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Phthalates are well-known emerging contaminants that harm human health and the environment. Therefore, this review aims to discuss about the occurrence, fate, and phthalates concentration in the various environmental matrices (e.g., aquatic, sediment, soil, and sewage sludge). Hence, it is necessary to treat sources containing phthalates before discharging them to aqueous environment. Various advanced wastewater treatments including adsorption process (e.g., biochar, activated carbon), advanced oxidation processes (e.g., photo-fenton, ozonation, photocatalysis), and biological treatment (membrane bioreactor) have been successfully to address this issue with high removal efficiencies (70–95%). Also, the degradation mechanism was discussed to provide a comprehensive understanding of the phthalate removal for the reader. Additionally, key factors that influenced the phthalates removal efficiency of these technologies were identified and summarized with a view towards pilot-scale and industrial applications.

Refined cobia liver oil is a nutritional supplement (CBLO) that is rich in polyunsaturated fatty acids (PUFAs), such as DHA and EPA, however, PUFAs are prone to oxidation. In this study, the fabrication of chitosan-TPP-encapsulated CBLO nanoparticles (CS@CBLO NPs) was achieved by a two-step method, including emulsification and the ionic gelation of chitosan with sodium tripolyphosphate (TPP). The obtained nanoparticles were inspected by dynamic light scattering (DLS) and showed a positively charged surface with a z-average diameter of between 174 and 456 nm. Thermogravimetric analysis (TGA) results showed the three-stage weight loss trends contributing to the water evaporation, chitosan decomposition, and CBLO decomposition. The loading capacity (LC) and encapsulation efficiency (EE) of the CBLO loading in CS@CBLO NPs were 17.77–33.43% and 25.93–50.27%, respectively. The successful encapsulation of CBLO in CS@CBLO NPs was also confirmed by the Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) techniques. The oxidative stability of CBLO and CS@CBLO NPs was monitored by FTIR. As compared to CBLO, CS@CBLO NPs showed less oxidation with a lower generation of hydroperoxides and secondary oxidation products after four weeks of storage. CS@CBLO NPs are composed of two ingredients that are beneficial for health, chitosan and fish oil in a nano powdered fish oil form, with an excellent oxidative stability that will enhance its usage in the functional food and pharmaceutical industries.

To investigate the spatial distribution and diurnal variation of the chemical composition of PM2.5 pollution in an industrial city of southern Taiwan, 12-h PM2.5 was diurnally continuously collected simultaneously at the Kaoping Air Quality Zone (KAQZ) during one highly PM2.5-polluted episode. Water-soluble ions, metallic elements, carbonaceous contents, dicarboxylic acids, and anhydrosugars were analyzed to characterize the chemical fingerprint of PM2.5. Backward trajectory simulation and chemical mass balance (CMB) receptor modeling were applied to identify the potential sources of PM2.5 and their contributions. It showed that Chaozhou (rural area) accompanying the highest SORs and NORs suffered from the most severe PM2.5 pollution during the episode. Sulfate (SO42−) was probably formed by the atmospheric chemical reaction in the daytime, while NO3− processed at nighttime at the KAQZ. A homogeneous formation of NO3− occurred at Chaozhou. The concentrations of Zn, Pb, Fe, Cu, V, and Al, mainly emitted from anthropogenic sources, increased significantly at the KAQZ. The highest OC, SOC/OC, and DA/OCs at Daliao (industrial area) were attributed to the transformation of primary VOCs to secondary OC via photo-oxidation during the episode. Oxalic acid was mainly produced through photochemical reactions since a high correlation between oxalic acid and Ca2+ was observed at Nanzi (urban area) and Daliao during the episode. During the episode, PM2.5 mostly originated from local primary or secondary aerosol than long-range overseas transport. The dominant source was anthropogenic emissions, accounting for 67.1% and 70.4% of PM2.5 at Nanzi and Daliao, respectively. At Chaozhou, the contribution of anthropogenic emissions was the lowest (42.4%), but secondary aerosols had the highest contribution of 38.3% of PM2.5 among the three areas during the episode.

Box-Behnken design (BBD) was employed to study an optimal treatment method of synthetic lignin wastewater effluent from pulp and paper wastewater treatment plants using iron (III) trimesate (Fe-BTC) as an alternative coagulant aid. Fe-BTC was prepared by hydrothermal technique using ferric chloride hexahydrate (FeCl3·6H2O) combined with 1,3,5-benzenetricarboxylic acid (trimesic acid, H3BTC) in deionized water and ethanol. X-ray diffractometry and Fourier transform infrared spectroscopy were used to characterize the property of Fe-BTC. Three quadratic models of the four factors including Fe-BTC dosage, pH, initial lignin concentration, and slow mixing time were defined with lignin removal efficiency as a response. Treatment efficiency of lignin removal was 50-80% for experimental data and 60-80% for predicted values. Optimal condition was 1 g/L of Fe-BTC dosage, pH 4, and 50 ppm of initial lignin concentration without slow mixing giving 58.34% lignin removal efficiency. The pH of treated samples was below 3 after all processes. Results showed that Fe-BTC enhanced separation of lignin by coagulation-flocculation. Adsorption-charge neutralization is the main mechanism of this process at acidic pH. Fe-BTC separated the wastewater into three layers with Fe-BTC powder at the bottom, lignin sludge in the middle, and clear supernatant at the top. Lignin sludge can be reused and recycled for use in other applications.

Mycoremediation of unsterilized PCDD/F-contaminated field soil was successfully demonstrated by solid-state fermentation coupled with Pleurotus pulmonarius utilizing a patented incubation approach. The experiments were carried out in four setups with two as controls. The contaminated soil was homogenously mixed with solid inocula, 1:0.5 dry w/w, resulting in an initial concentration of 4432 ± 623 ng WHO-TEQ kg−1. After a 30-day incubation under controlled conditions, the overall removal (approx. 60%) was non-specific. The removal was attributed to degradation by extracellular ligninolytic enzymes and uptake into the fruiting tissue (~110 ng WHO-TEQ kg−1 of mushroom). Furthermore, less recalcitrant chlorinated metabolites were found, implying ether bond cleavage and dechlorination happened during the mycoremediation. These metabolites resulted from the complex interaction between P. pulmonarius and the indigenous microbes from the unsterilized soil. This study provides a new step toward scaling up this mycoremediation technique to treat unsterilized PCDD/F-contaminated field soil.

