Electronic Waste Dismantling Research Articles

Polybrominated biphenyl exposure and thyroid function tests in electronic waste dismantling and general population of Chinese adults

This study aimed to determine the concentration of 35 PBB (polybrominated biphenyls) congeners in the human serum of residents from an electronic waste (e-waste) dismantling area compared to a control area in China. Additionally, four thyroid hormones, namely FT3, FT4, TSH, and TRH, were also analyzed. The findings revealed that the total PBB concentrations (sum of the 35 PBB congeners) ranged from 47.1 to 1360 ng/g lipid in the e-waste area and 105–1980 ng/g lipid in the control area. BB-1 and BB-10 were the dominant congeners in both study areas, followed by BB-209. Compared to the e-waste dismantling area, the control area samples had a significantly higher concentration of less-brominated (Br1–3) PBBs, including the concentrations of less-brominated congeners such as BB-1, BB-4, BB-9, and BB-10, which were significantly higher than those in the e-waste dismantling area. Conversely, more-brominated hexabromobiphenyl congeners BB- 153, BB-154 and BB-155 were found in samples from the e-waste dismantling area at significantly higher concentrations than in the control area. E-waste dismantling areas have released historically produced commercial PBB products, but equally not negligible is the exposure of the general population to newly produced PBB congeners. PBB concentrations in the e-waste dismantling area samples decreased with increasing age, while they increased with increasing age in the control area samples. Furthermore, stepwise multiple regression analysis showed a significant association between BB-103 concentrations and thyroid hormone levels. In addition, BB- 103 has the potential to interfere with the binding of T3 and thyroid hormone receptors (TR). Given these findings, the research on human exposure of PBB and the relationships between the PBB and thyroid hormones should be studied further.

Research on the Screening Method of Priority Pollutants with Integrated Environmental Socio-economic Indicators: Example of E-waste Dismantling

While benefiting mankind, electronic information technology has led to the elimination of many electrical and electronic products due to its rapid update and iteration speed. In addition, the normal use in daily life causes the wear and tear of electronic products, resulting in a large amount of electronic waste. With the increase in electronic products, the amount of electronic waste dismantling has also increased yearly. Therefore, it becomes an important to accurately screen the priority control pollutants generated in e-waste process. In view of the current situation of e-waste dismantling pollution and the needs of monitoring and evaluation in China, this study proposed a screening model that combined analysis at levels and systematic clustering methods and performed a comprehensive score of pollutants and cluster analysis on the basis of assigning and scoring the evaluation factors of e-waste dismantling, taking the most potentially dangerous class in the cluster results as the priority control pollutant.

Emission characteristics of (halogenated) polycyclic aromatic hydrocarbons during printed circuit board combustion and estimated emission intensity of a typical e-waste dismantling site in South China

The pollution of polycyclic aromatic hydrocarbons (PAHs) and halogenated PAHs (Cl/Br-PAHs) caused by electronic waste dismantling activities have attracted considerable attention. The present study investigated the emissions and formation of PAHs and Cl/Br-PAHs based on the combustion of printed circuit boards simulating electronic waste dismantling process. The emission factor of ΣPAHs was 648 ± 56 ng/g, which was much lower than that of ΣCl/Br-PAHs (8.80 × 104 ± 9.14 × 103 ng/g). From 25 to 600 °C, the emission rate of ΣPAHs reached a sub-peak of 7.39 ± 1.85 ng/(g•min) at 350 °C, then increased gradually with the fastest rate of 19.9 ± 21.8 ng/(g•min) at 600 °C, whereas that of ΣCl/Br-PAHs was the fastest at 350 °C with a rate of 597 ± 106 ng/(g•min), then decreased gradually. The present study suggested that the formation pathways of PAHs and Cl/Br-PAHs are by de novo synthesis. Low molecular weight PAHs were readily partitioned into gas and particle phases, whereas high molecular weight fused PAHs were only detected in oil phase. However, the proportion of Cl/Br-PAHs in particle and oil phases were different from that of gas phase, whereas similar to that of the total emission. In addition, PAH and Cl/Br-PAH emission factors were used to estimate the emission intensity of pyrometallurgy project in Guiyu Circular Economy Industrial Park, and it was shown that approximately 1.30 kg PAHs and 176 kg Cl/Br-PAHs would be emitted annually. This study revealed that Cl/Br-PAHs would be formed by de novo synthesis, and for the first time provided the emission factors of Cl/Br-PAHs during the heat treatment process of printed circuit board, as well as estimated the contribution of pyrometallurgy, a new electronic waste recovery technology, to environmental Cl/Br-PAH pollution, which provides potential scientific information for governmental decision-making on the control of Cl/Br-PAHs.

