Biomagnification of naturally-produced methoxylated polybrominated diphenyl ethers (MeO-PBDEs) in harbour seals and harbour porpoises from the Southern North Sea

Harbour seals and harbour porpoises are top predator species from the North Sea, have long life spans and hence, are known to accumulate high levels of anthropogenic contaminants. To gain knowledge about the behaviour of naturally-produced compounds in these marine mammals, the biomagnification of naturally-produced methoxylated polybrominated diphenyl ethers (MeO-PBDEs) was assessed. The biomagnification of MeO-PBDEs (2′-MeO-BDE 68 and 6-MeO-BDE 47) was lower in harbour seals (all biomagnification factors (BMFs) < 1) compared to the same age–gender groups of the harbour porpoises (all BMFs > 1). This may indicate a better metabolic breakdown of MeO-PBDEs in harbour seals, as was previously suggested for polybrominated diphenyl ethers (PBDEs). In both predators, 6-MeO-BDE 47 had the highest concentrations (range: 45–483 ng/g lw and 2–38 ng/g lw for harbour porpoises and seals, respectively) compared to 2′-MeO-BDE 68 (range: 2–28 ng/g lw and 1–6 ng/g lw for harbour porpoises and seals, respectively). In general, the highest concentrations were found in juveniles, suggesting an increased biotransformation capacity with age or the influence of dilution by growth for both species. Here we show that naturally-produced brominated organic compounds can biomagnify and accumulate in North Sea top predators, although to a lesser extent than anthropogenic lipophilic contaminants, such as polychlorinated biphenyls (PCBs) or PBDEs.     

Utilisation of bubble resonance phenomena to improve gas–liquid contact

 In several branches of science and technology a gaseous phase is dispersed into a liquid in the form of bubbles, a gaseous component then dissolves into the liquid and subsequently undergoes chemical reaction. The overall process performance can be improved substantially when the area of gas–liquid contact is increased. By subjecting the liquid phase to low frequency vibrations, the bubbles are shown to suffer significant breakage, induced by resonance. When the vibration is properly tuned, the interfacial area is found to increase by a factor of 1.8–2.4, depending on the properties of the liquid. Resonance-induced bubble breakage phenomena have a great potential for improving the rates of chemical processes involving fast reactions, with minimal energy input. Received: 7 July 2000 / Accepted in revised form: 28 August 2000     

The annual reproductive cycles of Uca annulipes,Portunus pelagicus and Metapenaeus affinis (Decapoda: Crustacea) from the South-west coast of India

Employing the gonad index method, the reproductive cycles of three decapod crustaceans, Uca annulipes (Latreille), Portunus pelagicus (Linnaeus) and Metapenaeus affinis (Milne-Edwards) have been studied. In these crustaceans breeding is not continuous all the year round, but extends over several months of the year with distinct peak periods of gonadal activity. The male and female reproductive cycles are not concurrent. The peak of the reproductive cycle of males occurs slightly earlier in the breeding season than that of females. These studies indicate the possibility of production of successive broods of eggs during the same breeding season. In these species, the low saline conditions of the monsoon period are unfavourable for breeding. The medium and high saline conditions during the post-monsoon and pre-monsoon months, respectively, with plenty of planktonic food for the larvae, seem to be the favourable periods for breeding activity.     

Transport of metanil yellow in the rat plasma and interaction of its metabolite,p‐aminodiphenylamine with serum proteins

Binding affinity of metanil yellow and its breakdown product p‐aminodiphenylamine to serum proteins has been studied employing chromatographic separation on Sephadex G‐200 and by paper and polyacrylamide gel electrophoresis. Metanil yellow has more affinity towards albumin than to globulins. The complexing is presumably through electrostatic forces. p‐Aminodiphenylamine on the other hand, preferably binds to globulin fractions of serum protein. However, a stable binding with BSA alone was also observed. The binding was quite stable and was accompanied by a shift in absorbance from 430 nm to 500 nm. Aspartic acid moiety of protein was found to be one of the units involved in the binding of p‐ADPA to proteins.     

