Raimondas Leopoldas Idzelis

Accumulation of heavy metals (Cu, Zn, Ni, Cr, Pb, Cd) in tissues of perch (Perca fluviatilis L.) and roach Rutilus rutilus (L.) under experimental conditions

Santrauka Ivertintas sunkiuju metalu pasiskirstymas gelavandeniu žuvu audiniuose monitoringiniuose vandens telkiniuose, taip pat ir kuoju bei eseriu, paveiktu sunkiuju metalu didžiausiomis leidžiamosiomis koncentracijomis (DLK), audiniuose. Eksperimentiniai tyrimai atlikti su Cu, Zn, Ni, Cr, Pb, Cd, kuriu kiekvienas pasižymi kancerogeniniu mutageni‐niu poveikiu. Nustatyta, kad svino DLK (0,2 mg/kg) buvo virsyta eseriu raumenyse 1,6 karto, o kuoju ‐ 1,4 karto. Kadmio DLK (0,05 mg/kg) eseriu ir kuoju raumenyse buvo virsyta apie 1,2 karto. Taip pat nustatyta, kad eseriai sunkiuosius metalus kaupia intensyviau nei kuojos. Eksperimentiniai duomenys sutampa su sunkiuju metalu tyrimu monitoringiniuose vandens telkiniuose duomenimis. Žuvu audiniuose Pb ir Cd koncentracijos yra didžiausios ir dažnai virsija Lietuvos higienos normoje nurodytaja DLK. Tokie rezultatai ipareigoja nuolat kontroliuoti sunkiuju metalu kieki žuvyse. Rezultatai pateikiami sunkiuju metalu sklaidos pasiskirstymo grafikuose.

Radiological investigation of meat of game and dose estimation for hunters and members of their families

Abstract The paper describes dose estimation for hunters and members of their families due to radionuclides 90Sr and 137Cs in meat of game hunted in Lithuania during two hunting seasons: 2003–2004 and 2004–2005. Research in the Nordic countries showed higher activity concentrations of both radionuclides in meat of game and higher doses to public consuming this meat. The scope of this investigation is radiological measurements of meat samples of game and dose estimation for hunters and members of their families. Measurements show that activity concentrations of 90Sr in samples of meat of game are less than for 137Cs. An average activity concentration of 90Sr in all the samples of meat of game analysed was 0,06±0,03 Bq/kg, for 137Cs – 7,8±4,6 Bq/kg. The highest activity concentration of 137Cs was measured in the sample of meat of moose from Matuiza forest near Varena district, and it was 30,8±2,0 Bq/kg. It was estimated that an annual effective dose due to 90Sr in meat of game was in the range from 5,6·10–1...

Experimental investigation of heavy metal accumulation in tissues of stone loach noemacheilus barbatulus (L.) and rainbow trout oncorhynchus mykiss (walbaum) exposed to a model mixture (Cu, Zn, Ni, Cr, Pb, Cd)

Abstract During experiment, fish were exposed to a heavy metal model mixture (Cu, Zn, Ni, Cr, Pb, Cd) for 14 days. Heavy metal concentrations corresponded to Maximum Permitted Concentrations (MPC) in surface waters. The amount of heavy metals in fish tissues was determined using atomic absorption spectrophotometry (AAS). Though both investigated fish species accumulated heavy metals with similar general intensity, the stone loach did it in the sequence gills > liver > muscle, and the rainbow trout ‐ conversely: muscle > liver > gills. Ni concentration in the stone loach muscle made 0.607 mg/kg and Pb concentration was 0.21 mg/kg, whereas Cd concentration in the rainbow trout muscle reached 0.45 mg/kg and exceeded the MPC indicated in the Lithuanian hygiene standard. These results coincide with the data of the heavy metal research into fish species from natural water bodies. Pb and Cd concentrations in fish tissues are the highest and frequently exceed the MPC. These findings urge for the constant control ...

Investigation into the aerodynamic processes of air treatment using a plate-type biofilter

ABSTRACT The research conducted has involved a laboratory stand of a plate-type air treatment biofilter with a capillary system for humidifying packing material composed of polymer plates vertically arranged next to each other and producing a capillary effect of humidification. The pattern of arranging the plates has sufficiently large spaces (6 mm), and therefore the use of the plate-type structure decreases the aerodynamic resistance of the device. Slightly pressed slabs attached on both sides of the plates are made of heat-treated wood fibre, to increase the longevity of which, wood waste has been heat-treated in the steam explosion reactor under the pressure of 32 bars and a temperature of 235°C. This is the method for changing the molecular structure of wood, which stops the decay of wood fibre in a humid environment and thus increases the life span of biofilter plates. The research performed has disclosed that, under the application of the above introduced structure of the biofilter, the aerodynamic resistance of the biofilter reaches 1 ÷ 5 Pa when the rate of the air flow passing through the device makes 0.08 m/s. For evaluating the reliability of the obtained results, the theoretical model has been applied.

Accumulation of heavy metals in different body tissues of Gibel carp Carassius gibelio separately exposed to a model mixture (Cu, Zn, Ni, Cr, Pb, Cd) and nickel

AbstractHeavy metals (HMs) are common persistent pollutants of aquatic ecosystems, which have a property to migrate and accumulate in water organisms. Little information has been compiled on HM accumulation and the interactions between them in fish exposed to their mixtures at environmentally-relevant concentrations. The aim of the present study was to determine accumulation patterns of Cu, Zn, Ni, Cr, Pb and Cd in the muscle, gills and liver of Gibel carp after 14-day exposure to HM model mixture (HMMM) and to Ni separately, at concentrations corresponding to Lithuanian inland water standards (Cu-0.01; Zn-0.1; Ni-0.01; Cr-0.01; Pb-0.005; Cd-0.005 mg/l, respectively). Laboratory tests were conducted on adult Gibel carp under semi-static conditions. The amounts of HMs in the water and body tissues were determined using atomic absorption spectrophotometry (AAS). Heavy metal accumulation order in body tissues of Gibel carp was as follows: muscle > gills > liver. The highest amounts found were of Zn (15.2 mg ...

Radiological investigation of red fox (Vulpes vulpes) in Lithuania

Abstract The paper presents 40K and 137Cs activity concentrations in muscle, bones and liver of red fox (Vulpes vulpes) from eastern and northern Lithuania. The short description of the applied radiochemical method is given. Activity concentrations of 40K in muscle ranges between 46.06 ± 0.43 and 110.92 ± 4.5 Bq kg−1 (fw = fresh weight). Average content of radioactive Cs in muscle is on the level of 5.78 ± 0.29 Bq kg−1. No clear relationship observed among the radionuclide concentrations in liver. The analyzed test samples do not show elevated contamination levels when compared with results of bones of small animals (rodents or insectivorous mammals) determined previously, so no accumulation ofbone seeking isotopes on higher step of the trophic chain concluded.