Integrated Analysis on Source-exposure Risk of Heavy Metals in Farmland Soil Based on PMF Model: A Case Study in the E-waste Dismantling Area in Zhejiang Province

In order to explore the characteristics and sources of heavy metals in farmland soil and their risks to human health and to provide an important scientific basis for farmland pollution control, 133 surface soils (0-20 cm) were collected from typical agricultural production areas in Zhejiang Province, and the contents of soil Cd, Pb, Cr, Cu, Zn, Ni, As, and Hg were determined. Various methods were applied to evaluate the degree of heavy metal pollution in farmland and its ecological risks in the study area. The method of combining Kriging interpolation and positive definite matrix factor analysis (PMF) was applied to analyze the pollution sources and quantify the contribution of each pollution source. Combined with the health risk assessment model, the risk to human health of each pollution source was evaluated from the perspective of source exposure. The results showed that the average ω(Cd), ω(Pb), ω(Cr), ω(Cu), ω(Zn), ω(Ni), ω(As), and ω(Hg) were 0.76, 65.22, 92.02, 103.92, 198.49, 36.65, 5.97, and 0.20 mg·kg-1, respectively. The average contents of Cd and Cu were higher than the risk screening values of soil contamination of agricultural land, and 85.71% and 96.24% of soil was contaminated by heavy metals. The average contents of Pb, Cr, Zn, and Ni exceeded the soil background values of the Wenhuang Plain in Zhejiang Province, and the As and Hg contents were within the limit values. The potential soil ecological risks were mainly light-moderate, accounting for 90.98%, and both high and higher risk accounted for 4.51%; Cd was the main potential ecological risk element. The main sources of heavy metal pollution in the study area were the sources of the electronic waste dismantling process (26.82%), the mixed sources of coal combustion and traffic emissions (34.50%), mixed sources of natural parent materials and agricultural inputs (25.59%), and e-waste pickling runoff and solid waste leaching sources (13.09%). The health risk of heavy metal exposure to children was significantly greater than that in adults. Mixed sources of natural parent materials and agricultural inputs contributed the most to human health risks, and Cr was the element with the greatest contribution to human health risks.

Depth-dependent patterns of soil microbial community in the E-waste dismantling area

The long-term dismantling of electronic waste (E-waste) has contaminated the soil environment considerably. In spite of this, it is unknown if it affects the depth-resolved microbial communities. In the present research, six soil profiles (dismantling sites and the surrounding farmland) were collected from one of the largest Chinese E-waste disposal centers to identify depth-resolved microbiota and assess how heavy metal contamination affects microbial adaptation. Results suggested that cadmium (0.12-7.22mgkg-1) and copper (18.99-11282.03mgkg-1) were the main pollutants in the test soil profiles, and their concentrations gradually decreased with depth. The surrounding contaminated farmland has a more complex interaction and higher modularity (0.77-0.85) among microbes, indicating a stronger niche differentiation to enhance functional diversity. The proportion of positive interactions between taxa decreased with depth, as high heavy metals contamination in the topsoil results in the co-occurrence of microorganisms with the same ecological niche that collaborated to face environmental stress. Soil physicochemical properties, heavy metals concentration, and soil depth critically affect microbial communities. Microbial community assembly processes in the topsoil were affected by environmental filtering, i.e., by deterministic processes (NST: 13-52%), while were more stochastic (NST: 46-72%) in the subsoil due to the environment of soil becoming more homogeneous as soil depth increased.

