Surfactant Treatment for Efficient Gene Detection of Enteric Viruses and Indicators in Surface Water Concentrated by Ultrafiltration

Food and Environmental Virology - The hollow fiber ultrafiltration (HFUF)-based microbial concentration method is widely applied for monitoring pathogenic viruses and microbial indicators in...     

Suppressive effect of polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and dioxin-like polychlorinated biphenyls transfer from feed to eggs of laying hens by activated carbon as feed additive

In this study, we investigated the suppressive effect of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (DL-PCBs) transfer from the feed to the eggs of laying hens by using activated carbon as a feed additive. Four groups of six hens (White Leghorn egg-layers; age, 11 weeks) were housed as two control groups and two exposure groups for a period of 20 weeks. Two control groups were fed with either the basal feed “Control” or basal feed additing activated carbon “Control + C”. Another two exposure groups were fed with feed contaminated (about 6 ng TEQ kg⁻¹ feed) by standard solutions of PCDDs/PCDFs and DL-PCBs “Exposure” alone and contaminated feed adding activated carbon “Exposure + C”. There was no significant effect on each groups for the growth rate, biochemical blood components, and egg production: these were around the standard levels for poultry in general. Moreover the results in this study showed the availability of activated carbon as a feed additive owing to the reduction in the risk of food pollution by PCDDs/PCDFs and DL-PCBs. The concentration in the eggs of the Exposure group gradually increased following the start of egg-laying but reached a steady state after about 1 month. In contrast, the concentration for the Exposure + C group was stationary and below the maximum EU level (6 pg TEQ g⁻¹ fat). In comparison to the Exposure group, the Exposure + C group showed a significant decline in the percentage of bioaccumulation into the egg. This reduction due to activated carbon was also observed in the muscle and abdominal fat. The reductions were compound- and congener-dependent for DL-PCBs as follows: PCDDs/PCDFs, non-ortho-PCBs, and mono-ortho-PCBs were more than 90%, 80%, and 50%, respectively, irrespective of the type of tissues. Fat soluble vitamin concentrations in the eggs of the Exposure + C group showed lower trends than the Exposure group. The γ-tocopherol and α-tocopherol concentrations in eggs of Exposure + C group showed a significant reduction of about 40%. However, the addition of activated carbon into animal feed could obviate the remote potential for accidents causing unintentional food pollution with PCDDs/PCDFs and DL-PCBs.     

Odd-numbered perfluorocarboxylates predominate over perfluorooctanoic acid in serum samples from Japan, Korea and Vietnam

Perfluorooctanoic acid (PFOA) has recently attracted attention as a potential health risk following environmental contamination. However, information detailing exposure to perfluorinated carboxylic acids (PFCAs) other than PFOA is limited. We measured the concentrations of PFCAs (from perfluorohexanoic acid to perfluorotetradecanoic acid) in serum samples obtained from patients in Japan (Sendai, Takayama, Kyoto and Osaka) between 2002 and 2009, Korea (Busan and Seoul) between 1994 and 2008 and Vietnam (Hanoi) in 2007/2008. Total PFCA levels (geometric mean) were increased from 8.9 ng mL(-1) to 10.3 ng mL(-1) in Japan; from 7.0 ng mL(-1) to 9.2 ng mL(-1) in Korea; and were estimated at 4.7 ng mL(-1) in Vietnam. PFCAs of greater length than PFOA were significantly increased in Sendai, Takayama and Kyoto, Japan, and levels of long-chain PFCAs exceeded PFOA levels in serum. Among these PFCAs, perfluoroundecanoic acid (PFUnDA) was the predominant component (28.5%), followed by perfluorononanoic acid (PFNA 17.5%), perfluorodecanoic acid (PFDA 7.9%), perfluorotridecanoic acid (PFTrDA 6.1%) and perfluorododecanoic acid (PFDoDA 1.8%). Odd-numbered PFCAs (PFNA, PFUnDA and PFTrDA) were also observed in Korea and Vietnam and their presence increased significantly in Korea between 1994 and 2007/2008. The proportion of long-chain PFCAs in serum was relatively high compared to reports in Western countries. Further investigations into the sources and exposure routes are needed to predict the future trajectory of these serum PFCA levels.     

Simple technology for recycling phosphate from wastewater to farmland in rural areas

A simple technology for phosphate (P _i ) recovery has been developed using a bifunctional adsorption–aggregation agent. The bifunctional agent was prepared by soaking calcium silicates in hydrochloric acid solution. Importantly, recyclable calcium silicates were available almost free of charge from the cement industry and also from the steel industry. The acid treatment was essential not only for enhancing the ability of calcium silicates to remove P _i from aqueous solution but also for enabling the high settleability of removed P _i . On-site experiments using a mobile plant showed that approximately 80% P _i could be recovered from anaerobic sludge digestion liquor at a wastewater treatment plant. This technology has the potential to offer a simple, compact service for recycling P _i from wastewater to farmland in rural areas.     

