, PET, polystyrene, and PVC. The detected tetrabromodiphenyl ether (BDE-47), BDE-209, decabromodiphenyl ethane, and di(2-ethylhexyl) terephthalate all matched the approach and verified its practicability for field sample analysis.

Assessment of brominated flame retardants in a small mixed waste electronic and electrical equipment (WEEE) plastic recycling stream in the UK

Identifying the presence of brominated flame retardants (BFRs) within individual polymer types prior to extrusion has given us a unique perspective on which polymers may be problematic in meeting European Union (EU) low persistent organic pollutant (POP) content limits (LPCLs) and the potential for mixed engineering plastics (MEP) to be used as a viable recycled product. Our findings suggest that careful management of the polymer types within the feed chips prior to extrusion could deliver extruded polymer pellets that meet the EU LPCL values for POP-BFRs (i.e. <1000 mg/kg). Within this study, three fractions of extruded polymer pellets ("light", "medium", and "heavy" MEP) were created using density separation. Each fraction was characterised for 28 legacy and novel BFRs with brominated diphenyl ether-209 (BDE-209) (68-37,000 mg/kg) and tetrabromobisphenol-A (TBBP-A) (17-120,000 mg/kg) both predominant and ubiquitous. Portable X-ray fluorescence (XRF) was utilised to measure Br in 120 individual MEP chips of various polymer types. Those chips that XRF flagged as having high Br concentrations (>2500 mg/kg) were subjected to further evaluation for BFR content via mass spectrometry analysis and the results compared with the XRF Br data. This revealed that in 22% of the 120 chips studied, XRF incorrectly identified the LPCL to be exceeded. Our data also identifies the presence of the novel BFRs decabromodiphenyl ethane (DBDPE) and 1,2-bis(2,4,6-tribromophenoxy) ethane (BTBPE) in plastics derived from waste electronic and electrical equipment (WEEE). While the "light-MEP" samples contained POP-BFR concentrations below LPCLs, the "medium-MEP" and "heavy-MEP" fractions exceeded such limits. Management of the polymer chips by colour sorting resulted in significant reductions in concentrations of all BFRs in the clear polymers such that LPCL limits were not exceeded; however, concentration reductions in white polymers were insufficient to meet LPCLs.

Evaluation of polybrominated diphenyl ether (PBDE) flame retardants from various materials in professional seating furnishing wastes from French flows

Polybrominated diphenyl ethers (PBDEs) are brominated flame retardants that are used in polymeric materials. Due to their adverse health effects, the use of recycled wastes has been forbidden if the total PBDE content exceeds 0.1% (w/w). The objective was to estimate the proportion of PBDEs in professional seating furnishing wastes to identify the materials in which the content of PBDEs (and particularly BDE-209) could exceed the limit to eliminate them from recycling. An analytical process (microwave extraction followed by purification and chromatographic analysis) was adapted to assess with a unique methodology the amounts of eight PBDEs in materials that result from various seating wastes, such as hard plastics, foams and accompanying textiles. X-ray fluorescence (XRF) was used to rapidly predict critical PBDE concentrations via Br. From 100 samples, the total PBDE content did not exceed the current tolerated threshold. The examined materials contained only trace levels of former PBDE formulations, and BDE-209 was identified at higher amounts, mainly in hard plastics, but these amounts were less than 312 mg kg^-1. Since XRF was not reliable for quantitative measurements and was not specific, no direct correlation could be identified between Br and PBDE levels. Br was strongly associated with As in all the materials, but the presence of PBDEs was not clearly associated with the presence of other metals that are used in flame retardants.

Impact of "healthier" materials interventions on dust concentrations of per- and polyfluoroalkyl substances, polybrominated diphenyl ethers, and organophosphate esters

Per- and polyfluoroalkyl substances (PFAS), polybrominated diphenyl ethers (PBDEs), and organophosphate esters (OPEs) are found in building materials and associated with thyroid disease, infertility, and impaired development. This study's objectives were to (1) compare levels of PFAS, PBDEs, and OPEs in dust from spaces with conventional versus "healthier" furniture and carpet, and (2) identify other product sources of flame retardants in situ. We measured 15 PFAS, 8 PBDEs, and 19 OPEs in dust from offices, common areas, and classrooms having undergone either no intervention (conventional rooms in older buildings meeting strict fire codes; n = 12), full "healthier" materials interventions (rooms with "healthier" materials in buildings constructed more recently or gut-renovated; n = 7), or partial interventions (other rooms with at least "healthier" foam furniture but more potential building contamination; n = 28). We also scanned all materials for bromine and phosphorus as surrogates of PBDEs and OPEs respectively, using x-ray fluorescence. In multilevel regression models, rooms with full "healthier" materials interventions had 78% lower dust levels of PFAS than rooms with no intervention (p < 0.01). Rooms with full "healthier" interventions also had 65% lower OPE levels in dust than rooms with no intervention (p < 0.01) and 45% lower PBDEs than rooms with only partial interventions (p < 0.10), adjusted for covariates related to insulation, electronics, and furniture. Bromine loadings from electronics in rooms were associated with PBDE concentrations in dust (p < 0.05), and the presence of exposed insulation was associated with OPE dust concentrations (p < 0.001). Full "healthier" materials renovations successfully reduced chemical classes in dust. Future interventions should address electronics, insulation, and building cross-contamination.

Brominated and phosphate flame retardants from interior and surface dust of personal computers: insights into sources for human dermal exposure

It remains unclear whether internal or external sources play the more significant role in flame retardant (FR) contamination of surface dust from personal computers (PCs), which may lead to bias on dermal exposure assessment of FRs. In the present study, the occurrence and profiles of several brominated and phosphate FRs were measured in the interior dust, and the upper surface (keyboard) and bottom surface (bottom cover) wipes of PCs. BDE 209 (639 ng/g), decabromodiphenyl ethane (DBDPE, 885 ng/g), and triphenyl phosphate (TPHP, 1880 ng/g) were the most abundant chemicals in interior PC dust, while tris(2-chloroisopropyl) phosphate (TCIPP), TPHP, and DBDPE were dominant on both surfaces of PCs. No significant correlation between interior dust and both PC surfaces was observed for concentrations of most FRs except BDE 183. Different sources of FRs for interior and surface dust of PCs were further revealed by principal component analysis (PCA). FRs from external sources, rather than emission from inner PC components, are likely the main contributor for FR profiles on PC surfaces. Exposure assessment results demonstrated a minor contribution from PC dermal contact, compared with hand-to-mouth uptake, to total exposure. The applicability of surface wipes to assess dermal exposure to FR-treated products needs to be further investigated.

