Chlorinated paraffins (CPs), including short-chain CPs (SCCPs) and medium-chain CPs (MCCPs), are hazardous chemical additives widely applied as plasticizers and flame retardants in polymers, mainly ...in polyvinyl chloride (PVC). In 2017, SCCPs were listed under the Stockholm Convention on Persistent Organic Pollutants (POPs). MCCPs were proposed for listing as POPs in 2021. SCCPs are also restricted under the Basel Convention, with two tentative low POP content (LPC) limits (100 and 10,000 mg kg−1) for SCCPs in waste. As a signatory Party of both conventions, Japan must ensure their implementation and manage SCCP wastes in environmentally sound ways. Therefore, we aimed to assess the occurrence of SCCPs and MCCPs in PVC consumer goods (n = 87) available in the Japanese market. CPs were detected in 48% of the samples. Regarding positive samples, children's products and toys (1.3–120,000 mg kg−1) were more impacted by SCCPs whereas electrical and electronic cables (1.2–59,000 mg kg−1) and house interior products (3.5–550 mg kg−1) were more impacted by MCCPs. Fourteen and four samples exceeded the LPC limit of 100 and 10,000 mg kg−1 for SCCPs, respectively. Most products were impacted by CP contents (<1 % w/w) considerably below those reported as intentional CP uses in PVC. However, 11 samples with total CP contents ranging from 1.3% to 15 % (w/w) might have been impacted by intentional CP use as secondary plasticizer in PVC. Most of the impacted consumer goods available in the Japanese market were manufactured overseas, highlighting that only restricting POPs nationally is not enough for thorough implementation of the Basel and Stockholm Conventions. Therefore, imported PVC consumer goods, PVC waste and PVC recycling streams need to be monitored as relevant potential sources of SCCPs worldwide, even where the national industry strictly follows the restriction of such chemicals.
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•48 % of the PVC-based consumer goods had detectable contents of SCCPs or MCCPs.•Children's products were the most impacted due to SCCP contents up to 12 % (w/w).•SCCP contents in children's products failed the Stockholm Convention restriction.•MCCPs were dominant in cable sheaths and house interior products.•LPC limits proposed by the Basel Convention for SCCPs in waste were exceeded.
Chlorinated Paraffins (CPs) are high volume production chemicals and have been found in various organisms including humans and in environmental samples from remote regions. It is thus of great ...importance to understand the physical-chemical properties of CPs. In this study, gas chromatographic (GC) retention indexes (RIs) of 25 CP congeners were measured on various polar and nonpolar columns to investigate the relationships between the molecular structure and the partition properties. Retention measurements show that analytical standards of individual CPs often contain several stereoisomers. RI values show that chlorination pattern have a large influence on the polarity of CPs. Single Cl substitutions (-CHCl-, -CH
Cl) generally increase polarity of CPs. However, many consecutive -CHCl- units (e.g., 1,2,3,4,5,6-C
Cl
) increase polarity less than expected from the total number of -CHCl- units. Polyparameter linear free energy relationship descriptors show that polarity difference between CP congeners can be explained by the H-bond donating properties of CPs. RI values of CP congeners were predicted using the quantum chemically based prediction tool COSMOthermX. Predicted RI values correlate well with the experimental data (R
, 0.975-0.995), indicating that COSMOthermX can be used to accurately predict the retention of CP congeners on GC columns.
Plastic pollution has become one of the most pressing environmental issues. Recycling is a potential means of reducing plastic pollution in the environment. However, plastic fragments are still ...likely released to the aquatic environment during mechanical recycling processes. Here, we examined the plastic inputs and effluent outputs of three mechanical recycling facilities in Vietnam dealing with electronic, bottle, and household plastic waste, and we found that large quantities of microplastics (plastics <5 mm in length) are generated and released to the aquatic environment during mechanical recycling without proper treatment. Comparisons with literature data for microplastics in wastewater treatment plant effluents and surface water indicated that mechanical recycling of plastic waste is likely a major point source of microplastics pollution. Although there is a mismatch between the size of the microplastics examined in the present study and the predicted no-effect concentration reported, it is still possible that microplastics generated at facilities pose risks to the aquatic environment because there might be many plastic particulates smaller than 315 μm, as suggested by our obtained size distributions. With mechanical recycling likely to increase as we move to a circular plastics economy, greater microplastics emissions can be expected. It is therefore an urgent need to fully understand not only the scale of microplastic generation and release from plastic mechanical recycling but also the environmental risk posed by microplastics in the aquatic environment.
