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Using time-lapse photography in a laboratory setting, we exposed Anodonta anatina and Unio pictorum for 4 h to algal (Chlorella vulgaris) concentrations ranging from 0.5 to 20.0 mg ash-free dry mass l−1 and to three different temperatures (11 ± 1, 15 ± 1 and 19 ± 1 °C). We analysed the proportion of mussels in locomotion, duration of locomotory activities, posterior tip movement and valve opening behaviour. The proportion of mussels in locomotion was significantly higher for A. anatina and for A. anatina was significantly lower at 11 °C. For both species, the proportion of mussels in locomotion, the duration of locomotion and movement of the posterior tip decreased with increasing algal concentration. The locomotory duration was significantly shorter in U. pictorum. In both species, valve opening peaked at intermediate algal concentrations, with the deviation from the peak being more prominent in A. anatina. Finally, we recorded a contrasting locomotory strategy for the two species (A. anatina crawled on the sediment surface, whereas U. pictorum moved through the sediment) and identified potential density dependence in behavioural adaptation.

Backgound: Experimental data were used to study the impact of pH and organic matter on soil pollution indices, with the view to express them as a function of the above two variables. Results: Data were from an experiment performed in a greenhouse using 12 wastewater and sludge treatment combinations in four replications, using Lactuca sative var Longifolia as a test plant. The experimental data were analyzed by means of linear multiple regression analysis, and the equations found were considered as revised forms for the calculation of pollution indices, which could be used as a tool for the assessment of the level of soil pollution by heavy metals. Conclusion: Tentative critical levels of the pollution indices were established on the basis of the reference revised Index PLIn. However, additional work is necessary, such as calibration of the revised indices on the basis of percentage crop yield loss, towards a more accurate assessment of the heavy metal soil pollution levels.

This study investigates the effectiveness of aquatic macrophyte and microphyte for phytoremediation of water bodies contaminated with high arsenic concentration. Water hyacinth (Eichhornia crassipes) and two algae (Chlorodesmis sp. and Cladophora sp.) found near arsenic-enriched water bodies were used to determine their tolerance toward arsenic and their effectiveness to uptake arsenic thereby reducing organic pollution in arsenic-enriched wastewater of different concentrations. Parameters like pH, chemical oxygen demand (COD), and arsenic concentration were monitored. The pH of wastewater during the course of phytoremediation remained constant in the range of 7.3–8.4, whereas COD reduced by 50–65 % in a period of 15 days. Cladophora sp. was found to survive up to an arsenic concentration of 6 mg/L, whereas water hyacinth and Chlorodesmis sp. could survive up to arsenic concentrations of 2 and 4 mg/L, respectively. It was also found that during a retention period of 10 days under ambient temperature conditions, Cladophora sp. could bring down arsenic concentration from 6 to

The current study aims to assess the infusion pattern of three important micronutrients namely copper (Cu), iron (Fe), and zinc (Zn) contents from black tea samples produced in Assam (India) and Thohoyandou (South Africa). Average daily intakes and hazardous quotient were reported for these micronutrients. Total content for Cu, Fe, and Zn varied from 2.25 to 48.82 mg kg−1, 14.75 to 148.18 mg kg−1, and 28.48 to 106.68 mg kg−1, respectively. The average contents of each of the three micronutrients were higher in tea leaves samples collected from South Africa than those from India while the contents in tea infusions in Indian samples were higher than in South African tea samples. Results of this study revealed that the consumption of 600 mL tea infusion produced from 24 g of made tea per day may be beneficial to human in terms of these micronutrients content. Application of nonparametric tests revealed that most of the data sets do not satisfy the normality assumptions. Hence, the use of both parametric and nonparametric statistical analysis that subsequently revealed significant differences in elemental contents among Indian and South African tea.

Fluoride concentrations in UK tea, including the leading supermarket economy labelled products, were determined. Fluoride ranged from 93 to 820 mg/kg in the products and 0.43 to 8.85 mg/L in the infusions. The UK supermarket economy teas contained elevated fluoride, ranging from 3.60 to 7.96 mg/L in a 2 minute brewing infusion, comparable to Chinese brick tea, indicating the use of mature leaves in their manufacture. Considering the dietary reference intake (DRI) of 4 mg/day of fluoride for an adult consuming 1 L of tea, prepared from an economy tea, containing 6.0 mg/L fluoride, 75–120% of the DRI fluoride is available for absorption by the human system in the presence of food, increasing to 150% when fasting. Excess fluoride in the diet can lead to detrimental health effects such as fluorosis of the teeth and skeletal fluorosis and consuming economy branded tea will lead to exposure.

