Source apportionment and risk assessment for polycyclic aromatic hydrocarbons in soils at a typical coking plant.

Polycyclic aromatic hydrocarbons (PAHs) are widely present in the environment. The coking industry is an important industrial source of PAHs. Coke production in China accounts for 67.44% of total global coke production. Tangshan, a coastal city on the Bohai Rim, contains the largest cluster of coking plants in China. Extremely high PAH emissions in Tangshan may cause long-distance cross-border pollution problems. In this study, the concentrations and sources of 16 priority PAHs in soil at a coking plant in Tangshan were determined and the risks posed by the PAHs were assessed. The PAH concentrations were generally higher in surface soil than subsurface soil, particularly near the coke oven, crude benzol, and coal blending areas. The dibenz[a,h]anthracene (DBA) concentrations were higher than the risk screening value (1500 ngg-1) but lower than the control value (15,000 ngg-1) for type II land defined in Chinese standard (GB36600-2018). The main sources of PAHs were coal combustion, the coke oven, and traffic. The PAH concentrations were higher in the ammonium sulfate, boiler room, coal blending, and coke oven areas than in the other areas. Toxic equivalent concentrations were calculated to assess the toxic and carcinogenic risks posed by PAHs. The toxic equivalent concentrations were relatively high in the boiler, crude benzol, and coal blending areas, where the toxic equivalent concentrations for the sums of seven highly carcinogenic PAHs contributed 95% of the toxic equivalent concentrations for the sums of the 16 PAHs that were analyzed. The carcinogenic risks posed to humans were therefore assessed using the concentrations of the seven highly carcinogenic PAHs. Dermal contact was found to be an important exposure pathway leading to carcinogenic risks. The carcinogenic risk posed by DBA was > 1 × 10-6 but < 5 × 10-6, indicating that DBA concentrations at the study site monitored closely.

Are perfluoroalkyl substances in water and fish from drinking water source the major pathways towards human health risk?

Due to potential adverse effects and bioaccumulation in biota and humans, perfluoroalkyl substances (PFASs) have raised wide attention in recent years. Ingestion is a vital pathway for PFASs to transmit to humans especially through water and fish. In present study, PFASs in water and fish from the drinking water source of Beijing in China were investigated. Three layers of water were collected in order to find the connection between concentrations of PFASs and depth of water, which showed no prominent correlation. PFASs in water from Miyun Reservoir with concentrations of 5.30-8.50 ng/L, were relatively lower compared with other reports on raw drinking water. Perfluorobutanoic acid (PFBA) and perfluorooctanoic acid (PFOA) were the dominant PFASs. In addition, six species of fish (including Cyprinus carpio, Carassius auratus, Erythroculter dabryi, Pseudohemiculter dispar, Hypophthalmichthys molitrix and Siniperca chuatsi) were analyzed, with concentrations of PFASs ranging from 1.70 to 14.32 ng/g wet weight (w.w.). Due to relatively stronger bioaccumulation potential, long chain perfluorinated carboxylates (PFCAs) and perfluorinated sulfonates (PFSAs) were detected with higher concentrations, especially perfluoroundecanoic acid (PFUdA) and perfluorodecanoic acid (PFDA). The estimated daily intake (EDI) of PFASs through drinking water and fish consumption were 0.20-0.34 and 3.44-12.61 ng/kg bw/day based on Exposure Factors Handbook of Chinese Population, respectively. In addition, the EDI of high-priority concern PFASs via pork, chicken and dust were also calculated, with value of 0.015-0.043, 0.003-0.013 and 0.074-0.390 ng/kg bw/day, respectively. The total EDI of PFOS and PFOA via diverse pathways were less than suggested tolerable daily intake (PFOS, 150 ng/kg bw/day; PFOA, 1500 ng/kg bw/day), indicating that the detected levels would not cause severe health effects on Beijing residents.

Urban-rural gradients of polycyclic aromatic hydrocarbons in soils at a regional scale: Quantification and prediction.