Chemicals of concern in plastic toys

We present a list of Chemicals of Concern (CoCs) in plastic toys. We started from available studies reporting chemical composition of toys to group plastic materials, as well as to gather mass fractions and function of chemicals in these materials. Chemical emissions from plastic toys and subsequent human exposures were then estimated using a series of models and a coupled near-field and far-field exposure assessment framework. Comparing human doses with reference doses shows high Hazard Quotients of up to 387 and cancer risk calculated using cancer slope factors of up to 0.0005. Plasticizers in soft plastic materials show the highest risk, with 31 out of the 126 chemicals identified as CoCs, with sum of Hazard Quotients >1 or child cancer risk >10^-6. Our results indicate that a relevant amount of chemicals used in plastic toy materials may pose a non-negligible health risk to children, calling for more refined investigations and more human- and eco-friendly alternatives. The 126 chemicals identified as CoCs were compared with other existing regulatory prioritization lists. While some of our chemicals appear in other lists, we also identified additional priority chemicals that are not yet covered elsewhere and thus require further attention. We finally derive for all considered chemicals the maximum Acceptable Chemical Content (ACC) in the grouped toy plastic materials as powerful green chemistry tool to check whether chemical alternatives could create substantial risks.

Polystyrene foam as a source and sink of chemicals in the marine environment: An XRF study

Polystyrene foam (expanded and extruded polystyrene: EPS and XPS, respectively) is a ubiquitous and pervasive type of marine plastic whose physical properties, transport and fate are distinctly different to those of other common (unfoamed) types of thermoplastic litter. In this study, a range of fragments of EPS and XPS retrieved from three beaches in southwest England have been characterised by energy-dispersive X-ray fluorescence (XRF) spectrometry in order to examine the chemical makeup and potential biological and geochemical impacts and interactions of this type of plastic waste. Analyses performed through sample faces and, in some cases and after dissection, through the material core, revealed variable concentrations of Fe, Ti and Zn among the fragments and, in many instances, within the same sample. This likely reflects the presence of reaction residues and pigments arising from the manufacture of polystyrene, and, for Fe and Ti, significant and heterogeneous ion and mineral acquisition from the environment during transport in suspension or while beached. Acquired oxides of Fe are partly responsible for the chemical fouling observed on the face of most samples and are able to act as an adsorbent for other metals, like Pb. Detection of Br in many fragments up to concentrations of 11,500 mg kg^-1 likely results from the incorporation of the flame retardant, hexabromocyclododecane, in EPS and XPS designed for (but not necessarily limited to) the construction sector. These observations suggest that EPS and XPS can act as both a source and sink for contaminants in the marine environment that merit further investigation.

Phasing-out of legacy brominated flame retardants: The UNEP Stockholm Convention and other legislative action worldwide

Due to their toxicity and persistence, several families of brominated flame retardants (BFRs) have been listed as persistent organic pollutants (POPs) in the Stockholm Convention, a multilateral treaty overseen by the United Nations Environment Programme. This treaty mandates that parties who have signed must take administrative and legislative actions to prevent the environmental impacts that POPs pose, both within their jurisdictions and in the global environment. The specific BFRs listed in the Stockholm Convention are Polybrominated Diphenyl Ethers (PBDEs), Hexabromocyclododecane (HBCDD), and Hexabromobiphenyl (HBB), chemicals which must therefore be heavily restricted within the jurisdictions of the signatories. As an example, within the EU, hexabromobiphenyl (HBB), the PBDE commercial mixtures, and HBCDD are almost entirely prohibited in terms of both production and use in commercial goods. Waste articles containing excess concentrations of these BFRs are similarly restricted and must be disposed of in a manner that destroys or irreversible transforms the BFR in question. In some cases, specific exemptions for these limits are defined by the Convention for certain parties: for example, Penta- and Octa-BDE can be present in waste materials for recycling until 2030, while Deca-BDE can be applied to some aviation and automotive applications until 2036. However, in such cases, very specific criteria and guidelines apply for their use and/or production. Worldwide, China, Japan, India, and the United States of America have made significant advances in the regulation of POPs, in line with the provisions of the Stockholm Convention. China has established concentration limits for Penta- and Octa-BDEs in electronic goods. It is also currently availing of an exemption to allow for the use of HBCDD and has not yet ratified the Convention with regards to Deca-BDE. Japan meanwhile has classified HBB and Penta-/Octa-BDE compounds as Class I Specified Chemical Substances which virtually prohibits the manufacture, import, and use of these chemicals in all applications. India has banned the manufacture, trade, import, and use of HBB, HBCDD and some PBDEs, and has established concentration limits for all PBDEs in certain electrical goods. Finally, the United States has no federal mandate for the restriction of POPs and has not ratified the annexes to the Convention requiring them to do so. However, thirteen states have implemented their own state-wide concentration limits on a variety of flame retarding chemicals in various commercial applications. Though these limits worldwide are a very positive step for the removal of POP-BFRs from the environment, the increased use of replacement flame retardants renders such legislation only partially effective. The lack of effective screening mechanisms in waste management facilities means that BFR-treated plastics can be inadvertently recycled and remain in circulation. The rise in the use of novel BFRs (NBFRs) can furthermore hinder screening methods currently being developed and the additives themselves may pose similar issues to their predecessors owing to their similar chemical properties. Thus, restrictions on current BFRs will result in the use of new flame retardants, which may in turn be banned and replaced once again. Further research into and development of methods to screen for hazardous chemicals in end of life materials is therefore of the utmost importance. This must be coupled with pro-active legislation that eliminates the need for using such persistent and potentially harmful chemicals in the future.