A greenhouse experiment was conducted in Agrinion, Greece, using a randomized block design, including two variables i.e. treated municipal wastewater (TMWW), and well irrigation water (control), in six replications. The vegetable Brassica oleracea var. gemmifera (Brussels sprout) was used as a test plant. The aim of the experiment was to assess quantitatively the elemental interactions' contribution in essential elements and heavy metals, to roots, leaves, sprouts, and whole plant, by studying the interactions between the macro-, micro-elements and heavy metals, depending on their synergism or antagonism. The mean net percent elemental contribution depended on: (i) the number of interactions between the essential elements and heavy metals, (ii) the extent of synergism or antagonism of each interaction, (iii) the relation between synergistic and antagonistic interactions, (iv) the size of the contribution of each interaction, (v) the plant part and kind of plant, and (vi) the external source of the supply of nutrients and heavy metals. The quantification procedure applied proved to be relatively easy and effective and can be used in assessing the extent of nutrients and especially of heavy metal accumulation in the various plant parts and especially in the edible ones (sprouts).

This study aims at investigating the effects of the treated municipal wastewater (TMWW) on the essential and heavy metal interactions, and on the accumulation of these metals in the sprouts (edible plant part) of Brassica oleracea var gemmifera (Brussels sprouts). The statistical design included two variables: (a) TMWW, and (b) fresh irrigation water (control), in six replications, with a total of 12 experimental plots of 2.5×1.8 m = 4.5 m2 size. The following were found: a large number of interactions were identified in the sprouts (182), but only 74 of them were statistically significant. Also among them, the following interactions, i.e., Mn×N, Mn×Fe, Fe×Mn, Fe×N, N×Zn occurred not only in the sprouts, but according to our previous work, in the heads of Brassica olevacea var. Italica (Brocolli) as well, suggesting a consistency of occurrence of these interactions. However, the comparative effect of TMWW, on the interactions studied, in very few cases was found to be statistically significant, i...

Many studies have been reported in literature on the copper impregnated Dolfrwynog Bog and its flora, in particular the Cu-tolerant Armeria maritima. This paper investigates the bioavailability of ...

The impacts of a functional and a demolished copper processing works on the aquatic and terrestrial environment in the vicinity of the works was investigated by determining the levels of selected trace metals in river water, river sediments, channel margin sediments and overbank soils. Samples were taken at five sites within an area of the Churnet Valley in Staffordshire, where the River Churnet flows through the two works. Analysis of river water samples by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) has shown that only copper is present above background levels considered to typify uncontaminated rivers. Analysis of river sediments, channel margin sediments and overbank soils by nitric-perchloric acid digestion and Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES) analysis has indicated contamination by arsenic, cadmium and copper in the vicinity of both works. Arsenic and copper are deposited primarily within the aquatic environment, although some contamination of the terrestrial environment by copper is also observed. Cadmium is deposited primarily within the terrestrial environment. The deposition of arsenic and copper in river and channel margin sediments respectively is also related to current and historical contamination.

Preliminary field studies were carried out at Dolfrwynog Bog in July 2000. Replicate samples of water, Armeria maritima plants and the soils adhering to its roots were collected and analysed for copper. Concentrations of up to 6486 mg kg−1 of copper in the soils were recorded. Accumulation of copper by the plant as expressed by concentration factors (CF) show that it is acting mainly as a copper excluder. Of the copper that is taken up, most of it is retained within the roots with very little being transported to the shoots of the plant. Moreover, a further possible mechanism of tolerance is exhibited by the excretion of copper through its decaying leaves. Towards the use of in vitro cultures to study the copper tolerance mechanisms in A. maritima a micropropagation protocol has been developed. The ex vitro plants have been rooted and established in compost.

River Yamuna, like most of the major rivers of India, has become increasingly polluted over the years from both point and non-point sources, particularly in the urban sectors such as Delhi. Field studies, conducted in January, 1994 have investigated the impact of wastewater discharges from four major drains (Najafgarh, Power House, Barapula, Kalkaji) on the overbanks, floodplains and Eichhornia in River Yamuna in Delhi, with particular reference to elemental contamination. It is concluded that except for Cd and Co, overall mean soil concentrations along the full stretch of the river in Delhi are within the world background levels of uncontaminated soils. However, the wastewater discharges from the drains, with the exception of Barapula drain, generally increase the elemental concentrations of overbank soils downstream of the discharges. Eichhornia plants growing along the banks receiving wastewaters from the Najafgarh and Barapula drains are unhealthy and reduced in population which can be attributed to a combination of alkaline pH of the growth medium, metal toxicity and high BOD at the site receiving effluents from the Najafgarh drain, and alkaline pH, metal toxicity and the turbid conditions of water with fly ash particle deposition on the plant surfaces at the site receiving effluents from the Barapula drain. Generally, considering the entire stretch of the river in Delhi, the roots of these plants growing on the overbank soils are found to be accumulators of all elements except Co, Al and Fe, with Co uptake being minimal. There are marked differences in elemental uptake of the water hyacinths growing on the overbanks and floodplains of the river.