This study aims to offer insights into how ciprofloxacin (CIP) impact bacterial community structures in the Sponge-MBR process when CIP is spiked into hospital wastewater. We found that the CIP toxicity decreased richness critical phylotypes such as phylum class ẟ-, β-, ɣ-proteobacteria, and Flavobacteria that co-respond to suppress denitrification and cake fouling to 37% and 28% respectively. Cluster analysis shows that the different community structures were formed under the influence of CIP toxicity. CIP decreased attached growth biomass by 2.3 times while increasing the concentration of permeate nitrate by 3.8 times, greatly affecting TN removal by up to 26%. Ammonia removal was kept stable by inflating the ammonia removal rate (p 0.003), with the wealthy Nitrospira genus guaranteeing the nitrification activity. In addition, we observed an increasing richness of Chloroflexi and Planctomycetes, which may play a role in fouling reduction in the Sponge-MBR. Therefore, if the amount of antibiotics in hospital wastewater continues to increase, it is so important to extend biomass retention for denitrification recovery.

This study was performed to evaluate the use of white rot fungus, Pleurotus pulmonarius, to treat polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) in contaminated soil using solid state fermentation (SSF). The soil was collected from a long-closed pentachlorophenol plant in southern Taiwan. The non-sterilized soil with a total PCDD/F concentration of 14,000 ± 2400 ng I-TEQ kg−1 was mixed directly with the solid fungal inocula at dry w/w ratio of 1:1.4 (ratio-adjusted test) and incubated at 26 ± 2 °C in a controlled environment. The highest PCDD/F decomposition was observed during the mycelium colonization. Pearson correlation coefficient (r) studied during this period (35 days) indicated that laccase had no significant correlation (r = −0.53), while manganese peroxidase had a strong positive correlation (r = 0.88) with PCDD/F decomposition efficiency. After 72 days, the more toxic congeners, tetra- and penta-CDD/Fs were removed to non-detectable levels. Meanwhile, the removal efficiencies of hexa-, hepta-, and octa-CDD/Fs were >80%, >97%, and >90%, respectively. The simultaneous degradation of low and high chlorinated DD/Fs suggested that overall removal was nonspecific. The overall PCDD/F removal was 96%, and the residual concentration (276 ng I-TEQ kg−1) was below the regulatory control limit (1000 ng I-TEQ kg−1). In conclusion, this study shows that P. pulmonarius via SSF can successfully remediate the PCDD/F-contaminated field soil. Furthermore, this SSF technique overcame the well-known intractability of PCDD/F biodegradation in non-sterilized soil, making it promising for actual field application.

Food waste composting was used to treat highly fuel oil-contaminated soil (two particle size fractions - fine 1.3 cm). The initial fuel oil concentrations in the fine and coarse piles were 12,000 and 11,850 mg/kg, respectively. After 45-day incubation, the removal efficiencies of the fine and coarse piles were 82% and 93%, respectively. Residual fuel oil concentration (847 mg/kg) in the coarse pile met the Taiwan EPA standard limit (1000 mg/kg). The results indicated that the soil particle size fraction affected the efficiency of the composting treatment. Besides, emissions of oxygenated volatile organic compounds (OVOCs) and BTEXs from the food waste composting treatment were investigated. Ketones and toluene were the most abundant species of OVOCs and BTEXs, respectively. This study demonstrated that food waste composting would be a promising treatment technology for highly fuel oil-contaminated soil.

The Houjing River, which flows by large industrial complexes in southwestern Taiwan, has been seriously polluted with benzene, toluene, ethylbenzene, and xylene (BTEX). Using Spearman’s analysis of...

Sponge membrane bioreactor (Sponge-MBR) has been proposed as an effective process to eliminate organic matters, nitrogen compounds and control fouling for domestic and hospital wastewater treatment. However, tannery wastewater with extremely organics and salt concentrations poses a great threat to the stability of biological treatment processes, rapidly increasing fouling and cost of physio-chemical treatment. This study examined the performance of Sponge-MBR to treat real tannery wastewater under organic loading rates of 1.38 ± 0.59 and 2.05 ± 0.61 kg COD m−3 d−1. The results showed that tannery wastewater vastly inhibited the growth of suspended biomass (MLVSS/MLSS ratio of 0.3). However, such ratio has been increased up to 24% in the attached biomass of sponge carriers. Up to 87 ± 14% of organic matters and 43 ± 10% of total nitrogen (TN) were eliminated even though the system suffered a high total dissolved solids (TDS) of 12,510 mg L−1. Using nitrogen balance analysis, the simultaneous nitrification-denitrification process occurred inside the sponges resulting in 21% TN removal via denitrification. Thanks to the dynamic movement of sponge carriers, the cake layer (i.e., solids and colloids) contributed only 28% of total resistance. This outcome resulted in decreasing 1.2-fold fouling rate as using sponge media in the MBR. Overall findings suggest that a low flux operation combined with sponge media (20%) in the MBR appears to be a viable option for real tannery wastewater treatment.

Houjing River, located in Kaohsiung City, is one of the most seriously contaminated rivers in Taiwan. This study analyzed the concentrations of heavy metals (As, Cd, Cr, Cu, Pb, Ni, Zn and Hg) in sediments and water samples collected from this river. Analysis of contamination factor ( C f i ) and potential ecological risk factor ( E f i ) of heavy metals in water showed that there were low grades of contamination and potential ecological risk for all heavy metals, suggesting that heavy metals in water were less likely to pose risks to the ecosystem. However, sentiment samples were found to have severe contamination levels based on ranges found in sediment quality guidelines (SQG). The average Cu concentration was almost twice as high as the upper standard values in all the guidelines. Multi-element indices were used to evaluate the synergistic effects of different metals at the sampling sites. The calculated results of different indices, the modified degree of contamination ( mC d ), Nemerow pollution index ( P N ) and potential ecological risk index ( RI ), were in good accordance. ‘Heavy’ contamination and ‘severe’ ecological risk were found at three sites, Demin, Zhuwai and Renwu. Cadmium and copper contributed the highest to the ecological risk there. Results of positive matrix factorization modeling identified four sources of heavy metal pollution in both sediments and water. Heavy metal contamination in the Houjing River is attributed to companies carrying out various industrial processes along the riverbank, including traditional metal-plating, plastic manufacture and semi-conductor packaging. Therefore, future pollution control and management plans should emphasize the strict regulation of discharge from these industrial activities.

This study used microwave-assisted hydrothermal (MHT) methodology to successfully synthesize highly crystalline perovskite-type NaTaO 3 . Calcination at 800, 850 and 900 °C was performed to evaluate MHT’s effects on NaTaO 3 ’s crystallinity, optical properties, morphology and photocatalytic performance. Grain growth-induced irregular agglomerations reduced the surface area of the calcined samples, negatively affecting photocatalytic performance. Ta O bond of sodium tantalum was detected in all samples by FTIR spectra analysis, proving the success of MHT. Based on the results of photocatalytic experiment using methyl-blue aqueous solution under both UV and visible (white-light LED) light irradiation, the non-calcined NaTaO 3 performed better than the calcined ones. Thus, calcination does not always guarantee a better photocatalytic performance of NaTaO 3 . The performance of the non-calcined NaTaO 3 exposed to five hours of visible light irradiation (60%) was less positive than that exposed to UV irradiation (90%). This photocatalyst holds promise for the treatment of wastewater in the future.