Polybrominated diphenyl ethers in plastic waste of electrical and electronic equipment: a case study in Belarus

Plastic waste of electrical and electronic equipment (WEEE) can contain polybrominated diphenyl ethers (PBDEs) that have been used as fire retardants for a long time. PBDEs were listed in the Stockholm Convention as persistent organic pollutants, so PBDE-containing plastic waste should be separated and disposed of in an ecologically sound manner. In the article, the results of bromine and PBDE content in plastic samples of WEEE collected in Belarus are presented. The screening method for bromine identification and HRGC/HRMS for PBDE identification were applied. It is shown that bromine is present in 43% of the 111 studied samples. Most often, Br-containing plastic was found in CRT monitor, CRT TVs and LCD monitor (about 50%), printers (35%), and LCD TVs (25%). PBDEs were revealed in 12 Br-containing samples, representing TVs, monitors, and printers. The sum of ∑10PBDEs varied from 6.6 to 21,000 μg/kg. BDE-209 dominated in 9 samples (75% of cases); BDE-183, in two; and BDE-47 and BDE-99, in one sample. Based on the low content of PBDEs in the plastic, year of equipment production, and year of restriction of PBDEs applied in the countries-manufacturers, it was concluded that the presence of PBDEs in plastic is a consequence of contaminated waste recycling. Despite the relatively low concentrations of PBDEs (below the limit values established by the Stockholm and Basel conventions for POP wastes), further research is necessary with an extension of the list of analyzed types of equipment and identification of other brominated flame retardants.

Migration characteristics of heavy metals during simulated use of secondary products made from recycled e-waste plastic

Recycling of plastics from e-waste can conserve resources, however, aging during the use of plastic products can cause the migration of heavy metals in additives. This study presents a methodology for evaluating the risks of heavy metals in waste plastic secondary products during long term use associated with heavy metal migration. The study processes were investigated by: (1) recycling waste plastics and producing secondary products; (2) thermal aging of secondary products; and (3) toxic leaching used to quantitatively analyse the dissolution of heavy metals. Combined with the changes in mechanical properties and microstructure, the effect of aging on the migration of heavy metals was observed. The results showed that the polymer appeared to delaminate, the adhesion of waste plastics to additives decreased, and the mechanical properties clearly decreased after the thermal aging experiment. Leaching experiments showed that the leached concentrations of Ni, Cu, Zn, Pb, and Sb in the three types waste plastic products increased over time. After 8 d of aging, the leached concentrations of Ni, Sb, and Pb exceeded the third, fourth, and third class of the groundwater quality standard, respectively. Specifically, the concentrations of Sb were 141, 289, and 21.1 times higher than the maximum permissible level. Therefore, management hierarchy and safe environmental recycling methods should be developed to reduce the risk of heavy metals in waste plastic secondary products.

Assessment of tetrabromobisphenol-A (TBBPA) content in plastic waste recovered from WEEE

Due to the variability of additives and polymer types used in electrical and electronic equipment (EEE), and in accordance with the European Directive 2012/19/EU, an implementation of sound management practices is necessary. This work focuses on assessing the content of tetrabromobisphenol-A (TBBPA) in acrylonitrile-butadiene-styrene (ABS), polypropylene (PP), polycarbonate (PC) and their polymer blends (i.e. PC/ABS). A total of 36 plastic housing samples originating from microwave ovens, electric irons, vacuum cleaners and DVD/CD players were subjected to microwave-assisted-extraction (MAE) and/or ultrasound-assisted-extraction (UAE). Maximum mean concentration values of TBBPA measured in DVD/CD players and vacuum cleaners ranged between 754-1146 μg/kg, and varied per polymer type, as follows: 510-2515 μg/kg in ABS and 55-3109 μg/kg in PP. The results indicated that MAE was more sufficient than UAE in the extraction of TBBPA from ABS. To optimize the UAE procedure, various solvents were tested. Higher amounts of TBBPA were obtained from ABS and PP using a binary mixture of a polar-non-polar solvent, isopropanol:n-hexane (1:1), whereas the sole use of isopropanol exhibited incomplete extraction.

Investigation of the heterogeneity of bromine in plastic components as an indicator for brominated flame retardants in waste electrical and electronic equipment with regard to recyclability

Waste electrical and electronic equipment (WEEE) can contain brominated flame retardants (BFRs) that pose a threat to human health and the environment. In addition, Br-containing plastics reduce the recycling potential of WEEE. In order to gain a better insight into the distribution of Br in plastics from WEEE, the total concentration of Br was measured on the level of device types and plastic components using handheld X-ray fluorescence (hXRF). In 35 % of the sample size (882 components from 369 different devices, which originate from 6 device types) Br was detected, 5 % exceeded the RoHS limit. Only few and older devices contained high Br concentrations, while the majority were below the RoHS limit and could be recycled. In addition, 18 different plastic types were identified by infrared spectroscopy, with acrylonitrile butadiene styrene being the most abundant (44 % of all samples). Manual dismantling of devices into individual plastic components enabled us to examine Br hotspots and the variety of plastic types in WEEE. Based on this analytical procedure, WEEE recyclers could exclude certain equipment or plastic components (e.g. power supplies or PC housings) directly on-site prior to WEEE recycling and shredding in order to produce high-quality recycled products and avoid cross-contamination.

Monitoring the levels of brominated and organophosphate flame retardants in passenger cars: Utilisation of car air filters as active samplers

Filters in residential and office air conditioning (A/C) systems have been used as sampling devices for monitoring different pollutants. However, cabin air filters (CAFs) in the A/C system of passenger cars have not been utilised for this purpose. In this study, we collected 22 used CAFs from passenger cars in Hanoi, Vietnam to analyse for 8 polybrominated diphenyl ethers (PBDEs) and 10 organophosphate esters (OPEs). All the analytes were detected in more than 50% of samples with the exception of BDE153 and BDE154. The average concentrations of ∑₁₀OPEs and ∑₈BDEs in the captured dust were 2600 and 40 ng/g, respectively with Tris (1-chloro-2-propyl) phosphate (TCIPP) and BDE209 as the dominant congener in OPE and BDE groups, respectively. CAFs are a potential tool to qualitatively assess the levels of semi-volatile chemicals in suspended dust in cars as a screening step for exposure assessment of those chemicals.

MIR spectral characterization of plastic to enable discrimination in an industrial recycling context: II. Specific case of polyolefins

Sorting at industrial scale is required to perform mechanical recycling of plastics in order to obtain properties that could be competitive with virgin polymers. As a matter of fact, the most part of the various types of plastic waste are not miscible and even compatible. Mid-Infrared (MIR) HyperSpectral Imagery (HSI) is viewed as one of the solutions to the problem of black plastic sorting. Many Waste of Electrical and Electronic Equipment (WEEE) plastics are black. Nowadays, these materials are difficult to sort at an industrial scale because the main used pigment to produce this color, carbon black, masks the Near-Infrared (NIR) spectra of polymers, the currently most used technology for acute sorting in industrial conditions. In this study, laboratory Fourier-Transform Infrared (FTIR) in Attenuated Total Reflection mode (ATR) has been used as a theoretical toolbox based on physical chemistry to help building an automated HSI discrimination despite its limited conditions, especially shorter wavelengths ranges. Weaker resolution and very short acquisition times are other HSI limitations. Helping fast and exhaustive laboratory characterizations of polymeric waste stocks is the other goal of this study. This study focusses on polyolefins as they represent the second biggest fraction of WEEE plastics (WEEP) after styrenics and since little quantities mixed to styrenics during mechanical recycling can lead to important decrease in mechanical properties. Twelve references were thus evaluated and compared between each other and with real waste samples to highlight spectral elements, which can enable differentiation. Charts compiling the signals of discussed polymers were built aiming to the same objective.