The quantitative study of urban-rural gradients for persistent organic pollutants (POPs) is extremely important to understand the behavior of POPs as well as for ecological risk assessment and management. In this study, a practical urban-rural gradient model (URGM) was developed using atmospheric point source diffusion combined with a fugacity approach to test potential mathematical relationships among urban and rural soils. The mean value of polycyclic aromatic hydrocarbons (PAHs) for urban soils (0-2-km sites) was 570.80 ng/g, and was approximately 3.5 times higher than rural soils (30-50 km sites). Significant linear correlations were found between the amounts of PAHs in the surface soil and the city population and between the soil concentration and artificial surface area. Urban-rural PAH concentrations were simulated by the URGM and calibrated by city population and land-cover data, with average relative errors of 12.84%. The results showed that the URGM was suitable for simulating urban-rural PAH concentrations at a regional scale. The combustion of fossil fuels, biomass, and coal was the main source of soil PAHs in the study area, and the characteristic ratios of PAHs indicated a transition trend from pyrogenic to petrogenic sources along the urban-rural transects. This study thus provides a combined method for quantifying urban-rural gradients of PAHs and can thereby promote quantitative research on coupling among land cover, socio-economic data, and POP concentrations.

Climate change induced eutrophication of cold-water lake in an ecologically fragile nature reserve.

Aquatic ecosystem sustainability around the globe is facing crucial challenges because of increasing anthropogenic and natural disturbances. In this study, the Tianchi Lake, a typical cold-water lake and a UNESCO/MAB (Man and Biosphere) nature reserve located in high latitude and elevation with the relatively low intensity of human activity was chosen as a system to examine the linkages between climate change and eutrophication. As a part of the UNESCO Bogda Man and Biosphere Reserve, Tianchi Lake has been well preserved for prevention from human intervention, but why has it been infected with eutrophication recent years? Our results show that climate change played a significant role in the eutrophication in the Tianchi Lake. Increased temperature, changed precipitation pattern and wind-induced hydrodynamic fluctuations in the summer season were suggested to make a major contribution to the accelerated eutrophication. The results also showed that the local temperature and precipitation changes were closely linked to the large-scale atmospheric circulation, which opens the door for the method to be applied in other regions without local climatic information. This study suggests that there is an urgent need to take into consideration of climate change adaptation into the conservation and management of cold-water lakes globally.

Determination of water environment standards based on water quality criteria in China: Limitations and feasibilities.

There is a need to formulate water environment standards (WESs) from the current water quality criteria (WQC) in China. To this end, we briefly summarize typical mechanisms applied in several countries with longer histories of developing WESs, and three limitations to formulating WESs in China were identified. After analyzing the feasibility factors including economic development, scientific support capability and environmental policies, we realized that China is still not ready for a complete change from its current nation-wide unified WES system to a local-standard-based system. Thus, we proposed a framework for transformation from WQC to WESs in China. The framework consists of three parts, including responsibilities, processes and policies. The responsibilities include research authorization, development of guidelines, and collection of information, at both national and local levels; the processes include four steps and an impact factor system to establish water quality standards; and the policies include seven specific proposals.

Urban and rural transport of semivolatile organic compounds at regional scale: A multimedia model approach.

Urban areas are generally regarded as major sources of some semivolatile organic compounds and other persistent organic pollutants (POPs) to the surrounding regions. Huge differences in contaminant emissions between urban and rural areas directly affect their fate in environmental media. Little is known about POPs behavior between urban and rural areas at a regional scale. A spatially resolved Berkeley-Trent-Urban-Rural Fate Model (BETR-UR) was designed by coupling land cover information to simulate the transport of POPs between urban and rural areas, and the Bohai Rim was used as a case study to estimate Polycyclic Aromatic Hydrocarbon (PAH) fate. The processes of contaminant fate including emission, inter-compartmental transfer, advection and degradation in urban and rural areas were simulated in the model. Simulated PAH concentrations in environmental media of urban and rural areas were very close to measured values. The model accuracy was highly improved, with the average absolute relative error for PAH concentrations reduced from 37% to 3% compared with unimproved model results. PAH concentrations in urban soil and air were considerably higher than those in rural areas. Sensitivity analysis showed temperature was the most influential parameter for Phen rather than for Bap, whose fate was more influenced by emission rate, compartment dimension, transport velocity and chemical persistence. Uncertainty analysis indicated modeled results in urban media had higher uncertainty than those in rural areas due to larger variations of emissions in urban areas. The differences in urban and rural areas provided us with valuable guidance on policy setting for urban-rural POP control.

Distribution and bioaccumulation of lead in the coastal watersheds of the Northern Bohai and Yellow Seas in China.