Benzophenone (BP) and its derivatives are extensively used as ultraviolet filters in modern society and increasingly being released into the environment. Co-composting of food waste with sawdust and mature compost was successfully demonstrated to treat high BP concentration (927 ± 229 mg kg−1), with a removal efficiency of 97% after 35 days of incubation. The highest biodegradation rate of 55 mg kg−1day−1 was observed at the thermophilic stage. The biodegradation followed second-order kinetics, and the half-life of BP was 1.3 days during the co-composting process. Additionally, malodorous gas emissions from the co-composting process were also analyzed. The malodorous compounds, including ammonia (NH3), hydrogen sulfide (H2S), and volatile organic sulfide compounds (VOSCs), peaked at the thermophilic phase. NH3 and H2S were the main components contributing to 92% and 7.6% of the total malodorous concentration (617 ppm). Dimethyl disulfide (28.9 ppb) and dimethyl sulfide (23.5 ppb) concentrations accounted for ∼ 58.9% of the total VOSC emitted. The malodorous emissions were positively correlated with temperature, pH, and negative with oxygen content during the co-composting. Sawdust and mature compost enhanced oxygen penetration in the compost mixture and thereby reduced odor emission. These results support that co-composting could be a technically and economically feasible treatment technology for the degradation of BP and can be used to treat other emerging organic pollutants.

The overall dioctyl terephthalate (DOTP) degradation efficiency during food waste composting was 98%. The thermophilic phases contributed to 76% of the overall degradation efficiency, followed by the maturation phase (22%), then the mesophilic phase (0.7%). The thermophilic phase had the highest specific degradation rate of 0.149 d-1. The progression of the bacterial community during the composting process was investigated to understand DOTP biodegradation. The results showed that the bacterial richness and the alpha diversity of the DOTP composting were similar to a typical composting process, indicating that the high concentration of DOTP did not hinder the thriving and evolution of the bacterial community. Additionally, Firmicutes was the most dominant at the phylum level, followed by Proteobacteria and Bacteroidetes. Bacilli was the most dominant class (70%) in the mesophilic phase, with the abundance decreasing thereafter in the thermophilic and maturation phase. Moreover, Lactobacillus sp. was the dominant species at the beginning of the experiment, which was probably responsible for DOTP biodegradation. The high removal efficiency observed in the maturation phase indicates that degradation occurs in all the composting phases, and that compost can be used to enhance natural attenuation. These findings provide a better understanding of the bacterial communities during biodegradation of DOTP and plasticizers via food waste composting and should facilitate the development of appropriate green bioremediation technologies.

In this study, mixed culture (microalgae:activated sludge) of a photobioreactor (PBR) were investigated at different inoculation ratios (1:0, 9:1, 3:1, 1:1, 0:1 wt/wt). This work was not only to determine the optimal ratio for pollutant remediation and biomass production but also to explore the role of microorganisms in the co-culture system. The results showed high total biomass concentrations were obtained from 1:0 and 3:1 ratio being values of 1.06, 1.12 g L-1, respectively. Microalgae played a dominant role in nitrogen removal via biological assimilation while activated sludge was responsible for improving COD removal. Compared with the single culture of microalgae, the symbiosis between microalgae and bacteria occurred at 3:1 and 1:1 ratio facilitated a higher COD removal by 37.5–45.7 %. In general, combined assessment based on treatment performance and biomass productivity facilitated to select an optimal ratio of 3:1 for the operation of the co-culture PBR.

In this study, composting materials of food waste (FW) and dried leaves were mixed to achieve the C/N ratio of 20, 25 and 30. Each of these ratios was turned with three frequencies: once a day (TF1), once per 2 days (TF2) and once per 3 days (TF3) to find out the optimal one. Based on the profiles of TOC, TN, TP and total humic, the optimal TF with C/N of 20, 25 and 30 was TF1, TF3, and TF2, respectively. The best composting product of each C/N ratio was used to test the growth of a number of vegetables (Cucumis sativus, Solanum lycopersicum, Momordica charantia, Ipomoea aquatica). As the result, the highest plant growth was achieved at C/N of 30 (TF3) even better than the one using chemical fertilizer. This indicates food waste and dry leaves (resources) could be recycled as a useful product at household scale.

Exposure to phthalate esters (PAEs) poses health risks to humans. Much research has been performed evaluating PAE levels in foodstuffs, river sediment and drinking water, but little attention has been paid to their presence in urban outdoor environments where human activities are highly intense. Here we evaluated PAE presence and distribution in street dust in Kaohsiung, the most industrialized city in Taiwan. Our results showed that PAEs were ubiquitous in fifty-two street-dust samples (levels of total PAEs 5.4–989.2 mg kg−1). Di-(2-ethylhexyl) phthalate was the most abundant congener observed and made up 85.0%, 79.7%, and 97.2% of the total PAEs found in industrial, residential and commercial areas, respectively. PAE levels in street dust in commercial areas (night markets) were significantly higher, suggesting a higher risk of contamination on people present in these areas (H value > χU2). In residential and commercial areas, the higher the intensity of human activity, the higher the PAE content observed. PAE content decreased progressively from the center to the outskirts of the Houjing night market, suggesting that the increased human and consumer activities inside this commercial hotspot were the main PAE source in street dust. Children had higher estimated daily intakes (DIs) than adults and dermal absorption contributed more to these levels than oral ingestion. Although all calculated DIs were below referenced danger thresholds, street dust PAEs in the area should remain an environmental concern especially since night markets play an important role in Taiwanese/Asian culture and economy. Contrary to other studies, PAEs in this study were found less related to industrial manufacturing activities but highly linked to commercial activities. These findings are relevant for future pollution prevention efforts dedicated to mitigating public exposure to PAEs. Main findings PAE levels in street dust are related to commercial activities. Night markets, an important commercial activity in Taiwan, were found to contribute considerably to PAE contamination in street dust.