The main solid waste product from coal-fired power stations is pulverised fuel ash (PFA), which can be enriched in toxic elements. Disposal of PFA by dry (in landfills) or wet (by slurrying) disposal methods can release these elements into the environment. Thereafter, the contaminants can be taken up by biota such as Eichhornia crassipes, a common aquatic plant, which has the ability to accumulate elements from water. This study investigates the uptake of Cd, Cu, Ni and Zn by E. crassipes grown in leachates and slurries prepared from two different PFA samples. PFA samples were obtained from Indraprastha Power Station (IPP Stn.) in New Delhi, India and the Ratcliffe-on-Soar Power Station in the UK. E. crassipes grown in PFA leachates and slurries at 1:5 and 1:50 solid:liquid (PFA:deionised water) ratios show that the plant has a very high accumulation capacity for Cd, Cu, Ni and Zn from both leachates and slurries and the uptake of these metals is stronger in the roots than in the tops of the plant. Metal accumulation, as shown by the accumulation factor (AF) values, is higher from both leachates and slurries for plants grown in the 1:50 (PFA:DIW) ratios than in the 1:5 ratios, initial metal concentrations being higher in the 1:5 ratios than in the 1:50 ratios. Lower metal accumulation in the plants grown in slurries than in leachates is related to the high turbidity of growth medium in slurries resulting in ash particles adhering to the root surfaces thus reducing the surface area of metal absorption. Eichhornia plants are able to reduce the pH of all leachates, especially the highly alkaline Ratcliffe leachates to near neutral conditions. Accumulation of Cd and Zn by the plant is higher from the lower pH IPP leachates than the Ratcliffe leachates, indicating that these metals are more soluble and bioavailable in the acidic medium. However, accumulation of Cu and Ni is independent of the pH of the leachates, indicating that other factors, such as metal species, presence of complexing agents in the growth solutions, and effects of competing metal ions may be contributory factors towards the metal uptake and accumulation by the plant.

Indraprastha Power Station (IPP Stn) and Rajghat Power House (RPH), owned by Delhi Electric Supply Undertaking, are both coal-fired power stations located on Ring Road in New Delhi. Ash content of the coal used ranges between 38–47%. The ash is collected in electrostatic precipitators which have an efficiency of 99.3% (IPP station), and 99.7% (RPH). There are instances of major dust pollution around the power stations from fly ash dispersal. The main method of disposal of fly ash from the power stations is by mixing with water, the resultant slurry is pumped through pipes to ash disposal ponds. The supernatant from these ponds is discharged into River Yamuna. Field studies have revealed large quantities of fly ash being deposited into the river. Local populations of Eichhornia crassipes have reduced dramatically between 1987–1995, with a marked reduction in the year 1994–1995. Field studies, conducted in January, 1995 have investigated the impact of fly ash dispersal in the Delhi region with particular reference to metal contamination. Elemental concentrations for a range of elements are determined by ICP-AES in fly ash and top soils along four transects from the power stations up to a distance of 8 km. The effects of fly ash leachates from the ash settling ponds on the river are determined by analyzing river overbank soils and vegetation for their elemental contents. It is concluded that fly ash dispersal from the stacks are a source of alkali, alkaline-earth and to some extent heavy metals in soils in the vicinity of the power stations, and enrichment of elements in river overbank soils are a result of discharge of fly ash leachates from ash disposal ponds. However, the impact from both these sources of metal contamination is not large enough to give cause for concern. Marked reduction in populations of Eichhornia crassipes downstream of the river where it receives leachates from the ash disposal ponds are attributed to turbidity of the ash pond leachates and metal toxicity. Elemental enrichment in the floodplain soils, as a result of fly ash particle deposition during monsoons, may enhance the horticultural value of these soils as is shown by a healthy cultivated crop of Brassica juncea.

In the context used by most consumers, tea is a beverage consisting of an infusion of processed and dried tea leaves. Human exposure to trace elements from tea consumption depends upon the trace element content of commercially produced teas, the transfer of these elements into the tea infusion, and the bioavailability of the elements in the human system. The transfer of trace elements into a tea infusion can be highly variable. As tea is a source of both essential and toxic elements, the intake of tea in the human diet can be beneficial or harmful. Bioavailability studies have shown that tea can be a useful source of some essential elements in the human diet and that moderate amounts of tea consumption is unlikely to have any harmful effect on healthy individuals. However, excessive consumption of tea can result in a person exceeding the allowable elemental intake for some elements.