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•Mechanical recycling without wastewater treatment was at least a source of microplastic.•Effluent microplastic concentrations were from 1.1 × 105–2.0 × 108 MP particulates/m3.•Annual microplastic emissions from these facilities were from 0.014 to 5.8 t/year.
Here, we characterized the dioxin-like activities of 42 polychlorinated naphthalenes (PCNs) and 6 technical Halowax formulations by using the DR-CALUX (dioxin-responsive chemically activated ...luciferase expression) assay with rat hepatoma luciferase-expressing H4IIE cells. Of the 42 PCNs examined, 31 showed dioxin-like activities, for which the mass-based REP-EC5TCDD (potency relative to that of 2,3,7,8-tetrachlorodibenzo-p-dioxin based on the 5% effective concentration determined from the dose–response curve for 2,3,7,8-TCDD) ranged from 0.00000012 to 0.0051, indicating that some of the PCNs (e.g., 1,2,3,6,7,8-HxCN and 1,2,3,4,6,7-HxCN) had dioxin-like activities that were equal to or higher than the WHO-TEFs and the mass-based REP-EC5TCDD reported for dioxins such as octachlorodibenzo-p-dioxin, octachlorodibenzofuran, 3,3′,4,4′-tetrachlorobiphenyl (PCB-77), 3,4,4′,5-tetrachlorobiphenyl (PCB-81), and 3,3′,4,4′,5,5′-hexachlorobiphenyl (PCB-169). For PeCNs to OCN with high dioxin-like activities, REPs determined in previous studies were comparable to the REP values obtained in the present study. The TCDD-EQs (2,3,7,8-TCDD equivalents) obtained experimentally for the Halowax formulations decreased in the order HW1051 (37 mg/kg) > HW1014 (30 mg/kg) > HW1013 (5.6 mg/kg) > HW1099 (2.9 mg/kg) > HW1001 (0.60 mg/kg) > HW1031 (<0.10 mg/kg) and were comparable to the theoretical TCDD-EQs calculated by multiplying the concentration and REP of each PCN. In addition, the theoretical TCDD-EQs for PCNs in emission gases produced by thermal processes were below the Japanese emission standard of 0.1–10 ng WHO-toxicity equivalent (TEQ)/m3N, and 3 to 4 orders of magnitude lower than the corresponding WHO-TEQ. Based on a comparison of theoretical and experimental TCDD-EQs, we found that our REP-based approach was suitable for the risk management of industrially produced and unintentionally generated dioxin-like PCNs. This approach will be particularly useful for the risk management of unintentionally generated PCNs in emission gases because the contribution of dioxin-like PCNs to the whole dioxin-like toxicity of emission gases can be elucidated.
•Dioxin-like activities of 42 PCNs and 6 Halowax formulations were evaluated by DR-CALUX assay.•REPs and TCDD-EQs were obtained for 31 PCNs and 5 Halowax formulations.•Theoretical and experimental TCDD-EQs were comparable for the Halowax formulations.•Theoretical TCDD-EQs were lower than the emission standards for dioxins in exhaust gases.•REP-based approaches will be useful for risk management of dioxin-like PCNs.
Wastes containing short-chain chlorinated paraffins (SCCPs) at concentrations above the Basel Convention low persistent organic pollutant content (LPC) values must be destroyed or irreversibly ...transformed in an environmentally-sound manner. Here, we developed a novel liquid chromatography–electrospray ionization-tandem mass spectrometry (LC–ESI-MSMS) method for determining the concentrations of SCCPs in mixed plastic wastes. Major SCCP homologues were identified with good separation and peak width by using a low-hydrophobicity cyano-propyl column and a mobile phase consisting of water and methanol containing ammonium acetate. Precursor ion peaks corresponding to the formation of stable SCCP homologue–adducts were observed, followed by two intense product ion peaks corresponding to separation of the adduct into acetate and the homologue. The formulation of a novel calibration standard with known SCCP homologue percentage composition supported the development of our novel mass spectrometric technique. The results obtained with the LC–ESI-MSMS system were quantitatively and qualitatively comparable with those obtained with a high-resolution mass spectrometry (HRMS) coupled to gas chromatography (GC) system. Homologue concentrations determined by LC–ESI-MSMS were significantly correlated with those determined by GC–HRMS in samples of commercial chlorinated paraffin mixture and mixed plastic waste, respectively. As a complementary technique to the highly accurate, but less versatile GC–HRMS approaches, the SCCP analysis by LC–ESI-MSMS is a practical way to identify mixed plastic wastes containing SCCPs at concentrations higher than the Basel Convention’s LPC value.