The increasing usage and disposal of plastic products could cause the wide distribution of phthalate esters (PAEs) in various environmental media. In this study, six PAE compounds, namely dimethyl phthalate, diethyl phthalate, di-n-butyl phthalate, benzyl butyl phthalate, di(2-ethylhexyl) phthalate (DEHP), di-n-octyl phthalate, were analyzed in various samples collected from the major plastic industrial area of southern Taiwan, including soil, fertilizer and plastic products, for the purposes of identifying of the possible sources of PAEs and assessing the related health risk. The results show that PAEs in soil samples was dominated by DEHP, with the total concentrations in the range of 0.7 ± 0.5, 0.2 ± 0.1, and 0.3 ± 0.2 mg kg−1 for soil samples from farmland, household back gardens and the roadside, respectively. Contents of PAEs in chemical fertilizer (ND—0 0.87 mg kg−1) were higher than that in organic fertilizer (ND—0.08 mg kg−1), and PAEs concentrations (ND—316 mg kg−1) in plastic mulching films were much less than those in the other types of plastic products (ND—1719 mg kg−1), implying that major sources of PAEs in agricultural soil could be the use of chemical fertilizer and plastic products other than plastic mulching films. Health risk assessment suggested that, via the exposure to PAEs in soil, the potential non-cancer and carcinogenic risks for adults and children are minimal in most cases, except that a “moderate” carcinogenic risk for children exposure to DEHP. The results of this study can serve as a reference for further pollution prevention and environmental protection plans in relation to the industrial operation and discharge as well as the farming practices.

The Houjing River flows through Kaohsiung, the most industrialized city in southern Taiwan. In this study, heavy metal concentrations in water and sediments from samples along the river were investigated to illustrate metal contamination levels and call for the awareness of industrial pollution prevention. The heavy metal concentrations in the water samples were low and appear to pose little direct risk to aquatic life and irrigation, but heavy metal concentrations in the sediments are locally very high and present an environmental risk. Cadmium, Cu, and Zn were found in higher concentrations in the river sediments than those recommended in some sediment quality guidelines and findings of river sediments in similar studies worldwide. Hence, the ecological risk of heavy metal contamination in sediments was assessed using the pollution load index (PLI) and potential ecological risk index (RI). Three of the eleven sites sampled were found to have PLI values higher than 1 and 8 of them had ‘considerable’ to ‘very high’ RI values, suggesting a considerable ecological risk. These findings provide an insight into elemental metal contamination of the Houjing River and present a baseline data set, which will be critical for future development and environmental protection plans devised for the region.

PCDD/F-contaminated soil of a coastal region formerly involved in the production of pentachlorophenol (PCP) in Tainan City in southern Taiwan, has drawn wide concern throughout the island. This main goal of this study was to find an effective and environmentally friendly means of removing PCDD/Fs from its contaminated fields. We performed a soil washing experiment with fish extract using a combination of ultrasonification and mechanical double-blade stirring. The experiments were conducted under ambient temperature, at a soil/liquid ratio of 1:2.5, 700 rpm, and over a short duration. This combined method using fish extract removed 94.12% of the pollutant in moderately contaminated soils (5 washing cycles) and 94.51% in highly contaminated soils (10 washing cycles), mostly via particle collision and penetration. These findings highlight the benefits of PCDD/F partitioning between the particles and fish oil extract. This study is the first to use fish oil extract, a natural solvent, to treat soils highly contaminated with dioxins. Because fish oil extract is rich in non-toxic bio-surfactants (e.g., alcohols, acids, ketones, etc.), it may be used in this process to improve bioavailability and bioactivity of the soil making bio-attenuation and full remediation safer and more efficient.

In this study, titanium oxide (TiO 2 ) photocatalyst film were prepared by liquid phase deposition (LPD) using a deposition solution of boric acid (H 3 BO 3 ) and ammonium hexafluoro-titanate [(NH 4 ) 2 TiF 6 ]. The LPD-TiO 2 films were deposited on Si substrate, and soaked in the methylene blue solution under UV irradiation at room temperature. The dye decolorization efficiency was improved with the high annealing temperature. The LPD-TiO 2 films were characterized by field-emission scanning electron microscopy (FE-SEM), The constituent elements were examined by Energy Dispersive Systems (EDS). Degree of adhesion of the liquid surface to the solid surface and decolorization efficiency were examined by Contact Angle Meter and UV-Vis spectroscopy, respectively. In the optimum condition, the LPD-TiO 2 film for dye decoloriztion efficiency was 68% after UV light irradiation for 8 hr.

Dioctyl terephthalate (DOTP), a plasticizer is used as an additive in many plastic products. Disposal of DOTP into environment has been of concern because it is hardly biodegradable in nature. Therefore, the aim of this study is to investigate the biodegradation of DOTP by aerobic composting processes without bioaugmentation. The initial DOTP concentration in the compost mixture was 11,882 mg/kg, after 35-day incubation, the removal efficiency of the compost reactor was 98%. The degradation was found to follow the first-order kinetic with the half-life of 5.2 days. Food waste composting was demonstrated as a technically robust and economically competitive process for the degradation of DOTP, and that of other similar plasticizers are expected.

In this study, gaseous benzene, toluene, ethylbenzene, and o-xylene (BTEX) were extracted by passive needle trap samplers (NTS) using divinylbenzene (DVB) particles (mesh sizes 60-80, 80-100, and 100-120, respectively) as packed sorbents. An aspirating pump measured sampling flow rates of NTS, and the relations between BTEX mass and sampling flow rates were sufficient to maintain the extraction performance of these self-designed DVB-NTS. Furthermore, this investigation compared the extraction efficiency of NTS with that of the 100-microm polydimethylsiloxane solid-phase microextration (PDMS SPME) fiber when applied to sample heating products from electric-vaporization anti-mosquito mats, and the experimental results indicated that NTS effectiveness increased with decreasing adsorbent particle diameter. Substantially less mass of gaseous BTEX was extracted using 100-microm PDMS SPME fiber than with NTS of 100-120 mesh DVB for 60-min TWA sampling of anti-mosquito mats. The 100-120 mesh DVB-NTS primarily adsorbed 4.2 ng acetone, 13.3 ng dichloromethane, and 4.5-25.3 ng C10-C12 alkanes.The needle trap sampler (NTS) has been evaluated to be a device for sampling heating products from electric-vaporization anti-mosquito mats. Based on the experimental results, this investigation assessed NTS as suitable for occupational and environmental health applications.

This study reported cumulative 6-day (lag 0–5 days) relative risks (RR) and confidence intervals (CI) of daily outpatient visits for total respiratory disease (RD), asthma, and chronic airway obstruction not otherwise classified (CAO) associated with three ozone metrics (daily 1-h maximum (O3, 1 h max), 8-h average maximum (O3, 8 h max), 24-h average (O3, 24 h avg)), and an alternative oxidant indicator (Ox) in Taipei Metropolitan, using distributed lag non-linear models after controlling for potential confounders. The Ox showed the strongest association with outpatient visits for total RD (RR = 1.10, 95% CI: 1.10, 1.11) and asthma (RR = 1.18, 95% CI: 1.00, 1.39) in the cold season. The O3, 24 h avg appeared to be the optimal ozone metric associating with total RD than O3, 1 h max and O3, 8 h max based on model selection. In conclusion, outpatient visits for total RD associated with ozone vary with ozone metrics, disease and season., Highlights ► The health risk of ozone varied by RD type and by the ozone metrics applied. ► O3, 24 h avg was a better metric to associate with outpatient visits of total RD. ► Ox most correlated with outpatient visits for total RD in the cold season., The O3, 24 h avg was a better metric than O3, 1 h max and O3, 8 h max to associate with outpatient visits of total respiratory diseases.

