The Presence of Norovirus and Adenovirus on Environmental Surfaces in Relation to the Hygienic Level in Food Service Operations Associated with a Suspected Gastroenteritis Outbreak

Norovirus (NoV) gastroenteritis outbreaks appear frequently in food service operations (FSOs), such as in restaurants and canteens. In this study the presence of NoV and adenovirus (AdV) genomes was investigated on the surfaces of premises, especially in kitchens, of 30 FSOs where foodborne gastroenteritis outbreaks were suspected. The objective was to establish a possible association between the presence of virus genomes on surfaces and a visual hygienic status of the FSOs. NoV genome was found in 11 and AdV genome in 8 out of 30 FSOs. In total, 291 swabs were taken, of which 8.9% contained NoV and 5.8% AdV genome. The presence of NoV genomes on the surfaces was not found to associate with lower hygiene level of the premises when based on visual inspection; most (7/9) of the FSOs with NoV contamination on surfaces and a completed evaluation form had a good hygiene level (the best category). Restaurants had a significantly lower proportion of NoV-positive swabs compared to other FSOs (canteens, cafeteria, schools etc.) taken together (p = 0.00014). The presence of a designated break room for the workers was found to be significantly more common in AdV-negative kitchens (p = 0.046). Our findings suggest that swabbing is necessary for revealing viral contamination of surfaces and emphasis of hygiene inspections should be on the food handling procedures, and the education of food workers on virus transmission.     

Accumulation of heavy metals in Spinacia oleracea irrigated with paper mill effluent and sewage

The present study on heavy metal contamination in soil and their accumulation in edible part (leaves) and roots of Spinacia oleracea (Spinach) on irrigation with paper mill effluent (PME)/sewage revealed that there was significant increase in the nickel (Ni, +227.17 %) content of the soil irrigated with PME, whereas in the soil irrigated with sewage chromium (Cr, +274.84 %), iron (Fe, +149.56 %), and cadmium (Cd, +133.39 %), contents were increased appreciably. The value of enrichment factor (EF) for Ni (3.27) indicated moderate enrichment in PME-irrigated soil. The EF of Fe, zinc (Zn), Cd, and Cr were <2 in PME effluent-irrigated soil which showed deficiency of minimal enrichment. In sewage irrigated soil, EF value for Cr, Fe, and Cd indicated moderate enrichment, while the values for Zn and Ni indicated deficiency of minimal enrichment. Among various metallic concentrations, the maximum concentration of Fe was observed in leaves (400.12?±?11.47 mg/kg) and root (301.41?±?13.14 mg/kg) of S. oleracea after irrigation with PME, whereas the maximum concentrations of Fe was found in leaves (400.49?±?5.97 mg/kg) and root (363.94?±?11.37 mg/kg) of S. oleracea after irrigation with sewage for 60 days. The bioaccumulation factor value was found maximum for Cd (2.23) in the plants irrigated with PME while that of Fe (0.90) in the plants irrigated with sewage. The undiluted use of PME/sewage for irrigation increased the concentration of Cr, Cd, Zn, Ni, and Fe metals which were accumulated in S. oleracea, posing a potential threat to human health from this practice of irrigation.     

Contribution of anthropogenic aerosols in direct radiative forcing and atmospheric heating rate over Delhi in the Indo-Gangetic Basin

Introduction  

The present work is aimed to understand direct radiation effects due to aerosols over Delhi in the Indo-Gangetic Basin (IGB) region, using detailed chemical analysis of surface measured aerosols during the year 2007.     