•Novel mass spectrometric method to quantify SCCPs in plastic wastes was developed.•Major SCCP homologues were identified with good separation and peak width.•Present data were in good agreement with high-resolution mass spectrometry data.•Plastic wastes containing SCCPs above Basel Convention limits can be identified.
Four commercial oligomeric organophosphorus flame retardants (o-PFRs) were characterized using a refractive index detector and atmospheric pressure photoionization (APPI)-quadrupole time-of-flight ...mass spectrometry (QTOF-MS) compatible with gel permeation chromatography (GPC). Commercial o-PFRs consisted of approximately 90% or more oligomers and several impurities. Triphenyl phosphate (TPHP), tris(dimethylphenyl) phosphate (TDMPP), tris(2-chloroisopropyl) phosphate (TCIPP), and some new impurities were identified as byproducts of some manufacturing process of commercial o-PFRs for the first time. The concentrations of TPHP, TDMPP, and TCIPP were more than 1 weight %, whereas those of new impurities might be approximately 1 weight % by comparison among their abundances acquired through GPC-APPI-QTOF-MS analysis. Based on their vapor pressure and water solubility estimations, the potential environmental emissions of low molecular weight impurities were expected to be higher than those of oligomers. The presence and environmental emissions of low molecular weight impurities might be regarded as risk factors along with commercial o-PFRs.
Three oligomeric organophosphorus flame retardants (o-PFRs), eight monomeric PFRs (m-PFRs), tetrabromobisphenol A (TBBPA), and polybrominated diphenyl ethers (PBDEs) were identified and quantified in ...surface soils and river sediments around the e-waste recycling area in Bui Dau, northern Vietnam. Around the e-waste recycling workshops, 1,3-phenylene bis(diphenyl phosphate) (PBDPP), bisphenol A bis(diphenyl phosphate) (BPA-BDPP), triphenyl phosphate (TPHP), TBBPA, and PBDEs were dominant among the investigated flame retardants (FRs). The respective concentrations of PBDPP, BPA-BDPP, TPHP, TBBPA and the total PBDEs were 6.6–14000ng/g-dry, <2–1500ng/g-dry, 11–3300ng/g-dry, <5–2900ng/g-dry, and 67–9200ng/g-dry in surface soils, and 4.4–78ng/g-dry, <2–20ng/g-dry, 7.3–38ng/g-dry, 6.0–44ng/g-dry and 100–350ng/g-dry in river sediments. Near the open burning site of e-waste, tris(methylphenyl) phosphate (TMPP), (2-ethylhexyl)diphenyl phosphate (EHDPP), TPHP, and the total PBDEs were abundantly with respective concentrations of <2–190ng/g-dry, <2–69ng/g-dry, <3–51ng/g-dry and 1.7–67ng/g-dry in surface soils. Open storage and burning of e-waste have been determined to be important factors contributing to the emissions of FRs. The environmental occurrence of emerging FRs, especially o-PFRs, indicates that the alternation of FRs addition in electronic products is shifting in response to domestic and international regulations of PBDEs. The emissions of alternatives from open storage and burning of e-waste might become greater than those of PBDEs in the following years. The presence and environmental effects of alternatives should be regarded as a risk factor along with e-waste recycling.
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•Open storage and burning of e-waste contributed to emission of FRs.•Types of FRs currently in emission are shifting in response to regulations of PBDEs.•Emerging PFRs were detected in soils and sediments around e-waste recycling area.•Presence of alternatives for PBDEs should be regarded as a risk factor.
We investigated the concentrations of polybrominated diphenyl ethers (PBDEs) and alternative flame retardants (FRs) in environmental samples collected in January 2012, 2013, and 2014 from an ...electronic waste-processing area in northern Vietnam. During the study period, PBDE and alternative FR concentrations in soils around the electronic waste-processing workshops ranged from 37 to 9200 ng g−1 dry weight (dw) and from 35 to 24,000 ng g−1 dw; the concentrations in soils around the open-burning sites ranged from 1.6 to 62 ng g−1 dw and from <4 to 1900 ng g−1 dw; and the concentrations in river sediments around the workshops ranged from 100 to 3800 ng g−1 dw and from 23 to 6800 ng g−1 dw, respectively. Over the course of study period, we observed significant decreases in concentrations of PBDEs and significant increases in concentrations of alternative FRs, particularly Dechlorane Plus isomers and oligomeric organophosphorus FRs (o-PFRs) in both soils and sediments around the workshops. We also report information on concentrations and environmental emissions of o-PFRs and their low-molecular-weight impurities in the same soils and sediments. The detection of o-PFR impurities around the workshops and the open-burning sites highlights an enhanced breakdown of o-PFRs probably due to weathering during open storage and high temperature attained during the burning of electronic wastes.