In this study, the concentration of lead ([Pb]) in the surface water, sediments, soils and muscles of carp and crab in the upstream and downstream coastal watersheds along the Northern Bohai and Yellow Seas (NBYS) in China was investigated and the risks of Pb were evaluated. The mean [Pb] in the downstream water (2.62 µg/L) and sediments [24.5 mg/kg, dry mass (dm)] was greater than the Chinese seawater quality standard for class I (1 µg/L) and the regional background soil concentration (11.5 mg Pb/kg, dm), respectively. Approximately 37 % of the soils, mainly from the upstream regions, had [Pb] greater than the regional background concentration of 21.4 mg/kg, dm. The sites with relatively large [Pb] in the water, sediments and soils were located in the coastal watersheds of Tangshan and Huludao. The large enrichment factors in the sediments (2.41) and soils (2.22) suggested that human activities influenced the soils and sediments in this region more than in the other regions. Relatively large [Pb] was found in the crabs that were obtained from the upstream reaches of the Shuanglong and Daliao Rivers and the downstream reaches of the Luanhe and Liugu Rivers. Most of the crabs from the upstream regions contained greater [Pb] than the permissible limit for human consumption [0.3 mg/kg, wet mass (wm)]. The risk indices of the water, carp and crabs for humans were 0.002, 0.01 and 0.006, respectively. Based on the bioaccumulation factors, biota-sediment accumulation factors (BSAFs) and human risk indices, it was concluded that the human risks associated with crab were lower than those of carp despite the greater accumulation of Pb by the crabs from the water and sediments. Finally, the [Pb] in the sediments was significantly correlated with the [Pb] in the soils, which indicated that the same sources of Pb were responsible for the [Pb] in the sediments and soils in the coastal watersheds of the NBYS in China.

Perfluoroalkyl substances in Daling River adjacent to fluorine industrial parks: implication from industrial emission.

The pollution level and source of perfluoroalkyl substances (PFASs) in mainstream and tributary of Daling River in northeast China were investigated in present study. Concentrations of PFASs in surface water and sediment ranged from 4.6 to 3,410 ng/L and from 0.08 to 2.6 ng/g dry weight, respectively. The lowest levels of PFASs were found in vicinity of a drinking water source located in upstream of Daling River. Xihe tributary, which is adjacent to two local fluorine industrial parks, contained the highest level of PFASs. Short-chain PFASs, including perfluorobutanoic acid and perfluorobutane sulfonate, were of higher levels due to their emerging as alternative products for perfluorooctane sulfonate. High level of perfluorooctanoic acid was also found in Daling River. Based on these results, it can be concluded that the relatively severe pollutions of Xihe tributary were caused by long-term development of the two local fluorine industry parks.

Associations between serum concentrations of perfluoroalkyl acids and serum lipid levels in a Chinese population.

Perfluoroalkyl acids (PFAAs) have been used in a variety of products for many years and have been detected worldwide in human serum. Previous studies have suggested the potential effects of PFAAs on serum lipids. To investigate the associations between serum concentrations of PFAAs and serum lipid levels, 133 participants were randomly selected from the people coming for health check-up in Yuanyang Red Cross Hospital of Henan, China. Linear regression analysis revealed that perfluoro-octanoic acid (PFOA), perfluorononanoic acid (PFNA), and perfluorodecanoic acid (PFDA), with a median concentration of 1.43, 0.37, and 0.19 ng/mL, respectively, were positively associated with total cholesterol (TC). Those in the highest quartile of PFOA exposure had ln-TC levels 0.24 mmol/L higher than those in the lowest quartile. For PFNA and PFDA, effect estimates were 0.25 and 0.16 mmol/L, respectively. A positive association between high-density lipoprotein cholesterol (HDLC) and PFDA was found, and there was a 0.18 mmol/L increase of HDLC for the top PFDA quartile compared with the lowest quartile. PFOA and PFNA were positively associated with low-density lipoprotein cholesterol (LDLC). Ln-LDLC levels of people in both top PFOA and PFNA quartiles were 0.33 mmol/L higher than those in the lowest quartiles. Logistic regression analysis indicated that increased PFOA and PFOS quartiles were positively associated with an increased risk of abnormal TC and LDLC when controlling for no confounding factors.