Variability in host plant chemistry: behavioural responses and life-history parameters of the Colorado potato beetle (Leptinotarsa decemlineata)

Summary. Many studies investigating effects of plant chemicals on herbivore performance have reported contradictory results, perhaps because of possible interaction between different chemicals. Also, a herbivore’s performance is not necessarily consistent with its food or oviposition preference. Our aim was to investigate simultaneously antibiosis (larval growth and survival) and antixenosis (oviposition and feeding preferences) responses in herbivore to three plant chemicals, of which one is expected to have positive and two are expected to have negative effects. Antibiosis was measured by correlating the nitrogen and glycoalkaloid levels in host plants to the survival and adult size of Leptinotarsa decemlineata, by rearing larvae on whole plants of three potato varieties. Although host plants differed in their glycoalkaloid levels, survival rate and adult body size did not differ among beetles reared on different potato varieties. This suggests that beetles are quite robust for differences in both foliar α-chaconine and foliar α-solanine content. However, differences in antixenosis were found although they could not be directly predicted from the leaf chemistry. Females preferred to lay their eggs on the variety with high α-solanine content (Nevsky) towards which males showed a tendency to feeding preference. Overall, our results confirm that beetles are well adapted to the chemical defences of potato plants as potato varieties did not significantly affect beetle performance, but differences in oviposition preference may still result in major differences in the amount of damage inflicted on plants in the fields.     

Effect of varying pH on protein composition and yield of amaranth seed (Amaranthus blitum)

The isolation procedure of the seed proteins of Amaranthus blitum have been analyzed at different pH conditions. Qualitative studies were carried out by using electrophoretic technique sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). Mainly four protein fractions i.e. albumin, globulin, prolamin and glutelin were obtained. Protein isolates were prepared by (a) extraction at different alkaline pH (9, 10, 11 and 12) and precipitation atpH 5 and (b) extraction at pH 9 and precipitation atdifferentpH (4, 5, 6 and 7). The composition of isolates, prepared by method (a), depended on extraction pH. The isolate extracted at pH 8 was mainly composed of albumin and globulin, whereas at pH 9, 10 and 11 showed the presence of prolamin and glutelin. Electrophoretic pattern of different isolates had five major bands with molecular weight of 30, 45, 72, 84 and 90 kDt respectively. The increase of the extraction pH led to the increase in protein yield. With method (b) isolates obtained were variable in composition. At pH 7 albumin and prolamine were present, whereas at pH 4, 5 and 6 all 4 protein fractions were precipitated. According to the quantitative estimation of the albumin, globulin, prolamin and glutelin in the seed flour the contents were 26.4, 25, 5.81 and 42.7%, respectively. The results suggest that composition of protein isolates could be controlled by different extraction and precipitation pH.     

Tape-stripping as a method for measuring dermal exposure to resin acids during wood pellet production

The purpose of this study was to develop a sensitive and specific method for quantifying dermal exposure to the resin acids 7-oxodehydroabietic acid (7-OXO), dehydroabietic acid (DHAA), abietic acid (AA), and pimaric acid (PA). In addition the method was evaluated in occupational settings during production of wood pellets. Tape-strips were spiked with the substances to evaluate the recovery of the acids from the tape. The removal efficiency of the tape was assessed by tape-stripping a specified area on a glass plate spiked with resin acids. The recovery of the acids from human skin in vivo was evaluated by applying acids in methanol onto the skin of volunteers. Occupational dermal exposure to the resin acids was assessed by tape-stripping the skin of workers involved in the production of wood pellets. The resin acids were analyzed by liquid chromatography mass spectrometry (LC-MS). The limit of detection was 15 pg (7-OXO), 150 pg (DHAA), 285 pg (AA) and 471 pg (PA) per injection. The recovery from spiked tapes was in general 100%. The removal efficiency of the tape was 48-101%. Recovery tests from human skin in vivo showed a mean recovery of 27%. Quantifiable amounts of resin acids were observed on four different skin areas with an increase in exposure during a work shift. This study shows that occupational dermal exposure to resin acids can be assessed by tape-stripping and quantified by LC-MS.     