The remediation of dioxin-contaminated soil of a specific coastal area previously employed for the manufacture of pentachlorophenol (PCP) in southern Taiwan's Tainan City has attracted much attention of researchers there. This work addresses the possibility of providing an effective and environmentally friendly option for removing PCDD/Fs from soil in that field. Soil screening/sieving was first conducted to assess particle distribution. Fine sand was observed to be the major component of the soil, accounting for more than 60% of the total mass. A combination of ultrasonification and mechanical double-blade agitation was used to facilitate the washing of the soil using the biosurfactant anaerobic compost tea. More than 85 and 95% of total removal efficiencies were achieved for moderately and highly contaminated soils after 6 and 10 washing cycles, respectively, under ambient temperature, a soil/liquid ratio 1:2.5, 700 rpm, and over a relatively short duration. These results were achieved through the collision and penetration effects of this combined treatment as well as PCDD/F partitioning between the particles and anaerobic compost tea. This study represents the first to report the use of anaerobic compost tea solvent to wash soil highly contaminated by dioxin. It was concluded that anaerobic compost tea, rich in non-toxic bio-surfactants (e.g., alcohols, humic acids), can be used to improve bioavailability and bioactivity of the soil making bio-attenuation and full remediation more efficient.

This study evaluates the effects of a sampling strategy that includes the sampling season, time period, ambient environment, and location on determining the concentrations and species of ambient volatile organic compounds (VOCs) that may affect children in primary schools. Air samples were collected from playgrounds in primary schools, with four sites near an oil refinery plant in Taoyuan and two sites in Zhongli (one site near a bus terminal and the other site in a suburban area) in Taiwan. The samples were obtained on eight occasions from August 2010 to June 2011. One sample was collected from 09:00 to 11:00 and the other was collected from 13:00 to 15:00 on each occasion using passive flow controller canisters (40 mL min−1 flow rate) assembled with silica-coated stainless steel. The United States Environmental Protection Agency Method TO-15 with Photochemical Assessment Monitoring System and Urban Air Toxics standards was used to analyze the samples. The ratios of benzene, toluene, ethylbenzene, and xylenes (BTEXs) were also estimated. This study found that the sampling location and wind direction are the main determinants to monitor the concentrations and species of ambient VOCs, and the effects from the sampling season and time period are minor. Alkane, ketone, and aromatics have been ranked as the top three categories with high concentrations, and toluene, 2-butanone, and acetone have been detected with the highest concentrations among the investigated VOCs. Several VOCs emitted from stationary sources, including propane, isoprene, n-decane, chloromethane, chloroethene, chloroethane and 1,2-dichloroethane, were detected only in Taoyuan. Higher concentrations of VOC species associated with automobiles and common community sources were detected in Zhongli but not in Taoyuan. Among BTEXs ratios, toluene/ethylbenzene ratios were as high as 31.52 (standard deviation [S.D.] = 13.53) in Taoyuan and 13.66 (S.D. = 3.87) in Zhongli. Toluene/benzene ratios were as high as 15.7 in Taoyuan and 4.30 in Zhongli. This study suggests that the susceptible population exposed to ambient VOCs should be considered in planning public service facilities and the presence of VOCs should be investigated regularly.

Microwave (MW) is applied to enhance perchloroethylene (PCE) or pentachlorophenol (PCP) removal using zero-valent iron (ZVI; Fe(0)) as the dielectric medium. ZVI has a much higher dielectric loss factor (39.5) than other media; it is capable of absorbing MW radiation rapidly to speed up the release of electrons, leading to rises of the ZVI particle surface temperature. If the MW power is continued, excessive electricity will accumulated inside ZVI particles, resulting in sparks. The results show that during the initial 5 sec (700 W), the linear aliphatic PCE has a faster decomposing rate than the ringed PCP (82.0% vs. 4.8%) because less energy is required for decomposing the linear-chlorine bond (90 kcal mol(-1)) than ring-chlorine bonds (95 kcal mol(-1)). Later the removal rate for either PCE or PCP remains the same when the exposure time is between 5 and 60 sec. Without MW irradiation, linear PCE molecules have larger surface area to contact ZVI, and hence they have better removal efficiencies than PCP molecules. Using Fe(0) as a microwave dielectric medium to treat PCE or PCP is a new and worthwhile treatment technology; it is environmentally friendly, and its use will eliminate the secondary pollution.Nanoscale iron particles are characterized by high surface-area-to-volume ratios, high specific surface area, and high surface reactivity. With a much higher dielectric loss factor, it is capable of absorbing MW radiation rapidly to speed up the release of electrons, leading to rise in temperature. The time needed to achieve a satisfactory treatment is also reduced, leading to significant saving of energy consumption to make this method cost-effective and also environmentally friendly for the industry to pursuit sustainable development.

In this study, 26,315 mg/kg of diesel oil was mixed with food waste; the mixture was subjected to composting and monitored for temperature, pH, and moisture content to assure a normal composting process. Variation of total petroleum hydrocarbon (TPH) in the compost was monitored to better understand the progress of diesel decomposition. Samples were also collected for identifying Oleiphilus species. Results showed that food waste composting is effective in decomposing diesel oil, as the TPH was reduced to 2000 mg/kg with about 90%–92% removal efficiencies at the 24th day. Eleven Oleiphilus species were isolated during various composting stages: five from the initial stage, two from the temperature-rising stage, one from the thermophilic stage, one from the temperature-recovering stage, and two from the maturing stage. These observations reveal that the food waste composting pile contained a wide variety of microorganisms, and microorganisms with different oil-decomposing capabilities developed du...

This study investigated the ozone formation mechanism and air mass trajectory via simultaneous air quality sampling around the coastal region of urban Kaohsiung. Vertical concentration profiles of O3 and its precursors (NO(subscript x) and VOCs) were sampled and measured at inland and offshore sites during eight intensive sampling periods. The intensive sampling periods were divided into three categories based on meteorological condition: the sea-land breeze period, the northeastern monsoon period, and the mixed period. Vertical profile results showed that the stratification of O3 was commonly observed at 40 out of 64 sampling sites accounting for 62.5% of the total O3 measurement. The results obtained from VOCs measurement indicated that the major species of VOCs was acetone, which accounted for 16.25-64.05% of total TVOCs- C2 in the offshore region, while the major species of VOCs in the inland region was toluene, which accounted for 6.41- 43.77 % of total TVOCs-C2. Backward trajectories showed that air pollutants emitted from land sources could transport to the offshore region, resulting in a high concentration of oversea NO(subscript x) and VOCs. Major species of VOCs with high O3 formation potential were found to be aromatics in the low atmosphere around the coastal region of metro Kaohsiung.