Hematological and biochemical alterations in sprayers occupationally exposed to mixture of pesticides at a mango plantation in Lucknow,India

The aim of this study was to examine the hematological and cholinesterase (ChE) activity levels of pesticide sprayers employed in mango plantations at Lucknow. Fifty-two sprayers from mango plantations who regularly spray mixtures of pesticides including organochlorines (OC), organophosphates (OP), and carbamates were included as exposed group. Twenty residents living close to mango plantations, but not involved in pesticide spraying were taken as controls. Pesticide residues for OC were analyzed in blood by gas chromatography with electron capture detector. There was a significant decrease in acetylcholinesterase and butyrylcholinesterase activities in pesticide sprayers (n?=?52) relative to the control group (n?=?20). A significant difference in the frequency distribution of hematological variations in red blood cell, white blood cell, monocytes, neutrophils, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, and platelet count was observed. Residues of OC pesticides including α-hexachlorocyclohexane (HCH) and total HCH were found to be significantly higher in the blood of sprayers compared to controls. Hematological variations were quantitatively more frequent among the sprayers with 5 years of pesticide exposure compared to the controls and to subjects with less than 5 years of exposure group. Hematological abnormalities in sprayers were correlated with pesticide exposure as evidenced by lower ChE activity as well as the presence of OC pesticides in blood. The poorly controlled use of pesticides in the plantation appeared to have produced sub-clinical intoxication in the sprayers and indicated the need for training and implementation of proper, safer hygiene practices.     

Soil contamination of heavy metals in the Katedan Industrial Development Area, Hyderabad, India

Studies on quantitative soil contamination due to heavy metals were carried out in Katedan Industrial Development Area (KIDA), south of Hyderabad, Andhra Pradesh, India under the Indo-Norwegian Institutional Cooperation Programme. The study area falls under a semi-arid type of climate and consists of granites and pegmatite of igneous origin belonging to the Archaean age. There are about 300 industries dealing with dyeing, edible oil production, battery manufacturing, metal plating, chemicals, etc. Most of the industries discharge their untreated effluents either on open land or into ditches. Solid waste from industries is randomly dumped along roads and open grounds. Soil samples were collected throughout the industrial area and from downstream residential areas and were analysed by X-ray Fluorescence Spectrometer for fourteen trace metals and ten major oxides. The analytical data shows very high concentrations of lead, chromium, nickel, zinc, arsenic and cadmium through out the industrial area. The random dumping of hazardous waste in the industrial area could be the main cause of the soil contamination spreading by rainwater and wind. In the residential areas the local dumping is expected to be the main source as it is difficult to foresee that rain and wind can transport the contaminants from the industrial area. If emission to air by the smokestacks is significant, this may contribute to considerable spreading of contaminants like As, Cd and Pb throughout the area. A comparison of the results with the Canadian Soil Quality Guidelines (SQGL) show that most of the industrial area is heavily contaminated by As, Pb and Zn and local areas by Cr, Cu and Ni. The residential area is also contaminated by As and some small areas by Cr, Cu, Pb and Zn. The Cd contamination is detected over large area but it is not exceeding the SQGL value. Natural background values of As and Cr exceed the SQGL values and contribute significantly to the contamination in the residential area. However, the availability is considerably less than anthropogenic contaminants and must therefore be assessed differently. The pre- and post-monsoon sampling over two hydrological cycles in 2002 and 2003 indicate that the As, Cd and Pb contaminants are more mobile and may expect to reach the groundwater. The other contaminants seem to be much more stable. The contamination is especially serious in the industrial area as it is housing a large permanent residing population. The study not only aims at determining the natural background levels of trace elements as a guide for future pollution monitoring but also focuses on the pollution vulnerability of the watershed. A plan of action for remediation is recommended.     

Constitutive model for municipal solid waste incorporating mechanical creep and biodegradation-induced compression

A constitutive model is proposed to describe the stress–strain behavior of municipal solid waste (MSW) under loading using the critical state soil mechanics framework. The modified cam clay model is extended to incorporate the effects of mechanical creep and time dependent biodegradation to calculate total compression under loading. Model parameters are evaluated based on one-dimensional compression and triaxial consolidated undrained test series conducted on three types of MSW: (a) fresh MSW obtained from working phase of a landfill, (b) landfilled waste retrieved from a landfill after 1.5 years of degradation, and (c) synthetic MSW with controlled composition. The model captures the stress–strain and pore water pressure response of these three types of MSW adequately. The model is useful for assessing the deformation and stability of landfills and any post-closure development structures located on landfills.     