•PBDE and alternative FR concentrations were determined in the environment for 3 years.•Contamination by PBDEs remains high in the study area.•Concentration of DPs and oligomeric PFRs increased during the study period.•Contaminating constituents might have changed owing to the international regulations.
Untargeted analysis of a composite house dust sample has been performed as part of a collaborative effort to evaluate the progress in the field of suspect and nontarget screening and build an ...extensive database of organic indoor environment contaminants. Twenty-one participants reported results that were curated by the organizers of the collaborative trial. In total, nearly 2350 compounds were identified (18%) or tentatively identified (25% at confidence level 2 and 58% at confidence level 3), making the collaborative trial a success. However, a relatively small share (37%) of all compounds were reported by more than one participant, which shows that there is plenty of room for improvement in the field of suspect and nontarget screening. An even a smaller share (5%) of the total number of compounds were detected using both liquid chromatography–mass spectrometry (LC-MS) and gas chromatography–mass spectrometry (GC-MS). Thus, the two MS techniques are highly complementary. Most of the compounds were detected using LC with electrospray ionization (ESI) MS and comprehensive 2D GC (GC×GC) with atmospheric pressure chemical ionization (APCI) and electron ionization (EI), respectively. Collectively, the three techniques accounted for more than 75% of the reported compounds. Glycols, pharmaceuticals, pesticides, and various biogenic compounds dominated among the compounds reported by LC-MS participants, while hydrocarbons, hydrocarbon derivatives, and chlorinated paraffins and chlorinated biphenyls were primarily reported by GC-MS participants. Plastics additives, flavor and fragrances, and personal care products were reported by both LC-MS and GC-MS participants. It was concluded that the use of multiple analytical techniques was required for a comprehensive characterization of house dust contaminants. Further, several recommendations are given for improved suspect and nontarget screening of house dust and other indoor environment samples, including the use of open-source data processing tools. One of the tools allowed provisional identification of almost 500 compounds that had not been reported by participants.
Information about the co-occurrence of halogenated flame retardants (HFRs) and organophosphate esters (OPEs) in the environment of informal waste processing areas is still limited, especially in ...emerging and developing countries. In this study, OPEs and HFRs including polybrominated diphenyl ethers (PBDEs), novel brominated flame retardants (NBFRs), and chlorinated flame retardants (CFRs) were determined in settled dust from Vietnamese e-waste recycling (WR) and vehicle processing (VP) workshops. Pollutant concentrations decreased in the order: OPEs (median 1500; range 230–410,000 ng/g) ≈ PBDEs (1200; 58–250,000) > NBFRs (140; not detected – 250,000) > CFRs (13; 0.39–2200). HFR and OPE levels in the WR workshops for e-waste and obsolete plastic were significantly higher than in the VP workshops. Decabromodiphenyl ether and decabromodiphenyl ethane are major HFRs, accounting for 60 ± 26% and 25 ± 29% of total HFRs, respectively. Triphenyl phosphate, tris(2-chloroisopropyl) phosphate, and tris(1,3-dichloroisopropyl) phosphate dominated the OPE profiles, accounting for 30 ± 25%, 25 ± 16%, and 24 ± 18% of total OPEs, respectively. The OPE profiles differed between WR and VP dust samples, implying different usage patterns of these substances in polymer materials for electric/electronic appliance and automotive industries. Human health risk related to dust-bound HFRs and OPEs in the study areas was low.
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•Pollutant levels in dust were in the order: PBDEs ≈ OPEs > NBFRs > CFRs.•Informal e-waste recycling activities were potential source of HFRs and OPEs.•BDE-209, DBDPE, and TPHP were major compounds in e-waste recycling sites.•Vehicle workshop dust had low HFR levels and specific OPE profiles.•OPE sources and emission from vehicle processing should be further investigated.
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