This study investigates the effects of sea-land breezes (SLBs) and northeastern monsoon (NEM) on the physicochemical properties of particulate matter (PM) in the atmosphere over southeastern coastal region of Taiwan Strait. The intensive PM sampling protocol was consecutively conducted for forty-eight hours. During the sampling periods, PM2.5 and PM2.5–10 were simultaneously measured with dichotomous samplers at four sites (two inland and two at offshore sites) and PM10 was measured with beta-ray monitors at these same four sites. Strong SLBs were regularly observed in the coastal region of southern Taiwan during the SLBs periods, while significant northeastern monsoons appeared during the NEM periods. The mass ratios of PM2.5/PM10 during the NEM periods were always higher than the SLBs periods. The most abundant ionic species of PM were SO4 2- , NO3 - , and NH4 + . The most common chemical compounds of PM in southern Taiwan were ammonium sulfate ((NH4)2SO4) and ammonium nitrate (NH4NO3). Carbon contents of PM during the NEM periods were higher than during the SLBs periods. The organic-to-elemental-carbon ratio (OC/EC) of PM2.5 ranged from 1.05 to 4.39 with an average of 2.26. The order of major metallic elements of PM2.5 in the SLBs and NEM periods is Fe > Ca > K > Al > Mg > Zn > Pb and Ca > Fe > Al > K > Mg > V > Ni, respectively, and of PM2.5–10 is Ca > K > Al > Fe > Mg > Zn and Fe > Ca > Al > K > Mg > V > Ni, respectively. This study reveals that the accumulation of PM offshore, due to land breezes, influences the tempospatial distribution of PM at the coastal region in southern Taiwan. Moreover, the nss-[SO4 2]/[Na + ] ratio regarded as a PM pollution index, is more suitable than the [NO3 ]/[Na + ] ratio.

In this research, MW energy is combined with nanoscale zero-valent iron (ZVI or Fe 0 ) particles suspended in aqueous chlorobenzene (CB) solution for enhancing the CB decomposition. When MW energy is applied at 250 W for 300 s to irradiate 100 mg/L of CB solution containing 1 g ZVI particles, the CB activation energy is decreased by 8.6 kJ/mol (21.9–13.3 kJ/mol) so that the CB removal efficiency is enhanced 4.6 times (82.8% vs. 18.1%). The reductive dechlorination reaction occurs at the surface of zero-valent iron particles; the organic substance in the bulk of the solution diffuses to the iron particle surface to contact the iron particle for the reductive dechlorination reaction to occur. When MW radiation penetrates the solution to reach the surface of suspended Fe 0 particles, the radiation accelerates the iron oxidization, and increases the surface activity site thus enhancing the CB decomposition rate. Hence the MW-induced zero-valent iron can reduce the CB activation energy that contributes to the enhanced rate of CB removal.

To estimate nutrient budgets, water samples were collected at 16 sites in Tapong lagoon from January 2004 through April 2005 and the parameters of water quality were analyzed immediately after collection. These data were used to build a box model for calculating nutrient budgets of the lagoon. We estimated the net amount of nutrient fluxes into (coming from creeks) and out (from tidal inlet) of the lagoon and calculated the total amount of nutrient that deposits into the sediment in a full tidal cycle. During January and April, nutrients (including nitrate, nitrite and ammonia) accumulated in the lagoon, but phosphate, total phosphate and suspended solids were flushed out of the lagoon from the tidal inlet. In addition, a huge amount of suspended solids (13–15 tons per tidal cycle) flew from the lagoon to the adjacent ocean through the inlet-outlet channel.

An open-path Fourier transform infrared spectroscopy (OP-FTIR) system was set up for 3-day continuous line-averaged volatile organic compound (VOC) monitoring in a paint manufacturing plant. Seven VOCs (toluene, m-xylene, p-xylene, styrene, methanol, acetone, and 2-butanone) were identified in the ambient environment. Daytime-only batch operation mode was well explained by the time-series concentration plots. Major sources of methanol, m-xylene, acetone, and 2-butanone were identified in the southeast direction where paint solvent manufacturing processes are located. However, an attempt to uncover sources of styrene was not successful because the method detection limit (MDL) of the OP-FTIR system was not sensitive enough to produce conclusive data. In the second scenario, the OP-FTIR system was set up in an industrial complex to distinguish the origins of several VOCs. Eight major VOCs were identified in the ambient environment. The pollutant detected wind-rose percentage plots that clearly showed that ethylene, propylene, 2-butanone, and toluene mainly originated from the tank storage area, whereas the source of n-butane was mainly from the butadiene manufacturing processes of the refinery plant, and ammonia was identified as an accompanying reduction product in the gasoline desulfuration process. Advantages of OP-FTIR include its ability to simultaneously and continuously analyze many compounds, and its long path length monitoring has also shown advantages in obtaining more comprehensive data than the traditional multiple, single-point monitoring methods.

Although most coke oven research is focused on the emission of polycyclic aromatic hydrocarbons, well-known carcinogens, little has been done on the emission of volatile organic compounds, some of which are also thought to be hazardous to workers and the environment. To profile coke oven gas (COG) emissions, we set up an open-path Fourier transform infrared (OP-FTIR) system on top of a battery of coke ovens at a steel mill located in Southern Taiwan and monitored average emissions in a coke processing area for 16.5 hr. Nine COGs were identified, including ammonia, CO, methane, ethane, ethylene, acetylene, propylene, cyclohexane, and O-xylene. Time series plots indicated that the type of pollutants differed over time, suggesting that different emission sources (e.g., coke pushing, quench tower, etc.) were involved at different times over the study period. This observation was confirmed by the low cross-correlation coefficients of the COGs. It was also found that, with the help of meteorological analysis, the data collected by the OP-FTIR system could be analyzed effectively to characterize differences in the location of sources. Although the traditional single-point samplings of emissions involves sampling various sources in a coke processing area at several different times and is a credible profiling of emissions, our findings strongly suggest that they are not nearly as efficient or as cost-effective as the continuous line average method used in this study. This method would make it easier and cheaper for engineers and health risk assessors to identify and to control fugitive volatile organic compound emissions and to improve environmental health.