Static and Dynamic Behavior of Fibrous Polymeric Composite Materials at Different Environmental Conditions

The study of static and dynamic behavior of environmentally conditioned fibre reinforced polymeric (FRP) composites is necessary and crucial to examine the durability, reliability and sustainability of these noble materials. FRP composites are being used all around the globe and substituting the conventional materials, starting from mini toys to large aerospace components. Present review has introduced to accumulate and understand the disseminate literature in concentrating the significance of understanding the static and dynamic behavior of FRPs with changing environmental conditionings (hygrothermal, low and high temperature, salt solution, freeze thaw, UV light) and with the interaction of different nano-fillers. Their stability and integrity in diverse service environments may be reformed by their reactions against different nature of loadings i.e. static or dynamic and the components such as fibre, matrix and fibre/matrix interfaces in those environments. The static and dynamic states of loading may come with a possible weaker region to encounter the durability and integrity of the composites. To understand the exact failure modes that correlates the position of environmentally conditioned interfaces and dynamic state of loadings, thus confusing the estimation of its overall performance and mechanical behavior. Interface reliability and durability is vital since in-service environments the degradation in the interfacial region leads to complete composite failure. Therefore, the study of combined effects of various in-service environmental conditions and the role of static and dynamic behavior on the interface will be a crucial part related to the multiaxial dynamic states of failures occurring in FRP’s.     

Geographic information systems (GIS) based model of dairy manure transportation and application with environmental quality consideration

Survey information was used to develop a minimum cost spatial dairy manure transportation model where environmental quality and crop nutrient requirements were treated as constraints. The GIS model incorporated land use types, exact locations of dairy farms and farmlands, road networks, and distances from each dairy farm to receiving farmlands to identify dairy manure transportation routes that minimized costs relative to environmental and other constraints. Our analyses indicated that the characteristics of dairy manure, its bulk and relatively low primary N, P₂O₅ and K₂O nutrient levels limit the distribution areas or distances between the farms and the land over which the manure can be economically spread. Physical properties of the land limit the quantities of nutrients that can be applied because of excess nutrient buildup in soil and potential to harm nearby waterbodies and downstream people and places. Longer distances between dairy and farmland favor the use of commercial fertilizers due to the high cost of manure transportation. At $0.08 per ton per km transportation cost, the optimal cut-off distances for dairy manure application is 30 km for N and 15 km each for P₂O₅ and K₂O consistent rules. An analysis of dairy manure application to different crop types suggest that, on average, 1 ha of land requires 61 tons of dairy manure to meet the recommended N, P₂O₅ and K₂O needs.     

Two‐dimensional transport of lactate‐modified nanoscale iron particles in porous media

This study investigates the two‐dimensional transport of nanoscale iron particles (NIP) and lactate‐modified NIP (LMNIP) in homogeneous and heterogeneous porous media under typical pressurized groundwater flow conditions. A two‐dimensional bench‐scale test setup was developed and a series of experiments was conducted simulating homogeneous sand profile and two‐layer profile with two different sands. NIP and LMNIP at a concentration of 4 g/L were prepared in electrolyte simulating groundwater conditions and were injected at the inlet of the test setup under different pressure gradients (0.5. 0.8, 1, and 2 pounds per square inch). During the testing, effluent was collected and its volume and nanoiron concentrations were measured. At the end of the testing, soil cores were obtained at different distances from the inlet and were used to measure nanoiron concentrations and magnetic susceptibility values. Results showed that the transport of NIP and LMNIP was enhanced by increased pressure gradient. LMNIP transport occurred more uniformly as compared to bare NIP. The iron concentrations decreased with distance from the inlet to the outlet and increased from the top to the bottom of the test cell. The data indicate that, as the particles were transported, they underwent aggregation and sedimentation, which resulted in the observed non‐uniform spatial distribution of iron. The NIP and LMNIP transported through the high‐porosity and high‐permeability soil layer in the heterogeneous soil profile, implying that the transport occurred predominantly along the path of least resistance for the flow. Magnetic susceptibility values are found to have good correlation with the iron content in the soil and are helpful to characterize the transport of NIP and LMNIP. Overall, this study shows that the non‐uniform distribution of NIP and LMNIP occurs under two‐dimensional transport conditions and the soil heterogeneities can significantly impact the transport of NIP and LMNIP. The design of field delivery systems should consider such conditions and optimize the pressurized injection systems. © 2011 Wiley Periodicals, Inc.