Source apportionment of soil heavy metals: A new quantitative framework coupling receptor model and stable isotopic ratios

Tracing the source of heavy metals in soils is crucial for reversing the worrisome situation of heavy metal contamination. In this study, the origins of heavy metal pollution in soil were examined in a primary electronic waste treatment and disposal hub in China, using a synergistic source apportionment framework consisting of the positive matrix factorization (PMF) model and the Bayesian stable-isotope analysis mixing model (MixSIAR). Industrial activity is significant to heavy metal contamination in both industrial park and farmland soils, however, the contribution varied through PMF model (industrial park, 64.2%; farmland, 35.6%). In the industrial park, Pb was identified as the major pollutant in the soils, and the local children suffered from noncarcinogenic risks. Moreover, the contribution of Pb contamination sources were allocated more accurately (electronic waste dismantling, 25.1%; industrial production, 23.7%; vehicle exhaust from leaded gasoline, 9.1%; vehicle exhaust from unleaded gasoline, 20.2%; natural process, 21.9%) using MixSIAR for the first time. The main soil contaminants in surrounding farmland were Cd, Cu, and Zn. The variations in heavy metal pollution sources in soils were found to be associated with local policies and regulations, such as the phasing out of leaded gasoline and the conversion of industrial park from electronic waste demolition switched to production and storage. The identification of the source of heavy metals in soil will support targeted reduction of the associated emissions, which can immediately help alleviating soil contamination and control human health risks.

Activity-based exposure levels and lifetime cancer risk for workers exposed to polychlorinated biphenyls during electronic waste dismantling in Buriram province, Thailand

The activity-based exposure concentrations of airborne polychlorinated biphenyls (PCBs) for electronic waste (e-waste) dismantling workers in Buriram province were examined, and their possible carcinogenic risk was assessed. The average exposure concentration of total PCBs in the particle (PM2.5–10 and PM2.5) and gas phases were 53.51 ± 23.68, 65.41 ± 23.06, and 82.72 ± 78.61 ng/m3, respectively, and were all significantly (p < 0.05) higher for workers exposed during burning wires than those of the dismantling bulky-, small-, and internal e-waste parts. The dominant PCB congeners mainly found during e-waste dismantling were the low-chlorinated group, including PCB-28, -52, −77, −81, −105, −118, and −126. PCB-28 and -77 were observed as predominant co-congeners derived from mechanical dismantling, whereas PCB-52, -118, and −126 were the main species emitted from burning activities. The workers exposed to PCBs from burning wires were estimated to have the highest lifetime cancer risk of 1.64E-05, about 2.5- to 3.3-fold higher than those who dismantled bulky-, small- and internal e-waste parts. Consequently, workers should be recommended to wear high-efficiency respiratory protection masks to avoid direct exposure to PCBs and to reduce their possible carcinogenic risk.

Quantification and characterization of recovered materials in the cycle of the informal household electronic waste dismantling in Buriram province, Thailand: A challenge towards sustainable management and circular economy.

The numerous amount of electronic waste (e-waste) has not been managed effectively resulting informal dismantling sites are being expanded in Thailand. The government attempts to improve the efficiency of an integrated e-waste management system, but baseline data of e-waste stream in informal sectors are insufficient. This research aimed to investigate the inflow and outflow of the materials throughout the informal e-waste dismantling processes at the well-known second-largest community in Buriram province during 2017-2018. To describe the quantities of dismantled materials, a material flow analysis was performed. The overall amount of e-waste taken to the community was estimated to be in the range of 1593-12,943 tonnes year-1. Valuable materials could be recovered at more than 90% (by mass) from fans, refrigerators, washing machines, microwaves and air conditioners. The amount of e-waste residue that the local administrative organization had to handle was up to 1144 tonnes year-1. The quantitative data retrieved from this study could provide a satisfactory equation for estimating the amount of separated valuable and non-valuable materials. Recyclable materials from dismantling have an economic incentive, e-waste dismantlers in a small and large household group that can earn approximately 798 and 1262 USD month-1 income, respectively. The notable e-waste characterization and quantification of recovered materials would be useful for improving the potential circular flow of e-waste in Thailand.