The objective of this study was to evaluate the awareness and assessment of lung cancer risk factors with respect to sociodemographic factors among residents of Pokhara Valley, Nepal.A cross sectional study was carried out in 240 residents between 01 September 2009 and 31 March 2010 using a structured questionnaire containing details of lung cancer risk factors viz., smoking, environmental pollution, insecticide exposure, hereditary factors, protective diet and socio demographic details. Descriptive statistics and testing of hypothesis were used for the analysis using EPI INFO and SPSS 16 software.In the 240 subjects, the mean age was 33.4 ± SD 11.4 years, with a slight male preponderance in gender distribution (57.5% males vs. 42.5% females). 32.5% out of the study population were smokers (43.5% of males and 17.6% of females). Relationships could be established between gender and smoking (p=0.001, odds ratio=3.58), stoppage or restriction of tobacco use (p=0.001), smoking by mother during subjects' childhood as a motivation to develop smoking habit (p= 0.001), tobacco use as a cause of cancer (p=0.001), cancer as the most dreaded disease (p=0.009). Positive relationships were found between educational level and risk factors viz. smoking by mother during subjects' childhood (p= 0.03), wood or coal exposure causing lung cancer (p=0.0001), protection from lung cancer by consumption of green and yellow vegetables (p=0.0001) and insecticide exposure as a cause of lung cancer (p=0.0001). No strong relationship could be established between gender and outdoor pollution (p=0.721), insecticide exposure (p=0.219), protective diet (p=0.979) and hereditary factors (p=0.273).Awareness of lung cancer by tobacco use and other risk factors varied with socioeconomic status amongst residents of Pokhara. Despite their awareness of smoking as a risk factor for lung cancer, most of them still continue to smoke. Government and NGOs should gear up a population based counselling programme in this community.

A three-day pretreatment of olive somatic embryos (SE) with 0.75 M sucrose, combined with cryoprotection (0.5 M DMSO, 1 M sucrose, 0.5 M glycerol and 0.009 M proline) and controlled rate cooling, supported regrowth (as 34.6% fresh weight gain) and resumption of embryo development after cryopreservation. Pretreatment with mannitol or sorbitol did not support regrowth. Profiles of sugars, proline, antioxidant enzymes, Reactive oxygen species (ROS), secondary oxidation products and ethylene were constructed for the most successful (0.75 M) pretreatment series. Sucrose was the optimal pretreatment for supporting recovery, it also elevated glutathione reductase (GR) activity compared to controls, whereas superoxide dismutase (SOD), catalase and guaiacol peroxidase activities remained relatively unchanged. Superoxide dismutase activity was higher in SE pretreated with sucrose, compared with those pretreated with polyols; H2O2 was enhanced in SE pretreated with sorbitol and sucrose compared to mannitol. The overall trend for ethylene and OH production revealed their levels were highest in SE pretreated with polyols albeit, for individual treatments this was not always the case. Generally, pretreatments did not significantly change embryo secondary oxidation profiles of T hio B arbituric A cid R eactive S ubstances (TBARS) and Schiff's bases. In combination these studies suggest oxidative processes may influence regrowth of cryopreserved olive SE and that optimal pretreatments could, in part, increase tolerance by an overall enhancement of endogenous antioxidants (particularly GR), proline and sugars.

Bacteria from two areas in Wales have been extracted and partially identified. The areas are a copper impregnated bog in the Coed-Y-Brenin Forest with low pH and high carbon and copper content, and the Morfa Harlech salt marshes which have neutral pH and lower copper and carbon. Bacillus spp. was the predominant bacterium in both soils, but there was increased diversity of bacteria in the salt marsh soils. Bacteria from the Cu-rich, Coed-Y-Brenin soils showed higher growth densities in nutrient agar plates containing 10, 30 and 100 μg cm−3 Cu than bacteria from the salt marsh soils, indicating that bacteria from the Coed-Y-Brenin soils could tolerate higher copper concentrations. Pseudomonas spp. from both study areas grew better in media with added Cu at low levels. The possibility is discussed that the bacteria play a part in the bioavailability of Cu particularly in the copper-rich Coed-Y-Brenin area.

Endemic goitre was prevalent in the population of Derbyshire in the UK for many centuries until it declined from the 1930s. A contemporary medical survey showed that endemicity of goitre was particularly higher in the Carboniferous limestone areas of the Derbyshire-Peak District. Unlike classical goitrous areas of the world, where the distribution of goitre has been found to be related to the iodine content in the environment, there is no such relationship reported for the Derbyshire-Peak District area. The present study reviews the presence of endemic goitre in this area with reference to iodine in different environmental media using past and present data. In comparison with the world average values, the iodine contents in the soil and sediment in the Peak District are not deficient, but compared to England, Wales and Scotland averages, these levels are low. As no information on the mobility and bioavailability of iodine of this area is available, a cautious approach is necessary before any assumption is made on the aetiology of endemic goitre. The study also discusses some hypotheses relating to the possible cause of endemic goitre in the limestone areas. Further research needs are suggested depending on the land use and geochemistry of the Peak District to determine the underlying causes of the former endemic goitre in this area.