Are cell phones an indicator of personal exposure to organophosphate flame retardants and plasticizers?

BACKGROUND

Exposure to organophosphate ester (OPE) flame retardants and plasticizers is widespread and is of concern due to their toxicity.

OBJECTIVES

To investigate relationships between and within OPE concentrations in air, dust, hands, electronic product wipes and urinary metabolites with the goal of identifying product sources and exposure pathways.

METHODS

Women in Toronto and Ottawa, Canada, provided a urine sample, two sets of hand wipes, access to their homes for air and dust sampling, and completed a questionnaire. OPE concentrations were obtained for air and floor dust in the bedroom (n = 51) and most used room (n = 26), hand wipes (n = 204), and surface wipes of handheld (n = 74) and non-handheld electronic devices (n = 125). All air, dust and wipe samples were analyzed for 23 OPE compounds; urine samples (n = 44) were analyzed for 8 OPE metabolites.

RESULTS

Five-8 OPEs were detected in >80% of samples depending on the sample type. OPE median concentrations in hand wipes taken 3 weeks apart were not significantly different. Palms had higher concentrations than the back of hands; both were significantly correlated. Concentrations of 9 OPEs were significantly higher in surface wipes of handheld than non-handheld electronic devices. Six OPEs in hand wipes were significantly correlated with cell phone wipes, with two to four OPEs significantly correlated with tablet, laptop and television wipes. Multiple regression models using hand wipes, cell phone wipes and dust explained 8-33% of the variation in creatinine-adjusted urinary metabolites; air concentrations did not have explanatory power. OPEs in cell phone wipes explained the greatest variation in urinary metabolites.

CONCLUSIONS

Handheld electronic devices, notably cell phones, may either be sources or indicators of OPE exposure through hand-to-mouth and/or dermal uptake.

Phthalates and organophosphates in settled dust and HVAC filter dust of U.S. low-income homes: Association with season, building characteristics, and childhood asthma

Phthalates and organophosphates are ubiquitous indoor semi-volatile organic contaminants (SVOCs) that have been widely used as plasticizers and flame retardants in consumer products. Although many studies have assessed their levels in house dust, only a few used dust samples captured by filters of building heating, ventilation, and air conditioning (HVAC) systems. HVAC filters collect particles from large volumes of air over a long period of time (potentially known) and thus provide a spatially and temporally integrated concentration. This study measured concentrations of phthalates and organophosphates in HVAC filter dust and settled floor dust collected from low-income homes in Texas, United States, in both the summer and winter seasons. The most frequently detected compounds were benzyl butyl phthalate (BBzP), di-(2-ethylhexyl) phthalate (DEHP), di-n-octyl phthalate (DnOP), tris (1-chloro-2-propyl) phosphate (TCIPP), triphenyl phosphate (TPHP), and tris (1,3-dichloroisopropyl) phosphate (TDCIPP). The median level of TCIPP in settled dust was 3- to 180-times higher than levels reported in other studies of residential homes. Significantly higher concentrations were observed in HVAC filter dust as compared to settled dust for most of the frequently detected compounds in both seasons, except for several phthalates in the winter. SVOC concentrations in settled dust in winter were generally higher than in summer, while different seasonality patterns were found for HVAC filter dust. Settled dust samples from homes with vinyl flooring contained significantly higher levels of BBzP and DEHP as compared to homes with other types of floor material. The concentration of DEHP and TDCIPP in settled dust also significantly associated with the presence of carpet in homes. Cleaning activities to remove dust from furniture actually increased the levels of certain compounds in HVAC filter dust, while frequent vacuuming of carpet helped to decrease the concentrations of some compounds in settled dust. Additionally, the size and age of a given house also correlated with the levels of some pollutants in dust. A statistically significant association between DEHP concentration in HVAC filter dust in summer and the severity of asthma in children was observed. These results suggest that HVAC filter dust represents a useful sampling medium to monitor indoor SVOC concentrations with high sensitivity; in contrast, when using settled dust, in addition to consideration of seasonal influences, it is critical to know the sampling location because the type and level of SVOCs may be related to local materials used there.

Temporal trends in serum polybrominated diphenyl ether concentrations in the Australian population, 2002-2013

In Australia, systematic biomonitoring of persistent organic pollutants (POPs) in pooled serum samples stratified by age and sex has occurred every two years between 2002/03 and 2012/13. Multiple regression modeling on log10-transformed serum pool concentrations of BDEs 47, 99, 100 and 153 and on the sum of these (Σ₄PBDE) was conducted to examine trends by sex and time since baseline, stratified by age group. Temporal trends were age- and congener-specific, with the largest changes per year of observation in the 0-4 year old group, with β (SE) = -0.098 (0.013) for log₁₀BDE47; -0.119 (0.012) for log₁₀BDE99; -0.084 (0.014) for log₁₀BDE100, and -0.053 (0.013) for log₁₀BDE153, all p < 0.001. Adults over age 16 showed much smaller decreasing temporal trends for BDE47 and BDE99, no significant changes in BDE100, and, for the oldest age groups, slight increases in BDE153. As a result, Σ₄PBDE concentrations were stable over the entire time period in adults older than 16. Concentrations of each BDE in pools from females aged 31-60 were significantly lower compared to males. Relative proportions of BDE47 declined, while BDE153 accounted for a greater share of Σ₄PBDE over time. Whereas previously we saw a large elevation in the youngest age groups compared to older children and adults, this is no longer the case. This may be due to a decline in infant and toddler exposures in the indoor environment as use of PBDEs in consumer products has been phased out, suggesting temporal changes in the relative sources of exposure for young children in Australia.