Spatial Distribution Characteristics and Risk Assessment of Cadmium Pollution in Soil-crops system of an E-waste Dismantling Area

With the rapid development of electronic technology, soil heavy metal contamination caused by electronic waste dismantling activities has attracted the attention of many researchers. To investigate the contamination status and spatial distribution of Cd in soil-crop systems around an e-waste dismantling area, 171 pairs of soil and crop samples were collected for analysis. The concentrations of cadmium in root vegetable soil, leaf vegetable soil, solanaceous vegetable soil, and orchard soil were (1.292±0.647), (1.010±0.201), (0.921±0.125), and (0.861±0.135) mg·kg-1, respectively. The average values of cadmium in these four soil types were 10.0, 7.8, 7.1, and 6.3 times the background values of soil Cd in Zhejiang Province, respectively, and 4.31, 3.4, 3.07, and 2.72 times the risk screening values for soil contamination of agricultural land, clearly indicating cadmium accumulation in the soil. However, only a small percentage of crops contained cadmium levels that exceeded food safety limits. Moreover, different types of crops showed different capacities for cadmium enrichment and can be ranked accordingly: leaf vegetables > root vegetables > solanaceous vegetables > fruits. The single factor pollution index and the potential ecological risk assessment revealed severe Cd contamination in the study area, with a high potential ecological risk. Cadmium exposure posed a higher health risk for children than for adults. However, the single heavy metal cadmium pollution index does not indicate a threat to local residents at this time. Moran's I index and kriging interpolation results revealed that Cd has significant spatial autocorrelation, with high values mainly concentrating around the e-waste dismantling area, indicating a significant correlation with e-waste dismantling activities.

Treatment of waste gas from electronic dismantling workshop

At present, due to China’s electronic waste treatment technology is not mature enough. In the market, a large number of electronic wastes into the household dismantling workshop and through simple, inefficient, extensive way to recycle. After the extraction of valuable resources, the remaining toxic and harmful substances are discharged at will, resulting in a high level of toxic and harmful pollutants in the air of the region. The deposition of harmful and harmful pollutants in the air also further leads to the deterioration of the local soil, water and other ecological environment, threatening the health and survival of local residents. The paper takes the exhaust gas from electronic waste dismantling process based on family workshop of Guiyu town as the experimental object. Water absorption and activated carbon adsorption were applied to treat exhaust gas. And the ferreite precipitation was used to treat the recirculated wastewater after spray system. The experiment results indicate that the lead cadmium, tin and its compounds and benzene series could be removed above 95% after water absorption and active carbon adsorption. The lead, cadmium and copper in recirculated wastewater respectively could be removed 96.69%, 79.76% and 90.82% after ferrite precipitation process.

Previously identified and unidentified polybrominated biphenyl congeners in serum from people living in an electronic waste dismantling area in China

The effects of polybrominated biphenyls (PBBs) on human health have previously attracted much attention, but recent studies of PBBs have been focused on BB-153 and a few other congeners. PBB concentrations in serum samples from residents of an area containing an electronic waste dismantling site were determined in this study. The total PBB concentrations (i.e., the sums of the concentrations of the 35 PBB congeners) were 229–1360 ng/g lipid. The BB-153 concentrations were markedly higher in the samples from people living in the electronic waste dismantling area than in samples from people living in a nearby control area. BB-153 was found in all of the samples from the study exposure area but the concentrations were relatively low (0.07–4.70 ng/g lipid). High BB-1 concentrations were found for the first time in serum from people living in both the electronic waste dismantling and control areas. The BB-1 concentrations were 211–1280 ng/g lipid. The retention times of the 35 PBB standards and PCBs (polychlorinated biphenyls) with similar structures were used to predict the retention times of unidentified PBB congeners to allow the PBB distributions in the serum samples to be identified. A total of 26 previously unidentified PBB congeners were identified in the human serum samples. BB-5, BB-35, BB-79, and BB-109 were found in >50% of the samples. The PBB patterns in the serum samples were different from the patterns previously found in serum after a PBB contamination incident in 1973, so the health risks currently posed by PBBs are worth studying.