Identification of a dynamic lake model by the group method of data handling: An application to lake ontario

A revised algorithm of the group method of data handling (GMDH) is used to model and identify water quality dynamics in Lake Ontario. The state variables in the model are corrected chlorophyll a, volume-averaged over the top 20 m, and soluble reactive phosphorus in three layers, 0–20 m, 20–40 m and from 40 m to bottom. Inputs are the average quarterly temperatures for each layer and the total phosphorus loadings. Two kinds of model are developed: recursive and iterative; they are used to simulate long-term predictions for three different hypothetical rates of phosphorus loading. Results show that GMDH can be usefully employed to develop lake models with a very low expense of manpower and computer time. This exercise compares well with other large-scale modelling efforts of Lake Ontario, even if necessarily more limited in scope.     

Unique bioconcentration characteristics of new aryl fluoroalkyl ethers in common carp (Cyprinus carpio)

The bioconcentration factors (BCFs) of seven new aryl fluoroalkyl ethers--four bis-4-tetrafluoroethoxyphenyl-type (bis-type) compounds and three mono-4-tetrafluoroethoxyphenyl-type (mono-type) compounds--were obtained by bioconcentration tests using common carp. The BCFs of 4 of the 7 ethers were higher than 5000, indicating their high bioconcentration potential. The bioconcentration characteristics of the bis-type compounds were different from those of the mono-type compounds and non-fluoro diphenylmethanes with a similar skeleton structure to the bis-type compounds, in taking longer to reach a plateau and having a slower elimination rate and in their distribution patterns in the fish body. The BCF of 1 bis-type compound was much higher than the value predicted by an accepted correlation equation between BCF and P(ow). In addition, the logP(ow) of the bis-type compounds calculated by commercially available computer software was remarkably different from that measured.     

Evaluation of activated carbon fiber filter for sampling of organochlorine pesticides in environmental water samples

A simple method for quantitative analyses of organic chlorine pesticides (OCPs) in environmental water samples such as rainwater, river water and seawater using activated carbon fiber filters (ACFF) is described. ACFF was used as adsorbent to collect the chemicals in water samples. The collection of OCPs was completed almost for one day by stirring the mixture of the sample and the ACFF chips at room temperature. The adsorbed OCPs on the ACFF could be extracted easily with toluene-ethanol (4:1) mixed solvent. The purified extract by a florisil column chromatograph was followed by the analysis using high-resolution gas chromatograph/high-resolution mass spectrometer. Recoveries of OCPs spiked to actual samples such as rainwater, river water and seawater samples were approximately more than 80%, and the coefficients of variations were within 10%. This method was applied to the actual samples and was confirmed to be applicable for monitoring sub-ng/l level OCPs in environmental water samples.     

Fabrication Mechanical Properties of Unidirectional Jute/PP Composites Using Jute Yarns by Film Stacking Method

This paper mainly focuses on the fabrication process of long fibre reinforced unidirectional thermoplastic composites made using both natural (untreated) treated jute yarns. Jute yarns were wound in layers onto a metallic frame. Polypropylene films were inserted between these layers and compression moulded to fabricate unidirectional jute/PP composite specimens. Static mechanical properties were evaluated from tensile three point bending tests. Pre- post-failure examination were carried out on the test specimens using optical scanning electron microscopy to analyse the test results and investigate the correlations between their impregnation state, processing conditions, mechanical performances and fracture morphologies. For the unidirectional jute/PP film-stacked composites, the results indicated that the processing condition at the moulding temperature of 160°C and moulding pressure of 2.0 MPa for 15 min was ideally suited to obtain optimized properties. Improved wettability of resin melts due to complete matrix fusion at this processing condition facilitated thorough impregnation with minimum microstructural imperfections (microvoids) being generated. Jute/PP composites that contained treated jute yarns have shown superiority in tensile bending properties. Jute yarns polished or coated with PVA/PP (polyvinyl alcohol/polypropylene) must have contributed positively to fibre/matrix interfacial interactions leading to matrix to fibre effective stress transfer, thereby improving their reinforcing effects. Tensile strength and modulus of PP resin increased by approximately 285% and 388%, respectively, due to 50 wt% reinforcement by natural jute yarns. Further improvements in strength and modulus were achieved by approximately 14% and 10%, respectively, when treated yarns were used . The maximum bending stress modulus of jute/PP composites containing untreated yarns were approximately 190% and 460% higher than those of the virgin PP materials, and bending properties were improved by further 11% and 23%, respectively, due to coating treatments on the yarn surface.     

The synergistic effects of hydrogen peroxide and elevated seawater temperature on the metabolic activity of the coral <Emphasis Type="Italic">Galaxea fascicularis</Emphasis>

We examined quantitative changes in the metabolism of the coral Galaxea fascicularis caused by increases in both hydrogen peroxide (H₂O₂) concentration and seawater temperature. Seawater temperatures were maintained at 27 or 31°C in a well-controlled incubation chamber, and three levels of H₂O₂ concentration (0, 0.3, 3.0 μM) were used in experimental treatments. Gross primary production, calcification rates and respiration rates were all affected by increased H₂O₂ concentrations and high seawater temperatures. Individual treatments of high H₂O₂ or elevated seawater temperature alone caused significant declines in coral photosynthesis and calcification rates within the 3-day incubation period. The synergistic effect of high H₂O₂ combined with high seawater temperature resulted in a 134% increase in respiration rates, which surpassed the effect of either H₂O₂ or high seawater temperature alone. Our results suggest that both high H₂O₂ concentrations and elevated temperatures in seawater can strongly affect coral metabolism; however, these effects cannot be estimated by simply summing the effects of individual stress parameters.