A reaction mixture containing DDT (1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane), methylene green (as the photosensitizer), and triethylamine (as the electron donor) in acetonitrile:water (1:1) was irradiated by an ordinary 150-W GE-Miser spotlight to facilitate visible-light photosensitized DDT dehalogenation. The intermediates and reaction products were identified by GC/MS (gas chromatography/mass spectrometer) and NMR (nuclear magnetic resonance). The photosensitized dehalogenation method partially degraded DDT via an electron transfer relay mechanism. Results indicate that DDT lost about three chlorines after a total of 19 days of irradiation. Aliphatic chlorines were found to be removed easier than aromatic chlorines. Various types of reductants were compared for electron donation efficiency, and photosensitizer concentration was optimized for our reaction system. In most cases, clean and simple dechlorinated products were observed. The proposed photosensitized reduction was coexisted with a thermal elimination effect for the first chlorine removal of DDT, and the photosensitized electron transfer reduction was shown to be the dominating mechanism responsible for further dechlorination after the initial stage. A sequential dechlorination pathway was proposed, with each successive dehalogenation, the reaction proceeds more slowly. The results have shown the feasibility of utilizing visible light, nontoxic dyes and electron donors to render a toxic compound less toxic and to enhance the natural carbon regeneration rates.

Valuable metal materials can be recovered from spent nickel-metal hydride (NiMH) batteries. However, little attention has been paid to the metal compositions of individual components of NiMH batteries, although this is important for the selection of the appropriate recycling process. In this study, NiMH batteries were manually disassembled to identify the components and to characterize the metals in each of these. A preliminary economic analysis was also conducted to evaluate the recovery of valuable metals from spent NiMH batteries using thermal melting versus simple mechanical separation. The results of this study show that metallic components account for more than 60% of battery weight. The contents of Ni, Fe, Co, and rare earth elements (REEs) (i.e., valuable metals of interest for recovery) in a single battery were 17.9%, 15.4%, 4.41%, and 17.3%, respectively. Most of the Fe was in the battery components of the steel cathode collector, cathode cap, and anode metal grid, while Ni (90%) and Co (90%) were mainly in the electrode active materials (anode and cathode metal powders). About 1.88 g of REEs (Ce, La, and Y) could be obtained from one spent NiMH battery. The estimated profits from recovering valuable metals from spent NiMH batteries by using thermal melting and mechanical processes are 2,329 and 2,531 USD/ton, respectively, when including a subsidy of 1,710 USD/ton. The findings of this study are very useful for further research related to technical and economic evaluations of the recovery of valuable metals from spent NiMH batteries.The spent nickel-metal hydride (NiMH) batteries were manually disassembled and their components were identified. The metals account for more than 60% of battery weight, when Ni, Fe, Co, and rare earth elements (REEs) were 17.9%, 15.4%, 4.41%, and 17.3%, respectively, in a single battery. The estimated profits of recovering valuable metals from NiMH batteries by using thermal melting and mechanical processing are 2,329 and 2,531 USD/ton, respectively, when including a subsidy of 1,710 USD/ton. These findings are very useful to develop or select the recovery methods of valuable metals from spent NiMH batteries.

This study applies a thermal separation process (TSP) to recover Fe, Mn, and Zn from hazardous spent zinc–carbon and alkaline batteries. In the TSP, the batteries were heated together with a reducing additive and the metals in batteries, according to their boiling points and densities, were found to move into three major output materials: slag, ingot (mainly Fe and Mn), and particulate (particularly Zn). The slag well encapsulated the heavy metals of interest and can be recycled for road pavement or building materials. The ingot had high levels of Fe (522,000 mg/kg) and Mn (253,000 mg/kg) and can serve as an additive for stainless steel-making processes. The particulate phase had a Zn level of 694,000 mg/kg which is high enough to be directly sold for refinement. Overall, the TSP effectively recovered valuable metals from the hazardous batteries.

In this study, 10% CuO/Al2O3 catalyst was used in a catalytic wet-air oxidation process to remove chemical oxygen demand (COD) and color from experimentally designed wastewater containing lignin. The catalyst was prepared using an impregnation method and was characterized by X-ray diffraction (XRD), atomic absorption spectroscopy (AAS), and Brunauer-Emmett-Teller method (BET) for surface area before use. A series of Box-Behnken design (BBD) experiments were used to identify the conditions (temperature, pressure, reaction time, and catalysts) necessary for the COD removal process. The predicted model had R2 and R2adj correlation coefficients of 0.98 and 0.97, respectively. Pressure only and the interaction effect between temperature and pressure were found to have a significant effect on COD removal (both confidence interval [CI] 95%). Finally, response surface methodology (RSM)-optimized results suggested that 92% of COD could be removed in 1 L of experimental wastewater with a lignin concentration 350 g/L in 120 min under the following conditions: a reaction temperature of 185 °C, a pressure of 10 bars, and catalyst loading of 1 mg/L. The experiment, performed in triplicate, yielded a COD removal of 90±2%. The results are believed to be of importance to pulp and paper industrial wastewater treatment and other similar applications.Catalytic wet-air oxidation (CWAO) has been used as an alternative to overcome problems related to the high temperatures and pressures required by the traditional wet-air oxidation. CWAO has been widely applied to treat various industrial wastewaters. To reduce the overall operational cost, it is necessary to identify the optimal condition required when designing wastewater treatment plant processes. In this work, the authors had successfully demonstrated the application of response surface methodology (RSM) with the Box-Behnken design (BBD) as a means of elucidating the complicated interaction effects between parameters.

Emissions of volatile organic compounds (VOCs), particularly those from industrial sources, have been of substantial concern because they have had adverse effects on the nearby environment and human health. In this study, the effect of altitude on the distributions of VOCs from petrochemical industrial sources was studied by analyzing the VOC concentrations at ground level and three different altitudes (100, 300, and 500 m above the ground) during three monitoring seasons from 2009 to 2010 and assessing the results by principal component analysis (PCA) and cluster analysis. Kaohsiung city in southern Taiwan, known for its high levels of air contaminants due to many pollution-intensive industries in the city, was selected as the area to be examined. Of various types of aliphatic and aromatic hydrocarbons being detected, acetone and toluene were the dominant VOC species with relatively high concentrations. By PCA application and cluster analysis, aromatic and aliphatic compounds were found to be the main VOCs accounting for the maximum variance of the data observed at ground level and high altitude, respectively. The presence of mono-aromatic hydrocarbons at ground level suggested an important contribution from traffic, while the presence of both saturated and unsaturated hydrocarbons at high altitudes was likely to be due to the local petrochemical industries given the heights of flare stacks in the examined areas and short lifetimes of unsaturated hydrocarbons such as alkenes. 3-D loading plots exhibited clear grouping of the VOCs in terms of their chemical structures and/or physicochemical characteristics for the data at ground level and 500 m and less clear differentiation for the data at 100 and 300 m, possibly resulted by atmospheric dispersion and mixing. The influence of altitude on the VOC distributions appeared not to be negligible and was greatly impacted by the location (e.g., height) of emission sources and the physicochemical properties of the VOCs including their molecular weights/sizes and lifetimes in the atmosphere. These findings prove the complications in the current knowledge of VOC pollution and are of help in managing the adverse impacts on the environment and public health by VOCs from industrial or other sources.

