Influences of adding easily degradable organic waste on the minimization and humification of organic matter during straw composting

To find a better composting process with low greenhouse gas emission and high humus production, the effect of adding kitchen waste on reduction and humification of organic matter during straw composting was studied. Three processes were compared, consisting of different ratios of straw and kitchen waste (1:2, 1:1, and 2:1). At four time points over a 62-d incubation, the reduction and humification of compost was evaluated by measuring the total mass, carbon content, and humic material content of the compost. Treatment 1 (straw/kitchen waste ratio of 1:2) reduced the total mass of compost the most. Treatment 2 (straw/kitchen waste ratio of 1:1) reduced the total carbon content the most, reflecting the highest emission of greenhouse gas. Treatment 3 produced the most humic acid material and released the lowest amount of carbon. Hence, from the point of view of reducing greenhouse gas emissions and increasing stable organic matter such as humus and humic acid during composting, treatment #3 was optimal. The three treatments resulted in significant differences in microbial biomass and enzyme activity during composting. The highest amount of active microbial biomass was associated with the largest reduction in compost mass (treatment 1). Higher proportions of straw (treatments 2 and 3), which contains more lignin, were associated with greater β-glycosidase activity, which may generate more humus that can improve soil quality. Dehydrogenase activity seemed to be the most important microbial factor in organic carbon catabolism or humification.     

Clinical effects and cholinesterase activity changes in workers exposed to phorate (Thimet)

Abstract

Phorate (Thimet), an aliphatic derivative of phospnorus is a hignly toxic insecticide. In order to implement the safety measures, the clinical manifestations and cholinesterase (ChE) activity were evaluated before and after 2 weeks of exposure to this insecticide in 40 male tormulators.

The 2 week's exposure reveal signs and symptoms of toxicity in 60% of the formulators. Gastrointestinal symptoms and lowering of heart rate (bradycardia) were more prominent as compared to the neurological symptoms. A significant depression in plasma ChE activity was observed at the end of 1st week (55%) and 2nd week (71%) as compared to the respective pre‐exposure values. A recovery up to 79% of the pre‐exposure activity of this enzyme was noticed 10 days after cessation of the above exposure.     

Persistence and biodegradation of carbaryl in soils

Abstract

The persistence of the methylcarbamate pesticide carbaryl was studied in four soils under flooded conditions. A substantial portion of the pesticide was recovered from all soils even after 15 days of its application, with the recovery ranging from 37% in an alluvial soil to 73% in an acid sulfate soil. The degradation of carbaryl was more rapid under flooded conditions than under nonflooded conditions. A bacterium, Pseudomonas cepacia, isolated from a flooded soil amended with a related methylcarbamate pesticide carbofuran, degraded carbaryl in a mineral medium supplemented with yeast extract.     

Rotary Kiln Incineration III. An Indepth Study—Kiln Exit/Afterburner/Stack Train and Kiln Exit Pattern Factor Measurements During Liquid CCl4 Processing

Temperature and stable species concentration data are presented from various locations within a full-scale rotary kiln incinerator firing natural gas/carbon tetrachloride/air. The data are being collected as part of a cooperative program involving university, industry and government participation. The overall goal of the program is to develop a more sophisticated understanding of and a predictive capability for rotary kiln and afterburner performance as influenced by basic design and operational parameters. Non-uniformities in stable species and temperature exist for this particular kiln, at the kiln exit, under certain operating conditions. Flow perturbations from within the kiln were found to persist into the afterburner, but not into the stack. High destruction and removal efficiencies (DRE’s) were achieved under the operating conditions of these tests through adequate secondary combustion processing.     

Rotary Kiln Incineration IV. An Indepth Study— Kiln Exit,Transition and Afterburner Sampling During Liquid CCl4 Processing

Detailed temperature and stable species concentration data are presented from the kiln exit, transition section and afterburner of a full-scale incinerator facility firing natural gas/carbon tetrachloride/air. The data are collected as part of a cooperative program involving university, industry and government participation. The overall goal of the program is to develop an understanding and predictive capability for rotary kiln and afterburner performance as influenced by basic design and operational parameters. The data demonstrate that nonuniformities in stable species and temperature exist, under certain operating conditions, at the kiln exit in the vertical direction only. Measurements from the transition section indicate that non-uniformities may exist within this region under certain operating conditions. Flow perturbations from within the kiln can persist into the afterburner, although the degree of nonuniformity is substantially reduced compared to either the kiln or transition sections. High destruction and removal efficiencies were achieved under all operating conditions of these tests through a combination of kiln and secondary combustion processing.     