Portable X-ray fluorescence for the detection of POP-BFRs in waste plastics

The purpose of this study was to establish the efficacy of portable X-ray fluorescence (XRF) instrumentation as a screening tool for a variety of end of life plastics which may contain excess amounts of brominated flame retardants (BFRs), in compliance with European Union (EU) and United Nations Environment Programme (UNEP) legislative limits (low POP concentration limits - LPCLs). 555 samples of waste plastics were collected from eight waste and recycling sites in Ireland, including waste electrical and electronic equipment (WEEE), textiles, polyurethane foams (PUFs), and expanded polystyrene foams. Samples were screened for bromine content, in situ using a Niton™ XL3T GOLDD XRF analyser, the results of which were statistically compared to mass spectrometry (MS)-based measurements of polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCDD) and tetrabromobisphenol-A (TBBP-A) concentrations in the same samples. Regression between XRF and MS for WEEE samples shows that, despite an overall favourable trend, large deviations occur for a cluster of samples indicative of other bromine-based compounds in some samples; even compensating for false-positives due to background interference from electronic components, XRF tends to over-estimate MS-determined BFR concentrations in the 100 to 10,000 mg kg^-1 range. Substantial deviations were additionally found between results for PUFs, textiles and polystyrene samples, with the XRF over-estimating BFR concentrations by a factor of up to 1.9; this is likely due to matrix effects influencing XRF measurements. However, expanded (EPS) and extruded polystyrene (XPS) yielded much more reliable estimations of BFR-content due to a dominance of HBCDD in these materials. XRF proved much more reliable as a "pass/fail" screening tool for LPCL compliance (including a prospective LPCL on Deca-BDE based on REACH). Using a conservative threshold of BFR content exceeding legislative limits (710 mg kg^-1 bromine attributed to Penta-BDE), XRF mistakenly identifies only 6 % of samples (34/555) as exceeding legislative limits.

Black plastics: Linear and circular economies, hazardous additives and marine pollution

Black products constitute about 15% of the domestic plastic waste stream, of which the majority is single-use packaging and trays for food. This material is not, however, readily recycled owing to the low sensitivity of black pigments to near infrared radiation used in conventional plastic sorting facilities. Accordingly, there is mounting evidence that the demand for black plastics in consumer products is partly met by sourcing material from the plastic housings of end-of-life waste electronic and electrical equipment (WEEE). Inefficiently sorted WEEE plastic has the potential to introduce restricted and hazardous substances into the recyclate, including brominated flame retardants (BFRs), Sb, a flame retardant synergist, and the heavy metals, Cd, Cr, Hg and Pb. The current paper examines the life cycles of single-use black food packaging and black plastic WEEE in the context of current international regulations and directives and best practices for sorting, disposal and recycling. The discussion is supported by published and unpublished measurements of restricted substances (including Br as a proxy for BFRs) in food packaging, EEE plastic goods and non-EEE plastic products. Specifically, measurements confirm the linear economy of plastic food packaging and demonstrate a complex quasi-circular economy for WEEE plastic that results in significant and widespread contamination of black consumer goods ranging from thermos cups and cutlery to tool handles and grips, and from toys and games to spectacle frames and jewellery. The environmental impacts and human exposure routes arising from WEEE plastic recycling and contamination of consumer goods are described, including those associated with marine pollution. Regarding the latter, a compilation of elemental data on black plastic litter collected from beaches of southwest England reveals a similar chemical signature to that of contaminated consumer goods and blended plastic WEEE recyclate, exemplifying the pervasiveness of the problem.

Assessment of dermal exposure to halogenated flame retardants: Comparison using direct measurements from hand wipes with an indirect estimation from settled dust concentrations

There are few studies estimating dermal exposure to halogenated flame retardants in adults. To fill this gap, sixty-one hand wipe samples were collected from a Norwegian adult cohort using gauze pads immersed in isopropanol. BDE-47, BDE-209, bis(2‑ethyl‑hexyl)‑3,4,5,6‑tetrabromophthalate (BEH-TEBP) and decabromodiphenylethane (DBDPE) were the most frequently detected chemicals. The highest median mass in hand wipes was that of sumEHFR (570 ng), followed by sumHBCDD (180 ng) and sumPBDE (2.9 ng). The high EHFR level was mainly driven by tetrabromobisphenol A (TBBPA) which accounted for 77% of the total mass. Positive and significant correlations were observed between FR levels in hand wipes and settled dust (0.26 < r < 0.56, p < 0.05), as well as between FR levels in hand wipes and the number of electronic consumer products at home (0.27 < r < 0.40, p < 0.05). Significant bivariate associations with number of laptops/tablets and phones/mobiles were further confirmed by multivariate linear regression analyses. Dermal exposure was estimated using the levels measured in handwipes. The estimated median dermal exposure was 2600, 840 and 6.2 pg/kg bw/d for sumEHFR, sumHBCDD and sumPBDE, respectively. Further, we compared these results with the dermal exposure as estimated indirectly by utilizing previously reported FR levels in settled dust collected from the residences of the same studied cohort. With the indirect approach, higher dermal exposures to sumPBDE but lower exposures to sumEHFR and sumHBCDD were observed compared to the direct dermal exposure estimated via hand wipes. Comparable exposure estimates between hand wipes and the indirect method were obtained for α‑, β‑tetrabromoethylcyclohexane (DBE-DBCH), DBDPE, BDE-28, -35, -49, -99, -153, 154, and -183. For other individual HFRs, the exposure estimates obtained from the two approaches were significantly different (Mann-Whitney U test, p < 0.05). Both methods gave similar dermal exposure estimates for many individual FRs. However, it is important to be aware of the value and limitations of each method when using them to estimate human exposure.

Determination of legacy and novel brominated flame retardants in dust from end of life office equipment and furniture from Pretoria, South Africa