Potential use of Impatiens balsamina L. for bioremediation of lead and polychlorinated biphenyl contaminated soils

AbstractIn recent years, due to the improper dismantling of electronic waste (e‐waste) in China, high levels of lead (Pb) and polychlorinated biphenyls (PCBs) have been released into the environment, which posed potential health risks to residents, especially to children. A pot‐culture experiment was carried out to evaluate the phytoremediation potential of PCBs and Pb co‐contaminated soil by the use of Impatiens balsamina L. The results indicated that PCBs and Pb had negative effect on plant growth, while the presence of PCBs partially alleviated Pb toxicity to I. balsamina. The existence of PCBs showed nonsignificant effects on Pb uptake by I. balsamina. However, the presence of PCBs influenced the distribution of Pb among plant tissues. The order of Pb accumulation in tissues was roots &gt; stems &gt; leaves, indicating the plant may be suitable for the phytostabilization of Pb in soil. The degradation rates of PCB 18 (25–68%) and PCB 28 (14–61%) in the planted soil was significantly higher than that in the unplanted soil, which confirmed the vegetation is beneficial for the biodegradation of PCBs in soils. Plant–microbial consortia in the rhizosphere make a predominant contribution to PCBs dissipation in the co‐contaminated soil. Significant differences in microbial taxonomic composition between the contaminated soils and a blank control were observed. I. balsamina could have the potential for remediating PCBs and lead co‐contaminated soils, even though further field studies are still required.

Health risk assessment of airborne Cd, Cu, Ni and Pb for electronic waste dismantling workers in Buriram Province, Thailand

This study aimed to assess the risk levels of electronic waste dismantling workers in Buriram Province from exposure to cadmium (Cd), copper (Cu), nickel (Ni) and lead (Pb) via inhalation. The study area was Dang-Yai subdistrict, Baan Mai Chaiyapot district, Buriram province, Thailand. The sampling of particulate matter of less than 10 μm (PM10) was performed from 8 a.m. to 5 p.m. each day between 14th and 18th December 2015 inclusively. The PM10 was collected on a glass fiber filter using a nylon cyclone connected to a personal air pump with an air flow rate of 1.7 L/min. The samples were extracted by a microwave digester, and the metals were analyzed by inductively coupled plasma optical emission spectrometry. The average exposure concentrations of the workers to Cd, Cu, Ni and Pb were 0.0073 ± 0.0084, 0.2083 ± 0.6362, 0.3499 ± 0.3738 and 0.1297 ± 0.1746 μg/m3, respectively. The hazard quotients (HQs) of the non-carcinogenic effect of Cd, Cu and Ni, had 95% confidence intervals (CIs) of 0.067–0.167, 0.012–0.018 and 0.333–0.913, respectively. All HQs were less than 1, which indicated that there was no concern of increased non-carcinogenic health risks. The lifetime cancer risk (70 y) of the workers estimated for a 30-y exposure period showed 95% CIs of 7.55–18.6 × 10−5, 1.69–4.66 × 10−5 and 3.26–9.66 × 10−7 for Cd, Ni and Pb, respectively. Thus, the possible cancer risk levels from exposure to Cd and Ni for these workers were higher than the acceptable criterion of 10−6, which indicated that the workers have the potential to get cancer from electronic waste dismantling, due to cadmium and nickel exposure.

Thermal degradation and pollutant emission from waste printed circuit boards mounted with electronic components

Waste printed circuit boards mounted with electronic components (WPCB-ECs) are generated from electronic waste dismantling and recycling process. Air-borne pollutants, including particulate matter (PM) and volatile organic compounds (VOCs), can be released during thermal treatment of WPCB-CEs. In this study, organic substances from WPCB-ECs were pyrolyzed by both thermo-gravimetric analysis (TGA) and in a quartz tube furnace. We discovered that board resin and solder coating were degraded in a one-stage process, whereas capacitor scarfskin and wire jacket had two degradation stages. Debromination of brominated flame retardants occurred, and HBr and phenol were the main products during TGA processing of board resin. Dehydrochlorination occurred, and HCl, benzene and toluene were detected during the pyrolysis of capacitor scarfskin. Benzene formation was found only in the first degradation stage (272–372 °C), while toluene was formed both in the two degradation stages. PM with bimodal mass size distributions at diameters of 0.45–0.5 and 4–5 μm were emitted during heating WPCB-ECs. The PM number concentrations were highest in the size ranges of 0.3–0.35 μm and 1.6–2 μm. The research produced new data on pollutant emissions during thermal treatment of WPCB-ECs, and information on strategies to prevent toxic exposures that compromise the health of recyclers.