Development of Cleanup Standards at Superfund Sites: An Evaluation of Consistency

The Washington Department of Ecology (WDOE) recently developed a regulatory program for determining cleanup standards at hazardous waste sites. One of WDOE's first tasks in the development of a cleanup standards program was to evaluate how standards have been developed and implemented under Superfund.

The evaluation of cleanup standards revealed: (1) a great deal of variation among sites, both in the magnitude of the standards set for some contaminants and the basis on which they were set, and (2) that there is no consistent decision-making approach for determining how standards should be set. This lack of consistency and guidance has the potential to result in overly stringent or underprotective cleanup requirements and inefficient standard development.

Washington State has adopted an approach that allows for implementing uniform numerical cleanup standards at relatively straightforward sites and provides a process for establishing site-specific cleanup levels at more complex sites. This approach is expected to facilitate development of standards that offer appropriate human health and ecological protection while minimizing private and public sector site management and cleanup costs.     

Determination of Volatile Organic Compounds in the Atmosphere Using Two Complementary Analysis Techniques

ABSTRACT

During a preliminary field campaign of volatile organic compound (VOC) measurements carried out in an urban area, two complementary analysis techniques were applied to establish the technical and scientific bases for a strategy to monitor and control VOCs and photochemical oxidants in the Autonomous Community of the Basque Country. Integrated sampling was conducted using Tenax sorbent tubes and laboratory analysis by gas chromatography, and grab sampling and in situ analysis also were conducted using a portable gas chromatograph. With the first technique, monocyclic aromatic hydrocarbons appeared as the compounds with the higher mean concentrations. The second technique allowed the systematic analysis of eight chlorinated and aromatic hydrocarbons. Results of comparing both techniques, as well as the additional information obtained with the second technique, are included.     

Characterization of Municipal Solid Waste Incineration Residues From Facilities with Different Air Pollution Control Systems

Abstract

Municipal Solid Waste incinerator residues produced in two types of facilities were exhaustively characterized: granulometry, mineralogy, chemical composition, leaching behavior, and elemental distribution as a function of particle size. Air Pollution Control (APC) residues coming from a semi-dry scrubber have shown higher solubility than fly ashes originating in an Electrostatic Precipitator (ESP), as well as higher contents in volatile metals (Cd, Hg). Different metal speciation and distribution as a function of particle size have been found in fly ashes (ESP residues) and APC residues. In APC residues, heavy metals (with the exception of Hg) show a parabolic distribution with maxima in the smallest and largest particles, following the same profile as soluble salts. Metal distribution for APC residues exhibits that metals generally are not associated with silicate aluminate matrix. Results show the effect of adding lime to APC residues in metal speciation and distribution.     

High-affinity ouabain receptors: primary membrane sensors for ionizing radiation

Although the high sensitivity of the Na/K pump in cell membrane to ionizing radiation is well known in literature, the individual role of different isoforms of pump in determination of its radio-sensitivity is not clear yet. This is the subject of the present investigation. Using isotope, electro-physiological and enzymological methods, the effect of γ-ionizing radiation on cell membrane voltage-current characteristics, acetylcholine-induced membrane current, ²²Na⁺ and ⁴⁵Ca²⁺ exchange between cells and bathing solution, Na+K⁺-ATPase activity, dose-dependent ouabain binding with cell membrane, intracellular cAMP and membrane phosphorylation in snail neurons were studied. The changes in neurons as a result of 30-min γ-radiation exposure of snails to 5.16 Ci/kg at the end of the first 30 min of post-radiation period were as follows: the increase in membrane ionic conductance reversed the ouabain sensitivity of acetylcholine-induced currents, stimulation of ²²Na⁺ and ⁴⁵Ca²⁺ uptakes, inhibition of Na/K pump, activation Na/Ca exchange in reversed mode, increase in ouabain binding with high-affinity α₃ and decrease with α₂ middle-affinity receptors, decrease in intracellular cAMP content and membrane dephosphorylation. On the basis of the obtained data, it is suggested that both α₃ and α₂ catalytic subunits of Na⁺+K⁺-ATPase serve primary membrane sensors through the activation of which the biological effect of γ-radiation on neurons is realized. The IR has activation effects on α₃-dependent Na⁺/Ca²⁺ exchange in forward and its inactivation on α₂-dependent reverse modes.