Benzene homologues in environmental matrixes from a pesticide chemical region in China: Occurrence, health risk and management.

The contamination status and health risks of benzene, toluene, ethylbenzene and xylene (BTEX) in air, soil, dust and groundwater were evaluated in a pesticide chemical region located in Hebei province, China. The concentrations of BTEX in air ranged from 7.80 to 238ug/m(3) and those in soil and dust ranged from lower than limit of detection (LOD) to 32,360ng/g dw, and those in groundwater varied from 2.68 to 98.6ug/L. Generally, the levels of BTEX in multimedia matrixes were all below the standards established in China. Health risk assessment was performed based on the monitoring data via inhalation, dermal contact and ingestion pathways and hazard quotient (HQ) was calculated to be on the order of 10(-7), below 10(-6), and Hazard index (HI) levels of BTEX were lower than 1.0. However, both HQ and HI ascended with an increase in work experience/exposure. Integrated risk management was proposed to eliminate BTEX pollution and to protect occupational health of workers in those industries.

Perfluoroalkyl substances and organochlorine pesticides in sediments from Huaihe watershed in China.

Twelve perfluoroalkyl substances (PFASs) and nine organochlorine pesticides (OCPs) were quantified in surface sediments from the Huaihe River, China, along which there are intensive industrial and agricultural activities. Concentrations of PFASs ranged from 0.06 to 0.46ng/g dry weight (dw), and concentrations of OCPs ranged from 1.48 to 32.65ng/gdw. Compared with other areas in China, concentrations of PFASs were lesser than the national mean value, while concentrations of OCPs were moderate. Concentrations of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) ranged from n.d. (not detected) to 0.03 and n.d. to 0.10ng/gdw, respectively. Among the three groups of OCPs, mean concentrations of hexachlorocyclohexane and its isomers (HCHs), dichlorodiphenyltrichloroethane and its metabolites (DDTs) and hexachlorobenzene (HCB) were 5.62±4.35, 2.43±3.12 and 1.55±4.17ng/gdw, respectively. Concentrations of HCHs and DDTs decreased from upstream to downstream along the mainstream of the Huaihe River. When compared to sediment quality guidelines (SQGs), concentrations of HCHs, DDTs and HCB would pose adverse biological effects. In general, contamination by PFASs in the upstream of the Huaihe River was more severe than that in the downstream, which was mainly caused by interception from dams, locks and industrial emissions. And OCPs from tributaries, especially the Yinghe River and Wohe River, were higher than those from Huaihe mainstream, and primarily came from historical inputs.

Factors influencing polychlorinated dibenzo-p-dioxin and polychlorinated dibenzofuran (PCDD/F) emissions and control in major industrial sectors: case evidence from Shandong Province, China.

Analyzing determinants that influence polychlorinated dibenzo-p-dioxin and polychlorinated dibenzofuran (PCDD/F) emissions is helpful for decision-makers to find effective and efficient ways to mitigate PCDD/F emissions. The PCDD/F emissions and the contributions of the scale effect, structure effect and technology effect to emissions from eight main industrial sectors in 2006, 2008 and 2010 in Shandong Province, were calculated in this article. Total PCDD/F emissions in Shandong increased by 52.8% in 2008 (614.1g I-TEQ) and 49.7% in 2010 (601.8 g I-TEQ) based on 2006 (401.9 g I-TEQ). According to the decomposition method, the largest influencing factor on PCDD/F emission changes was the composition effect (contributed 43.4% in 2008 and 120.6% in 2010 based on 2006), which was also an emission-increasing factor. In this case, the present industrial restructuring policy should be adjusted to control the proportion of production capacities with high emission factors, such as iron ore sintering and steel making and the secondary non-ferrous metal sector. The scale effect increased the emissions in 2008 (contributed 21.9%) and decreased the emissions in 2010 (contributed -28.0%). However, as a source control measure, the excess capacity control policy indeed had a significant role in emission reduction. The main reason for the technology effect (contributed 34.7% in 2008 and 7.4% in 2010 based on 2006) having an emission-increasing role was the weakness in implementing policies for restricting industries with outdated facilities. Some specific suggestions were proposed on PCDD/F reduction for local administrators at the end.

Can PFAS threaten the health of fish consumers? A comprehensive analysis linking fish consumption behaviour and health risk.