Indoor dust is known to be a source of human exposure to brominated flame retardants (BFRs) and these consists of the legacy polybrominated diphenyl ethers (PBDEs), total hexabromocyclododecane (T-HBCDD) and the "Novel or alternate" Brominated flame retardants (NBFRs). In this study, x-ray fluorescence (XRF) analyser was employed to measure elemental bromine contents in office furniture and electronics as the first indication of the possible presence of BFRs. To investigate the possible BFRs present, a total of 21 dust samples were collected from surfaces of electronic equipment and office furniture and were analysed using gas chromatography-mass spectrometry (GC-MS). The concentrations of ∑₇ BDE- congeners ranged from 50 to 3346ngng^-1. Of the ∑₇ BDE congeners analysed, BDE-209, -183 and -99 were the most dominant congeners. The concentrations observed ranged from <LOD - 1758, <LOD - 401 and <LOD-543ngg^-1, for BDE-209, -183 and -99, respectively. T-HBCDD and 2-ethyl-1-hexyl-2.3.4.5-tetrabromobenzoate (EH-TBB) were detected in 57 and 67% of the total dust samples analysed with concentrations ranging from <LOD - 673 and <LOD - 385ngg^-1, respectively. However, Bis (2-ethylhexyl) tetrabromophthalate (BEH-TEBP) was only detected in 24% of the 21 samples exhibiting a concentration range of <LOD - 63ngg^-1. The detection frequency of 1,2 Bis (2.4.6-tribromophenoxy) ethane (BTBPE) was 81% with concentrations of <LOD-1402ngg^-1. Alongside the legacy BFRs, NBFRs were the most detected indicating probably increased usage as replacements for the banned commercial PBDEs products namely, penta-, octa-, and deca-BDE mixtures. No correlation was observed between the bromine levels obtained using portable XRF and the BFRs detected using GC-MS (r=0.0073, p=0.076). The observed trend may be attributed to various factors including the sample matrix analysed and the number of BFRs analysed. The observed trend is consistent with those reported from other studies.

Organophosphate and brominated flame retardants in Australian indoor environments: Levels, sources, and preliminary assessment of human exposure

Concentrations of nine organophosphate flame retardants (OPFRs) and eight polybrominated diphenyl ethers (PBDEs) were measured in samples of indoor dust (n = 85) and air (n = 45) from Australian houses, offices, hotels, and transportation (buses, trains, and aircraft). All target compounds were detected in indoor dust and air samples. Median ∑₉OPFRs concentrations were 40 μg/g in dust and 44 ng/m³ in indoor air, while median ∑₈PBDEs concentrations were 2.1 μg/g and 0.049 ng/m³. Concentrations of FRs were higher in rooms that contained carpet, air conditioners, and various electronic items. Estimated daily intakes in adults are 14000 pg/kg body weight/day and 330 pg/kg body weight/day for ∑₉OPFRs and ∑₈PBDEs, respectively. Our results suggest that for the volatile FRs such as tris(2-chloroethyl) phosphate (TCEP) and TCIPP, inhalation is expected to be the more important intake pathway compared to dust ingestion and dermal contact.

Concentrations and Migratabilities of Hazardous Elements in Second-Hand Children's Plastic toys

About 200 second-hand plastic toys sourced in the UK have been analyzed by X-ray fluorescence spectrometry for hazardous elements (As, Ba, Cd, Cr, Hg, Pb, Sb, Se) and Br as a proxy for brominated flame retardants. Each element was detected in >20 toys or components thereof with the exception of As, Hg, and Se, with the frequent occurrence of Br, Cd, and Pb and at maximum concentrations of about 16000, 20000, and 5000 μg g^-1, respectively, of greatest concern from a potential exposure perspective. Migration was evaluated on components of 26 toys under simulated stomach conditions (0.07 M HCl) with subsequent analysis by inductively coupled plasma spectrometry. In eight cases, Cd or Pb exceeded their migration limits as stipulated by the current EU Toy Safety Directive (17 and 23 μg g^-1, respectively), with Cd released from yellow and red Lego bricks exceeding its limit by 1 order of magnitude. Two further cases were potentially noncompliant based on migratable Cr, with one item also containing >250 μg g^-1 migratable Br. While there is no retroactive regulation on second-hand toys, consumers should be aware that old, mouthable, plastic items may present a source of hazardous element exposure to infants.

High levels of medium-chain chlorinated paraffins and polybrominated diphenyl ethers on the inside of several household baking oven doors

Fat obtained by wipe tests on the inner surface of 21 baking ovens from Stuttgart (Germany) were analyzed for halogenated flame retardants (HFRs), namely polybrominated diphenyl ethers (PBDEs), decabromodiphenyl ethane (DBDPE), dechlorane plus (DP), short- and medium-chain chlorinated paraffins (SCCPs, MCCPs), as well as polychlorinated biphenyls (PCBs). In ~50% of the samples chlorinated paraffins (CPs) were present in the mg/g fat range, i.e. three to four orders of magnitude higher concentrated than the sum of all other target compounds. In contrast the remaining ~50% of the samples were free of CPs, while the other HFRs were comparable in CP-positive and CP-negative samples. The exceptionally high concentrations and exclusive presence of CPs in half of the samples produced strong evidence that these compounds were released from the baking oven itself. This hypothesis was supported by detection of MCCPs at even higher concentrations in the inner components of one dismantled baking oven. The release of substantial amounts of HFRs from the oven casing during its use may contribute to human exposure to these compounds, especially MCCPs and SCCPs.

Brominated flame retardants in black plastic kitchen utensils: Concentrations and human exposure implications

Concerns exist that restricted brominated flame retardants (BFRs) present in waste polymers may have, as a result of recycling, inadvertently contaminated items not required to meet flame retardancy regulations (e.g. plastic kitchen utensils). To investigate the extent to which kitchen utensils are contaminated with BFRs and the potential for resultant human exposure, we collected 96 plastic kitchen utensils and screened for Br content using a hand-held X-ray fluorescence (XRF) spectrometer. Only 3 out of 27 utensils purchased after 2011 contained detectable concentrations of Br (≥3μg/g). In contrast, Br was detected in 31 out of the 69 utensils purchased before 2011. Eighteen utensils with Br content higher than 100μg/g, and 12 new utensils were selected for GC-MS analysis of BFRs. BFRs targeted were polybrominated diphenyl ethers (PBDEs) BDE-28, 47, 99, 100, 153, 154, 183 and 209, and novel BFRs (NBFRs) pentabromoethylbenzene (PBEB), 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (EH-TBB), 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), bis(2-ethylhexyl)-3,4,5,6-tetrabromo-phthalate (BEH-TEBP) and decabromodiphenyl ethane (DBDPE). The ability of XRF to act as a surrogate metric of BFR concentration was indicated by a significant (Spearman coefficient=0.493; p=0.006) positive relationship between Br and ΣBFR concentration. Measurements of ΣBFRs were always exceeded by those of Br. This may be due partly to the presence of BFRs not targeted in our study and also to reduced extraction efficiency of BFRs from utensils. Of our target BFRs, BDE-209 was the most abundant one in most samples, but an extremely high concentration (1000μg/g) of BTBPE was found in one utensil. Simulated cooking experiments were conducted to investigate BFR transfer from selected utensils (n=10) to hot cooking oil, with considerable transfer (20% on average) observed. Estimated median exposure via cooking with BFR contaminated utensils was 60ng/day for total BFRs. In contrast, estimated exposure via dermal contact with BFR-containing kitchen utensils was minimal.