Flue Gas Desulfurization: The State of the Art

ABSTRACT

Coal-fired electricity-generating plants may use SO₂ scrubbers to meet the requirements of Phase II of the Acid Rain SO₂ Reduction Program. Additionally, the use of scrubbers can result in reduction of Hg and other emissions from combustion sources. It is timely, therefore, to examine the current status of SO₂ scrubbing technologies. This paper presents a comprehensive review of the state of the art in flue gas desulfurization (FGD) technologies for coal-fired boilers.

Data on worldwide FGD applications reveal that wet FGD technologies, and specifically wet limestone FGD, have been predominantly selected over other FGD technologies. However, lime spray drying (LSD) is being used at the majority of the plants employing dry FGD technologies. Additional review of the U.S. FGD technology applications that began operation in 1991 through 1995 reveals that FGD processes of choice recently in the United States have been wet limestone FGD, magnesium-enhanced lime (MEL), and LSD. Further, of the wet limestone processes, limestone forced oxidation (LSFO) has been used most often in recent applications.

The SO₂ removal performance of scrubbers has been reviewed. Data reflect that most wet limestone and LSD installations appear to be capable of ~90% SO₂ removal. Advanced, state-of-the-art wet scrubbers can provide SO₂ removal in excess of 95%.

Costs associated with state-of-the-art applications of LSFO, MEL, and LSD technologies have been analyzed with appropriate cost models. Analyses indicate that the capital cost of an LSD system is lower than those of same capacity LSFO and MEL systems, reflective of the relatively less complex hardware used in LSD. Analyses also reflect that, based on total annualized cost and SO₂ removal requirements: (1) plants up to ~250 MW_e in size and firing low- to medium-sulfur coals (i.e., coals with a sulfur content of 2% or lower) may use LSD; and (2) plants larger than 250 MW_e and firing medium- to high-sulfur coals (i.e., coals with a sulfur content of 2% or higher) may use either LSFO or MEL.     

Up to 399 mV bioelectricity generated by a rice paddy-planted microbial fuel cell assisted with a blue-green algal cathode

Environmental Chemistry Letters - Microbial fuel cells are used as an alternative source of energy and for microbial degradation of waste and pollutants. Different types of microbial fuel cells...     

EDTA and citric acid mediated phytoextraction of Zn, Cu, Pb and Cd through marigold (Tagetes erecta)

Phytoextraction is an emerging cost-effective solution for remediation of contaminated soils which involves the removal of toxins, especially heavy metals and metalloids, by the roots of the plants with subsequent transport to aerial plant organs. The aim of the present investigation is to study the effects of EDTA and citric acid on accumulation potential of marigold (Tagetes erecta) to Zn, Cu, Pb, and Cd and also to evaluate the impacts of these chelators (EDTA and citric acid) in combination with all the four heavy metals on the growth of marigold. The plants were grown in pots and treated with Zn (7.3 mg l(-1)), Cu (7.5 mg I(-1)), Pb (3.7 mg l(-1)) and Cd (0.2 mg l(-1)) alone and in combination with different doses of EDTA i.e., 10, 20 and 30 mg l(-1). All the three doses of EDTA i.e., 10, 20 and 30 mg l(-1) significantly increased the accumulation of Zn, Cu, Pb and Cd by roots, stems and leaves as compared to control treatments. The 30 mg l(-1) concentration of citric acid showed reduced accumulation of these metals by root, stem and leaves as compared to lower doses i.e., 10 and 20 mg l(-1). Among the four heavy metals, Zn accumulated in the great amount (526.34 mg kg(-1) DW) followed by Cu (443.14 mg kg(-1) DW), Pb (393.16 mg kg(-1) DW) and Cd (333.62 mg kg(-1) DW) in leaves with 30 mg l(-1) EDTA treatment. The highest concentration of EDTA and citric acid (30 mg l(-1)) caused significant reduction in growth of marigold in terms of plant height, fresh weight of plant, total chlorophyll, carbohydrate content and protein content. Thus EDTA and citric acid efficiently increased the phytoextractability of marigold which can be used to remediate the soil contaminated with these metals.