The utility of electrocardiography and echocardiography in copper deficiency-induced cardiac damage in goats

Environmental Science and Pollution Research - Copper deficiency (CuD) is a common mineral disorder in ruminants, which causes histomorphological changes in the heart due to disturbances in...     

Filtration Properties of Nonwovens

Abstract

This paper presents the results and conclusions from experimental investigations concerning filtration properties of nonwovens. The needled nonwovens were made from polyester fibres (PTE) with average fibre diameter 12 µm and polypropylene fibres (PP) with average fibre diameter 32 μm. Nonwovens were produced out of each of those fibres or out of a mixture of polyester and polypropylene fibres. This paper also presents investigations of nonwoven fabric made of polypropylene fibres (PP) with average fibre diameter 2.6 μm, which was formed according to melt-blown technology. Oil mist, as challenge aerosol, was used to evaluate the performance of filter media at various aerosol velocities. The average oil mist test aerosol particle diameter was 0.3 μm. Filter penetration was measured at oil mist concentration 0.24 g/m³.     

Distribution and environmental impacts of some radionuclides in sedimentary rocks at Wadi Naseib area, southwest Sinai, Egypt

The present study examines the natural radioactivity in some sedimentary rocks and their associated environmental impacts at Wadi Naseib area. Exposure rate (ER), dose rate (DR), radium equivalent activity (Ra(eq)), external hazard index (H(ex)), internal hazard index (H(in)) and radioactivity level index (I(gamma)) were calculated. Wadi Naseib area is covered with sedimentary rocks of early to late Paleozoic age. These rocks are classified into two types: mineralized and non-mineralized sediments. The radiometric investigations revealed that uranium and thorium contents reached up to 710 and 520 ppm, respectively, in the mineralized rocks. This was attributed to the presence of some secondary uranium minerals. All sediments had low values of eTh and K content. The exposure and dose rates exceeded public permissible values in the mineralized sediments. Exposure and dose rates were within the safety range for workers and the public in the non-mineralized sediments. The expected environmental impacts may be low due to the limited occurrence of U-mineralization and corresponding areas for radiation exposure. Some precautions and recommendations were suggested to avoid any possible environmental impacts from areas and/or raw materials of high intensity of natural radiation sources.     

Partitioning of radiostrontium in marine aqueous suspensions: laboratory experiments and modeling studies

Quantitative information on the adsorption/desorption of radionuclides by suspended loads is important in the study of their environmental behavior. In this paper, controlled laboratory experiments were directed at studying the kinetic transfer and final distribution of radiostrontium in aqueous suspensions using 85Sr as tracer. The results showed that the uptake of 85Sr in seawater can be properly described by one reversible-reaction model. However, in the absence of competitive cations, it has been shown that two reactions of different characteristic times are unambiguously involved in the kinetic evolution of adsorption. Thus, a modeling approach consisting of three-box model has been applied. The model predicts in a satisfactory way the time evolution of activities in the dissolved phase and two sites in the particles. Experimental evidence showed, through comparison among kinetic and distribution coefficients corresponding to different conditions, that Ca2+ affects strongly the rate and extent of Sr uptake by suspended particles. On the other hand, distribution coefficients were found to be sensitive to changes in suspended particulate matter (SPM) concentration, exhibiting a reverse effect with this parameter on the adsorption. In addition, desorption from particles is important showing that Sr can be easily released due to cation-exchange processes.     

Gamma aminobutyric acid radioreceptor‐assay a possible biomarker for human exposure to certain agrochemicals

Abstract

Cyclodiene insecticides, hexachlorocyclohexanes, pyrethroids, bicyclophosphates, the bicycloorthocarboxylate insecticides and some of their metabolites and environmental degradation products are central nervous system toxicants with high specific binding affinity to the chloride channel of the γ‐ aminobutyric acid (GABA)_A receptor‐ionophore sites. [³⁵S] tertiary‐butylbicyclophosphorothionate (TBPS) with specific activity higher than 60 Ci/mmole has a high binding affinity to the same sites and is now commercially available and can be used to label the GABA_A receptor for the development of a radioreceptor assay technique. The GABA receptor was prepared by ultra centnfugation and dialysis of brain homogenates of either cow, goat, rat or catfish. The receptor was then labeled with [³⁵S] TBPS and the assay was conducted by measuring the displacement of radioactivity following incubation with samples containing the analytes. A radioreceptor assay protocol was developed to measure the amount of the α‐endosulfan in blood samples. The assay was extremely sensitive, and can detect 0.2 nM of endosulfan at a level equivalent to 0.08 ppb or 8x10^‐11 gm of endosulfan in each ml of the blood samples.     