Despite being phased out for decades, per- and polyfluoroalkyl substances (PFAS) are still widely detected in the environment and accumulated in many aquaculture organisms for human consumption. Thus, there is growing concern about whether fish consumption can cause PFAS-associated health impacts on humans since fish is a vital protein source for global populations. Here, we assess the potential driving factors of fish consumption by analysing the aquaculture, demographic and socio-economic data across 31 provinces/municipalities in China, followed by estimating the health risk of PFAS via fish consumption. We found that per capita fish consumption was primarily driven by fish production and total area for freshwater aquaculture, while urbanization rate and median age of consumers were also important. The health risk of PFAS was low (hazard quotient <1) in most provinces, while urban consumers were more prone to PFAS than rural consumers across all provinces. Since PFAS have been phased out worldwide, their health risk to humans through fish consumption would be lower than previously thought. To reduce PFAS intake for the high-risk populations, we recommend that fish should be well cooked before consumption, preferably using water-based cooking methods, and that alternative protein sources should be consumed more as the substitute for fish.

Spatial distribution, mass flux, and ecological risk of antibiotics in Taiwan and Luzon Straits: A case in the West Pacific Region.

Emerging pollutants are hazardous to the ecological environment and human health, and these issues have attracted increasing attention from scholars. In the current study, the Taiwan Strait is long and narrow, highly influenced by terrestrial domains, and frequently disturbed by human activities. Conversely, the Luzon Strait is an open sea far from the shore, and the impact of human activities on it is minimal. The description of antibiotics in two different types of seas revealed that contaminants were most commonly detected in both straits. In particular, the coasts of the Minjiang River, Jinjiang River, and Jiulong River were found to be pollution hotspots in the Taiwan Strait. The calculation of risk quotients revealed that antibiotics were more sensitive to algae. Furthermore, estimation of the risk quotients of the mixtures found that antibiotics in the environment do not pose a high risk to aquatic organisms at different trophic levels.

Meta-analysis identifying gut microbial biomarkers of Qinghai-Tibet Plateau populations and the functionality of microbiota-derived butyrate in high-altitude adaptation.

The extreme environmental conditions of a plateau seriously threaten human health. The relationship between gut microbiota and human health at high altitudes has been extensively investigated. However, no universal gut microbiota biomarkers have been identified in the plateau population, limiting research into gut microbiota and high-altitude adaptation. 668 16s rRNA samples were analyzed using meta-analysis to reduce batch effects and uncover microbiota biomarkers in the plateau population. Furthermore, the robustness of these biomarkers was validated. Mendelian randomization (MR) results indicated that Tibetan gut microbiota may mediate a reduced erythropoietic response. Functional analysis and qPCR revealed that butyrate may be a functional metabolite in high-altitude adaptation. A high-altitude rat model showed that butyrate reduced intestinal damage caused by high altitudes. According to cell experiments, butyrate may downregulate hypoxia-inducible factor-1α (HIF-1α) expression and blunt cellular responses to hypoxic stress. Our research found universally applicable biomarkers and investigated their potential roles in promoting human health at high altitudes.

Optimizing entropy weight model to accurately predict variation of pharmaceuticals and personal care products in the estuaries and coasts of the South China.

Pharmaceuticals and personal care products (PPCPs) have raised increasing concern worldwide due to their continuous release and potential hazards to the ecosystem and human health. This study optimized the entropy weight model (EW-WRSR) that combines entropy weight with multi-criteria decision analysis to investigate pollution patterns of PPCPs in the coasts and estuaries. The results revealed that occurrences of PPCPs from the 1940s to the present were consistent with using PPCPs, different types of human activities, and local urban development. This helped better understand the history of PPCP contamination and evaluate the uncertainty of EW-WRSR. The model predicted hotspots of PPCPs that were consistent with the actual situation, indicating that PPCPs mainly enter the nearshore ecosystem by the form of sewage discharge and residual aquaculture. This study can provide method that identifying highly contaminated regions on a global scale.

Microplastics and arsenic speciation in edible bivalves from the coast of China: Distribution, bioavailability, and human health risk.