Human exposure to phthalate esters associated with e-waste dismantling: Exposure levels, sources, and risk assessment

Phthalate esters (PAEs) can be released into the environment during the dismantling of electronic waste (e-waste), but urinary levels of PAE metabolites (mPAEs) in humans living in e-waste sites have not been documented. In this study, 11 mPAEs were determined in urine samples collected from participants living in e-waste dismantling sites and a reference area in Southern China. The total urinary concentrations of the 11 mPAEs (∑mPAEs) in the e-waste sites (range: 11.1 ng/mL to 3380 ng/mL) were dominated by mono-(2-isobutyl) phthalate and mono-n-butyl phthalate. Participants living in the e-waste sites had significantly higher (p < 0.05) urinary concentrations of ∑mPAEs (and 5 individual mPAEs) than those in the reference area. Hence, e-waste dismantling activities contributed to human exposure to PAEs. The exposure doses of di-n-butyl phthalate, di(2-ethylhexyl)phthalate, di-iso-butyl phthalate, dimethyl phthalate, and diethyl phthalate were 3.41, 3.04, 1.37, 0.25, and 0.20 μg/kg bw/day, respectively. Furthermore, the health risk assessment in terms of hazard quotient and hazard index showed that approximately 22% of the participants living in the e-waste sites had HI values exceeding 1; importantly, 68% of them were non-adults (i.e., 0–18 years old). In the e-waste sites, 8 of the 11 mPAEs in urine samples had significantly positively associations (r = 0.185–0.358, p < 0.05) with the urinary concentration of 8-hydroxy-2′-deoxyguanosine, a marker of DNA oxidative stress. Therefore, people living in e-waste dismantling areas may have a potential health risk caused by PAE exposure. To the best of our knowledge, this study is the first to measure urinary mPAE levels in people living in e-waste dismantling areas.

Distribution Characteristics and Health Risk Assessment of Heavy Metals in a Soil-Rice System in an E-waste Dismantling Area

This study selected Guiyu Town, Guangdong Province as the research area, the content of 15 kinds of metals (As, Be, Cd, Co, Cr, Cu, Hg, Li, Mn, Ni, Sb, Sn, Pb, V, and Zn) in the soil was determined, and the content of heavy metals (As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn in the rice of this research area was identified. Multivariate statistical analysis and a human health risk assessment model were used to investigate the distribution characteristics and health risk of heavy metals in a soil-rice system. The results showed that Hg, Sb, and Sn in the surface soil surrounding the electronic waste dismantling area have obvious accumulation effect. The average content of Cd and Hg exceeds the Ⅱ standard limit of the "Environmental Quality Standard for Soil" (GB 156182-1995), and that Guiyu Town is more seriously polluted than Chendian Town and Simapu Town. The multivariate statistical analysis showed that Cu, Sb, Ni, Zn, Sn, Pb, and Hg originated from the surrounding electronic waste dismantling activities, Cd and Be originated from other man-made sources of pollution, and V, Li, Cr, Co, As, and Mn originated from natural sources. Heavy metal evaluation concentration in the soil-rice system by heavy metal migration accumulated in rice are in compliance with national food hygiene standards, and the enrichment ability is Cd > Zn > Cu > Ni > As > Cr > Hg > Pb. Soil heavy metal health risk assessment results showed that children are more susceptible to heavy metal pollution, and handling-oral ingestion is the main way of soil exposure risk. The non-carcinogenic risk and carcinogenic risk of heavy metals in the soil of each town are acceptable. The health risk in Guiyu Town through ingestion of rice is mainly from the elements that include As, Cr, Cu, and Ni.

Toxic effects of polybrominated diphenyl ethers (BDE 47 and 99) and localization of BDE-99-induced cyp1a mRNA in zebrafish larvae.