Effects of two organophosphorus insecticides on some biochemical constituents in the nervous system and liver of rabbits

Abstract

Male Baladi rabbits were acutely and sub‐chronically intoxicated with cyanofenphos and profenophos. The levels of cholesterol, triglycerides, B‐lipoproteins and total proteins were determined in the serum, brain, spinal cord and sciatic nerve of rabbits. Moreover, the activities of alkaline phosphatase, acid phosphatase and glutamic‐pyruvic transaminase were determined in the liver of the animals. The whole Studie revealed that the biochemical constituents were highly affected by the tested insecticides. Also, the liver function suffered from adverse effects of the tested insecticides.     

Pb in medicinal plants from Jordan

This is the first report on Pb in medicinal herbs from Jordan. Medicinal herbs may present a health risk due to the presence of toxic metals. Seventy-nine dry medicinal plant samples were collected from herbalist shops in Jordan. The plants were digested with acids and analyzed for total Pb concentration using atomic absorption spectrometry. Mean Pb concentration was 15.9 μg/g on a dry weight basis. Our results show that Pb concentrations in Jordan medicinal plants are higher than published data in other countries. The highest level of 33.4 μg Pb/g was determined in Inula viscosa, and the lowest level of 3.0 μg Pb/g was found in Nigella sativa. Calculated daily intakes of Pb of most analyzed herbs were high; most of them are higher than recommended values by the world health organization (WHO). Fortunately, the herbs that contain the highest Pb levels are the less commonly used medicinal herbs in Jordan. The mean Pb levels in the most commonly, commonly and less commonly used herbs in Jordan are 13.9, 13.1 and 16.9 μg Pb/g, respectively. The average dietary intake of Pb through a mixture of these medicinal herbs consumption, assuming 5.0 g herbs is consumed daily, is 79.5 μg Pb/day, which is higher than the maximum daily limit allowed by WHO. We conclude that most of the medicinal plants consumed in Jordan contain significant amount of Pb, and therefore, people of Jordan should not consume large amounts of these herbs.     

Legislative aspects of pesticide regulations

Abstract

This paper reviews the development of pesticides as an agricultural and health tool and discusses the national and international implications of pesticide regulation. The need for scientific input to the legislative and regulative processes is explained. Appropriate legislation and regulatory structures are presented. Finally, the need for international cooperation in the use and control of pesticides is analyzed.     

Trace element content in tea brewed in traditional metallic and stainless steel teapots

The migration of metals in tea brewed in metallic teapots was investigated. The teapots were obtained from North Africa stores in Brussels in 2005–2006 and in 2011. Chinese gunpowder green tea, the most commonly used tea in the Moroccan community, was used to prepare the tea. Tea brewed in metallic teapots was compared to tea brewed in a glass vessel in order to evaluate the contribution of the tea and the teapots to the metal concentrations in the brewed tea. Tea samples were also collected in Moroccan households and in tearooms in Brussels. The elements As, Cd, Pb, Sn, Mn, Fe, Cr, Co, Ni, Cr, Cu, Zn, and Al were analyzed by high-resolution sector field inductively coupled mass spectrometry. The relationship between the metal composition of the alloy of the teapot and the metal concentration in tea was also investigated. Migration of Pb and to a lesser amount Ni, Cu, and Zn was observed in brass teapots and migration of Cd from a number of stainless steel teapots was observed. The soldering connecting the sprout to the teapot was shown to be an important source of Pb to the tea. High levels of Mn and Al were also observed in the brewed tea and these elements where shown to originate from the tea itself. Metal exposure from tea drinking was calculated for different tea consumption levels and different metal concentration levels and compared to toxicological reference values.