WEEE plastic sorting for bromine essential to enforce EU regulation

The plastics of waste of electric and electronic equipment (WEEE) are improved for fire safety by flame retardants, and particularly brominated flame retardants (BFR). As waste, the management of these plastic fractions must comply with the update of the regulation of waste hazard classification (2014, 2017), the publication of a technical standard on management of WEEE (2015), and a restriction of use for decabromodiphenylether in the product regulation (2017). Data of bromine (n=4283) and BFR concentrations (n=98) in plastics from electric and electronic equipment (EEE), and from WEEE processing facilities before and after sorting for bromine in four sites in France have been studied for chemical composition and for regulatory classification. The WEEE was analysed by handheld X-ray fluorescence, and the waste was sorted after shredding, by on-line X-ray transmission for total bromine content (< or > 2000 mg/kg) in small household appliances (SHA), cathode ray tubes (CRT) and flat screens plastics. In equipment (n=347), 15% of the equipment items have no bromine, while 46% have at least one part with bromine, and 39% have all parts brominated. The bromine concentration in plastics is very heterogeneous, found in high concentrations in large household appliance (LHA) plastics, and also found in unexpected product categories, as observed by other authors. Clearly, an unwanted global loop of brominated substances occurs via the international recycling of plastic scrap. In waste (n=65), polybromobiphenyls, polybromodiphenylethers (PBDE), tetrabromobisphenol A (TBBPA) and hexabromocyclododecane were analysed. The most concentrated BFRs are decaBDE (3000 mg/kg) and TBBPA (8000 mg/kg). The bromine concentration of regulated brominated substances was identified in 2014 and 2015 to be up to 86% of total bromine in "old" waste (SHA, CRT), 30-50% in "younger" waste (Flat screens), and a mean of only 8% in recent products (2009-2013). Regulated substances are a minority of all the brominated substances and the only practical way to sort is to measure total bromine on-line. The sorting reduces the mean bromine concentration in the "Low Br" fraction in all sites, and reduces the decaBDE concentration to levels below the restricted use limit. After sorting, the concentration in the "High Br" fractions exceeds all present or future regulatory limits. In conclusion, sorting of small household appliances, cathode ray tubes and flat screen plastics is necessary to avoid uncontrolled dispersion of regulated substances in recycled raw material. Other categories (large household appliances, electric and electronic tools, lighting equipment) should also be considered, since their total bromine content (unweighted mean concentration) is high for some of these products. A European campaign consisting of 7 countries and 35 sites will begin in 2017, directed by WEEE Forum, the European association speaking for thirty-one not-for-profit e-waste producer responsibility organisations, to assess the mean bromine content of plastics from large household appliances after shredding.

Flame retardants on the surface of phones and personal computers

Mobile phones and personal computers (PCs) are essential products that are frequently contacted in daily life. Thus, phones and computers containing flame retardants (FRs) may play vital roles in human exposure to FRs. We measured several FRs, including polybrominated diphenyl ethers (PBDEs), 1,2-bis(2,4,6-tribromophenoxy) ethane (BTBPE), decabromodiphenyl ethane (DBDPE), tetrabromobisphenol (TBBPA), and phosphate flame retardants (PFRs), on the surfaces of phones and PCs (laptop keyboards and mice). Triphenyl phosphate (TPHP, 228pg/cm²) and tris(chloroisopropyl) phosphate (TCIPP, 43pg/cm²) were the most abundant chemicals on the surfaces of phones, while TPHP (65pg/cm²), TCIPP (48pg/cm²), and DBDPE (22pg/cm²) were dominant on the surfaces of PCs. The usage time and time after the production of the electronics were not significantly correlated with the FR concentrations, except for that of BDE 209. The concentrations of FRs differed on the surfaces of different brands of electronics. Dermal contact with the surface of electronics may contribute to human exposure to FRs, which should be of concern.

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.

Brominated and phosphate flame retardants (FRs) in indoor dust from different microenvironments: Implications for human exposure via dust ingestion and dermal contact

Indoor dust has been widely used to monitor flame retardants (FRs) in indoor environment, but most studies only focused on floor dust. In the present study, FRs were examined in indoor dust from different locations. Dust from air conditioner (AC) filters, beddings, floor, and windows in bedrooms, and dust from AC filters, printer table surface, computer table surface, floor, and windows in offices were collected, respectively. Polybrominated diphenyl ether congener 209 (BDE 209) and decabromodiphenyl ethane (DBDPE) were the most abundant brominated flame retardants (BFRs), and tris(chloroisopropyl) phosphate (TCIPP), tris(1,3-dichloroisopropyl) phosphate (TDCIPP), and triphenyl phosphate (TPHP) were the most abundant phosphate flame retardants (PFRs). In bedrooms, the AC filter dust had the highest median levels of BDE 209 (536 ng/g) and DBDPE (2720 ng/g), while bed dust had the highest median levels of ΣPFRs (2750 ng/g) among dust samples. In offices, printer table dust had higher median levels of BDE 209 (1330 ng/g), DBDPE (8470 ng/g), and ΣPFRs (11,000 ng/g) than those in other dust samples. The high dust ingestion values of BDE 209, DBDPE, and individual PFR were 0.28, 1.20, and <0.01-0.32 ng/kg bw/day and 7.37, 31.2, and <0.01-4.54 ng/kg bw/day for BDE 209, DBDPE, and individual PFR for adults and toddlers, respectively. The high dermal exposure values of individual PFR during sleeping were <0.01-0.23 and <0.01-0.36 ng/kg bw/day for adults and toddlers, respectively. More human exposure pathways other than dust ingestion should be considered, such as the dermal contact with beddings and furniture.