Polybrominated diphenyl ethers (PBDEs) were once widely used as flame retardants in furniture and electronic products, and contamination persists in developing countries due to the dismantling of electronic waste. Our previous study confirmed that 2,2',4,4',5-pentabromodiphenyl ether (BDE-99) induced cytochrome P450 1A (Cyp1a) via aryl hydrocarbon receptor (Ahr)-mediated signaling in the zebrafish liver cell line (ZFL) in vitro. In this study, the toxicities of BDE-47 and BDE-99 at environmentally relevant concentrations (50 and 500nM) were evaluated in newly hatched zebrafish (Danio rerio) larvae in vivo. A time-course study (8, 24, 48, and 96h) was performed. BDE-99 was observed to cause yolk sac edema and pericardial edema after 72h of exposure. Real-time polymerase chain reaction assay and whole-mount in situ hybridization assay confirmed cyp1a induction by BDE-99 in the liver and intestine. Continuous down-regulation of trβ by as much as 2.1-fold after 96h and transient down-regulation of ttr by 7.1-fold after 24h indicated the interference of BDE-99 in the thyroid hormone system. cyp1a induction was also observed in BDE-47-treated larvae, but cellular localization of cyp1a was not confirmed by whole-mount in situ hybridization. The induction of four cyp1 genes (cyp1a, cyp1b1, cyp1c1 and cyp1c2) by both BDE congeners warrants further study to understand the in vivo metabolism of BDE-47 and BDE-99 and the dioxin-like toxicity potencies of the OH-/MeO-PBDEs. The data obtained in this study will aid the characterization of molecular disorders caused by PBDEs in fish and help to delineate better models for toxicity assessment of environmental pollutants in ecological systems and in other vertebrates such as humans.

The assessment of source attribution of soil pollution in a typical e-waste recycling town and its surrounding regions using the combined organic and inorganic dataset.

Guiyu is a well-known electronic waste dismantling and recycling town in south China. Concentrations and distribution of the 21 mineral elements and 16 polycyclic aromatic hydrocarbons (PAHs) collected there were evaluated. Principal component analyses (PCA) applied to the data matrix of PAHs in the soil extracted three major factors explaining 85.7% of the total variability identified as traffic emission, coal combustion, and an unidentified source. By using metallic or metalloid element concentrations as variables, five principal components (PCs) were identified and accounted for 70.4% of the information included in the initial data matrix, which can be denoted as e-waste dismantling-related contamination, two different geological origins, anthropogenic influenced source, and marine aerosols. Combining the 21 metallic and metalloid element datasets with the 16 PAH concentrations can narrow down the coarse source and decrease the unidentified contribution to soil in the present study and therefore effectively assists the source identification process.

Draft Genome Sequence of Bacillus sp. GZT, a 2,4,6-Tribromophenol-Degrading Strain Isolated from the River Sludge of an Electronic Waste-Dismantling Region.

Here, we report the draft genome sequence of Bacillus sp. strain GZT, a 2,4,6-tribromophenol (TBP)-degrading bacterium previously isolated from an electronic waste-dismantling region. The draft genome sequence is 5.18 Mb and has a G+C content of 35.1%. This is the first genome report of a brominated flame retardant-degrading strain.

VOCs elimination and health risk reduction in e-waste dismantling workshop using integrated techniques of electrostatic precipitation with advanced oxidation technologies

Volatile organic compounds (VOCs) emitted during the electronic waste dismantling process (EWDP) were treated at a pilot scale, using integrated electrostatic precipitation (EP)-advanced oxidation technologies (AOTs, subsequent photocatalysis (PC) and ozonation). Although no obvious alteration was seen in VOC concentration and composition, EP technology removed 47.2% of total suspended particles, greatly reducing the negative effect of particles on subsequent AOTs. After the AOT treatment, average removal efficiencies of 95.7%, 95.4%, 87.4%, and 97.5% were achieved for aromatic hydrocarbons, aliphatic hydrocarbons, halogenated hydrocarbons, as well as nitrogen- and oxygen-containing compounds, respectively, over 60-day treatment period. Furthermore, high elimination capacities were also seen using hybrid technique of PC with ozonation; this was due to the PC unit’s high loading rates and excellent pre-treatment abilities, and the ozonation unit’s high elimination capacity. In addition, the non-cancer and cancer risks, as well as the occupational exposure cancer risk, for workers exposed to emitted VOCs in workshop were reduced dramatically after the integrated technique treatment. Results demonstrated that the integrated technique led to highly efficient and stable VOC removal from EWDP emissions at a pilot scale. This study points to an efficient approach for atmospheric purification and improving human health in e-waste recycling regions.