Bivalves, such as oysters and mussels, are exposed to environmental pollutants, like microplastics (MPs) and arsenic (As). This study investigated co-existence and interaction of MPs and As (total As and As species) in two bivalve species from the Chinese coastline. Smaller MPs (20-100 µm) averaged 30.98 items/g, while larger MPs (100-500 µm) averaged 2.98 items/g. Oysters contained more MPs (57.97 items/g) in comparison to mussels (11.10 items/g). In Contrast, mussels had a higher As concentrations (8.36-23.65 mg/kg) than oysters (4.97-11.02 mg/kg). The size and composition of MPs influenced As uptake and speciation in bivalves, with inorganic arsenic (iAs) and methylated arsenic (MMA and DMA) correlating with larger-sized MPs. Polyethylene (PE) may interact with the formation of arsenobetaine (AsB) in oyster. This study provides valuable insights into the interaction of MPs and As in marine ecosystems and highlights their implications for food safety.

Exploring optical descriptors for rapid estimation of coastal sediment organic carbon and nearby land-use classifications via machine learning models.

This study utilizes ultraviolet and fluorescence spectroscopic indices of dissolved organic matter (DOM) from sediments, combined with machine learning (ML) models, to develop an optimized predictive model for estimating sediment total organic carbon (TOC) and identifying adjacent land-use types in coastal sediments from the Yellow and Bohai Seas. Our results indicate that ML models surpass traditional regression techniques in estimating TOC and classifying land-use types. Penalized Least Squares Regression (PLR) and Cubist models show exceptional TOC estimation capabilities, with PLR exhibiting the lowest training error and Cubist achieving a correlation coefficient 0.79. In land-use classification, Support Vector Machines achieved 85.6 % accuracy in training and 92.2 % in testing. Maximum fluorescence intensity and ultraviolet absorbance at 254 nm were crucial factors influencing TOC variations in coastal sediments. This study underscores the efficacy of ML models utilizing DOM optical indices for near real-time estimation of marine sediment TOC and land-use classification.

Silicon photocathode functionalized with osmium complex catalyst for selective catalytic conversion of CO2 to methane.

Solar-driven CO2 reduction to yield high-value chemicals presents an appealing avenue for combating climate change, yet achieving selective production of specific products remains a significant challenge. We showcase two osmium complexes, przpOs, and trzpOs, as CO2 reduction catalysts for selective CO2-to-methane conversion. Kinetically, the przpOs and trzpOs exhibit high CO2 reduction catalytic rate constants of 0.544 and 6.41 s-1, respectively. Under AM1.5 G irradiation, the optimal Si/TiO2/trzpOs have CH4 as the main product and >90% Faradaic efficiency, reaching -14.11 mA cm-2 photocurrent density at 0.0 VRHE. Density functional theory calculations reveal that the N atoms on the bipyrazole and triazole ligands effectively stabilize the CO2-adduct intermediates, which tend to be further hydrogenated to produce CH4, leading to their ultrahigh CO2-to-CH4 selectivity. These results are comparable to cutting-edge Si-based photocathodes for CO2 reduction, revealing a vast research potential in employing molecular catalysts for the photoelectrochemical conversion of CO2 to methane.

Polybrominated diphenyl ethers (PBDEs) in China: policies and recommendations for sound management of plastics from electronic wastes.

Polybrominated diphenyl ethers (PBDEs), used as flame retardants (BFRs), are incorporated in plastics of most electronic equipment. Among BFR mixtures, deca-BDE is the most widely used commercial additive in the polymer industry and the use of deca-BDE is currently not subject to any restrictions in China. However, debate over environmental and health risks associated with deca-BDE still remains. Regulatory agencies in developed countries have adopted and/or established environmentally sound strategies for the management of potential threat posed by PBDEs to the environment and human health. No regulations or management policies for PBDEs currently exist in China at either central or provincial government levels. Large amounts of plastics containing PBDEs are still in use and must be disposed of after their lifetimes, creating outdoor reservoirs for the future dispersal of PBDEs into the environment. Concerted action is needed not only to regulate the production and use of PBDEs but also to find ways to effectively manage waste electrical and electronic products that contain PBDEs. This article is the first to investigate the policy issues and current problems related to the use of PBDEs in China. In addition, we estimate the mass flows of PBDEs contained in Waste Electrical and Electronic Equipment (WEEE) in China. We suggest alternatives to PBDEs and sound management of plastics used in electrical and electronic equipment (EEE) that contain PBDEs.