Screening for halogenated flame retardants in European consumer products, building materials and wastes

To fulfill national and international fire safety standards, flame retardants (FRs) are being added to a wide range of consumer products and building materials consisting of flammable materials like plastic, wood and textiles. While the FR composition of some products and materials has been identified in recent years, the limited global coverage of the data and the large diversity in consumer products necessitates more information for an overall picture of the FR composition in common products/materials. To address this issue, 137 individual samples of various consumer products, building materials and wastes were collected. To identify and characterize potential sources of FRs in indoor environment, all samples were analyzed for content of polybrominated diphenyl ethers (PBDEs), hexabromocyclododecanes (HBCDDs) and novel flame retardants (NFRs). The most frequently detected were HBCDDs (85%), with the highest median concentration of Σ₄HBCDDs of 300 mg kg^-1 in polystyrenes. The highest median concentration of Σ₁₀PBDEs was found in recycled plastic materials, reaching 4 mg kg^-1. The lowest concentrations were observed for NFRs, where the median of Σ₁₂NFRs reached 0.4 mg kg^-1 in the group of electrical & electronic equipment wastes. This suggests that for consumer products and building materials that are currently in-use, legacy compounds still contribute to the overall burden of FRs. Additionally, contrasting patterns of FR composition in recycled and virgin plastics, revealed using principle component analysis (PCA), suggest that legacy flame retardants are reentering the market through recycled products, perpetuating the potential for emissions to indoor environments and thus for human exposure.

Seasonality and indoor/outdoor relationships of flame retardants and PCBs in residential air

This study is a systematic assessment of different houses and apartments, their ages and renovation status, indoors and outdoors, and in summer vs. winter, with a goal of bringing some insight into the major sources of semivolatile organic compounds (SVOCs) and their variability. Indoor and outdoor air concentrations of polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and novel flame retardants (NFRs) were determined at 17-20 homes in Czech Republic in winter and summer. Indoor concentrations were consistently higher than outdoor concentrations for all compounds; indoor/outdoor ratios ranged from 2-20, with larger differences for the current use NFRs than for legacy PCBs. Seasonal trends differed according to the use status of the compounds: the PCBs had higher summer concentrations both indoors and outdoors, suggesting volatilization as a source of PCBs to air. PBDEs had no seasonal trends indoors, but higher summer concentrations outdoors. Several NFRs (TBX, PBT, PBEB) had higher indoor concentrations in winter relative to summer. The seasonal trends in the flame retardants suggest differences in air exchange rates due to lower building ventilation in winter could be driving the concentration differences. Weak relationships were found with building age for PCBs, with higher concentrations indoors in buildings built before 1984, and with the number of electronics for PBDEs, with higher concentrations in rooms with three or more electronic items. Indoor environments are the primary contributor to human inhalation exposure to these SVOCs, due to the high percentage of time spent indoors (>90%) combined with the higher indoors levels for all the studied compounds. Exposure via the indoor environment contributed ∼96% of the total chronic daily intake via inhalation in summer and ∼98% in winter.

From Clothing to Laundry Water: Investigating the Fate of Phthalates, Brominated Flame Retardants, and Organophosphate Esters

The accumulation of phthalate esters, brominated flame retardants (BFRs) and organophosphate esters (OPEs) by clothing from indoor air and transfer via laundering to outdoors were investigated. Over 30 days cotton and polyester fabrics accumulated 3475 and 1950 ng/dm(2) ∑5phthalates, 65 and 78 ng/dm(2) ∑10BFRs, and 1200 and 310 ng/dm(2) ∑8OPEs, respectively. Planar surface area concentrations of OPEs and low molecular weight phthalates were significantly greater in cotton than polyester and similar for BFRs and high molecular weight phthalates. This difference was significantly and inversely correlated with KOW, suggesting greater sorption of polar compounds to polar cotton. Chemical release from cotton and polyester to laundry water was >80% of aliphatic OPEs (log KOW < 4), < 50% of OPEs with an aromatic structure, 50-100% of low molecular weight phthalates (log KOW 4-6), and < detection-35% of higher molecular weight phthalates (log KOW > 8) and BFRs (log KOW > 6). These results support the hypothesis that clothing acts an efficient conveyer of soluble semivolatile organic compounds (SVOCs) from indoors to outdoors through accumulation from air and then release during laundering. Clothes drying could as well contribute to the release of chemicals emitted by electric dryers. The results also have implications for dermal exposure.

Improving the accuracy of hand-held X-ray fluorescence spectrometers as a tool for monitoring brominated flame retardants in waste polymers

An optimised method for Br quantification as a metric of brominated flame retardant (BFR) concentrations present in Waste Electrical and Electronic Equipment (WEEE) polymers is proposed as an alternative to the sophisticated, yet time consuming GC-MS methods currently preferred. A hand-held X-ray fluorescence (XRF) spectrometer was validated with Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS). Customized standard materials of specific BFRs in a styrenic polymer were used to perform an external calibration for hand-held XRF ranging from 0.08 to 12 wt% of Br, and cross-checking with LA-ICP-MS having similar LODs (0.0004 wt% for LA-ICP-MS and 0.0011 wt% for XRF). The "thickness calibration" developed here for hand-held XRF and the resulting correction, was applied to 28 real samples and showed excellent (R(2) = 0.9926) accordance with measurements obtained via LA-ICP-MS. This confirms the validity of hand-held XRF as an accurate technique for the determination of Br in WEEE plastics. This is the first use of solid standards to develop a thickness-corrected quantitative XRF measurement of Br in polymers using LA-ICP-MS for method evaluation. Thermal desorption gas chromatography mass spectrometry (TD-GC-MS) was used to confirm the presence of specific BFRs in WEEE polymer samples. We propose that expressing limit values for BFRs in waste materials in terms of Br rather than BFR concentration (based on a conservative assumption about the BFR present), presents a practical solution to the need for an accurate, yet rapid and inexpensive technique capable of monitoring compliance with limit values in situ.

Environmental occurrence, analysis and human exposure to the flame retardant tetrabromobisphenol-A (TBBP-A)-A review

TBBP-A is a high production volume chemical applied widely as a flame retardant in printed circuit boards. Recent studies have raised concern over potential harmful implications of TBBP-A exposure in human and wildlife, leading to its classification under group 2A "Probably carcinogenic to humans" by the International Agency for Research on Cancer. This article provides a comprehensive review of the available literature on TBBP-A analysis, environmental levels and human exposure. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) has been identified as the method of choice for robust, accurate and sensitive analysis of TBBP-A in different matrices. TBBP-A has been detected in almost all environmental compartments all over the world, rendering it a ubiquitous contaminant. Human exposure studies revealed dust ingestion and diet as the major pathways of TBBP-A exposure in the general population. Toddlers are likely to be more exposed than adults via accidental indoor dust ingestion. Moreover, exposure to TBBP-A may occur prenatally and via breast milk. There are no current restrictions on the production of TBBP-A in the EU or worldwide. However, more research is required to characterise human exposure to TBBP-A in and around production facilities, as well as in e-waste recycling regions.