A decay-adjusted chemical mass balance (CMB) model has been used to estimate the contributions of gasoline vapor and highway vehicle emissions to volatile organic compound (VOC) concentrations measured at two receptor sites in Atlanta, GA. A new empirical method is proposed for estimating decay factors for VOC species, to account for reaction rates that differ across compounds, and thus fractionate source profiles during transport to a receptor. The adjusted CMB model and a standard CMB model were applied to synthetic test cases, as well as to data from the 1990 Atlanta Ozone Precursor Monitoring Study (Purdue et al. , 1992, EPA/600/R-92/157, U.S. Environmental Protection Agency). A principal components analysis source apportionment method was also applied to the Atlanta data. In the test cases, the adjusted CMB model corrected biases in standard CMB results that were due to VOC decay. At both receptor sites in Atlanta, the average contribution of vehicle-related emissions was approximately 70% of total nonmethane organic compounds. For most of the Atlanta samples, adjusting for decay resulted in small improvements in the agreement between CMB-predicted and observed concentrations of individual VOCs, but did not significantly change the estimated emissions contributions.

Objective This study investigated whether outpatient visits of acute upper respiratory infections for children aged less than 15 years are associated with temperature, air pollutants and circulating respiratory viruses in Taipei, Taiwan, from 2003 to 2007. Methods Outpatient records for acute upper respiratory infections (ICD9 CM codes: 460, 462, 463,464, 465.9 and 487) in a randomly selected sample (n=39,766 children in 2005) was used to estimate the cumulative relative risks (RR) associated with average temperature lasting for 8 days (lag 0–7 days), air pollutants (NO2, O3 and PM2.5) lasting for 6 days (lag 0–5 days), and virus-specific positive isolation rate lasting for 11 days (lag 0–10 days) using distributed lag non-linear models after controlling for relative humidity, wind speed, day of week, holiday effects and long-term trend. Results Average temperature of 33 °C was associated with the lowest risk for outpatient visits of acute upper respiratory infections. Relative to 33 °C, cumulative 8-day RR was highest at 15 °C of ambient average temperature [RR=1.94; 95% confidence interval (CI): 1.78, 2.11]. With the first quartile as reference, cumulative 6-day RRs were 1.25 (95% CI: 1.21, 1.29) for NO2, 1.04 (95% CI: 1.01, 1.06) for O3, and 1.00 (95% CI: 0.98, 1.03) for PM2.5 at the 95th percentile. Per-standard deviation (SD) increase of virus-specific isolation rate for influenza type A (SD=13.2%), type B (SD=8.76%), and adenoviruses (SD=5.25%) revealed statistical significance for overall 11-day RRs of 1.02 (95% CI: 1.01, 1.03), 1.05 (95% CI: 1.03, 1.06) and 1.04 (95% CI: 1.03, 1.05), respectively. Conclusions Current study suggested a positive association between outpatient visits for acute upper respiratory infections and ambient environment factors, including average temperature, air pollutants, and circulating respiratory viruses., Highlights ► Outpatient visits of acute upper respiratory infections highly associated with lower average temperature. ► Daily concentrations of NO2 and ozone caused greater risks than particulate on acute upper respiratory infections. ► Isolation rates of influenza type A/B & adenoviruses were significantly allied with high acute upper respiratory infection.

An aqueous reaction mixture containing perchloroethylene (PCE), a photosensitizer, and an electron donor was irradiated by visible lamps to facilitate a sunlight-sensitized dechlorination reaction. Various types of lamps, electron donors, and photosensitizers were examined, to compare the rates of dechlorination. Of the six photosensitizers evaluated, methylene blue was the most effective. Electron donors varied in effectiveness, as follows: trimethylamine > triethylamine > tributylamine. The intermediates and reaction products were identified by a purge-and-trap gas chromatography mass spectrometer system. The photosensitized dechlorination method degraded PCE via an electron-transfer-relay mechanism. Degradation products identified were trichloroethylene, dichloroethylenes, and chloroethylene. It seems a sequential dechlorination pathway was followed. The PCE dechlorination in a natural sunlight irradiation test was shown to be more effective than any of the simulated visible light sources. The result supports the feasibility of future development of solar-powered dechlorination remediation systems with the use of sunlight, nontoxic dyes, and electron donors.

The superior oil absorption capacity of recycled polypropylene (PP) fiber and waste tire powder were used to recover spilled engine oil. We used ASTM F726-99 method to evaluate oil adsorbing capability of PP fiber and found it to have a large, rapid oil sorption capacity. However, its lack of elasticity dramatically limited that capacity after repeated use. Tire powder, which absorbs less oil more slowly, is more elastic than PP fiber and can be used repeatedly up to a hundred times without losing its oil adsorption capability. We combined PP fiber and tire powder to develop a composite material capable of recovering greater amounts of oil than any of its components. This composite can be use repeatedly for at least 100 times. Thus, the material cost for recovering 1 ton of spilled oil is about USD $0.03, making it very competitive on the market.

Sediment samples were analyzed for di-(2-ethylhexyl) phthalate (DEHP), an organic endocrine disruptor, in Houjing River in southern Taiwan. The average DEHP concentration at 10 sampling locations, spanning from upper, middle, and lower segments of the stream, was calculated at 3.81 ± 6.36 mg kg −1 dry wt. Highest concentration was recorded at the Jhongsing Bridge (20.22 mg kg −1 dry wt.) near the Dashe Industrial Park, followed by the Renwu Bridge (8.93 mg kg −1 dry wt.) near the Renwu Industrial Park. The surface sediment concentration of DEHP was found to be higher in the dry season (October and December), and lower in the wet (flood) season (August), indicating that sources of DEHP remained active and continued to recharge the Houjing River. Vertical sediment core analysis revealed that highest concentration occurred at the depth of 40–60 cm, indicating that historical discharges of DEPH may have been higher than recent years. Domestic comparison of DEHP concentrations in sediment from highest to lowest could be categorized as northern, southern, central, and eastern Taiwan, respectively, and seemed to be positively correlated with population density and/or industrial activity. Compared to other countries, DEHP concentration of the Houjing River was relatively higher than rivers studied in Japan, Germany, Italy, and Malaysia, and was relatively lower than the Aire and Trent Rivers in the United Kingdom.