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PubMed1990

[Hydrolysis of waste keratin material for use of certain sulfonated acids. I. Chemical characteristics of protein waste products].

We have fixed optimal conditions for preparation to analysis of waste keratin material (bristle, cerebellum and hoof), which then description of the chemical character define in there fat, moisture and ash content, nitrogen: total and ammonium and qualitative and quantitative composition amino acids. Results, which we obtained indicate to possibility utilization waste keratin material to obtain of full value, dyeability protein products.

Amino Acids↗
PubMed2004

Dogmas and controversies in the handling of nitrogenous wastes: the effect of feeding and fasting on the excretion of ammonia, urea and other nitrogenous waste products in rainbow trout.

Ammonia and urea are the primary forms of nitrogen excretion in teleost fish. There exists, however, a discrepancy between the sum of ammonia plus urea nitrogen and total nitrogen, indicating that 'unknown' nitrogen end products may play an important role in nitrogen metabolism. The current study analysed a wide range of nitrogen end products in both fed and fasted juvenile rainbow trout. Ammonia-N (53-68%) and urea-N (6-10%) were confirmed as the most important forms of nitrogenous waste, but an interesting finding was the considerable excretion of nitrogen as amino acids (4-10%), via the gills, and as protein (3-11%), probably via the body mucus. Use of anal sutures delineated an important role for the gastrointestinal tract in the production of ammonia-N and urea-N in fed fish, but amino acid-N and protein-N output by this route were both negligible. Alternative nitrogen products - trimethylamine, trimethylamine oxide, uric acid, and nitrite + nitrate - were not excreted in detectable quantities. Creatine-N and creatinine-N outputs were detected but contributed only a small fraction to total nitrogen excretion (<1.4%). Despite the wide scope of nitrogenous end products investigated, a considerable proportion (12-20%) of nitrogen excretion remains unknown. Possible alternative end products and methodological considerations are proposed to explain this phenomenon. The findings described above were used to recalculate the nitrogen quotient (NQ=(N)/(O(2))) on trout that had been either fasted or fed various daily rations (1%, 3% or 5% dry food per unit wet body mass per day). Feeding increased oxygen consumption ((O(2))) and total-N excretion ((N)). The NQ is often used as a measure of protein utilisation in aerobic metabolism and assumes that all protein (and amino acid) fuels are converted by oxidation to nitrogenous waste products that are excreted. However, the results showed that calculation of the NQ based on total nitrogen excretion may overestimate protein utilisation in aerobic metabolism because of significant excretion of N in the form of proteins and amino acids, whereas the use of summed ammonia-N and urea-N excretion probably underestimates the contribution of protein towards aerobic metabolism. These errors increase as ration increases, because the discrepancy between total-N excretion and ammonia-N + urea-N excretion increases.

Amino Acids↗
PubMed2005

The application of batch extraction tests for the characterisation of solidified ferro alloy waste products.

Leach testing is arguably the best indicator of the effectiveness of pre-landfill treatments, including solidification/stabilisation (S/S), in reducing mobility of waste constituents. The results of leach tests can, however, also be interpreted to provide an understanding of the mechanisms via which toxic species are retained in the S/S product. An understanding of retention mechanisms contributes to the development of improved waste treatment systems. In this paper, we explore the applicability of four extraction tests, Pore Solution Expressions, the TCLP, the Equilibrium Extraction (EE) and the Sequential Chemical Extraction (SCE) for providing a description of the mechanisms of containment within an S/S product. The waste materials explored here are ferrochrome dusts with high levels of metals including Cr and Zn. The errors in results from the pore solution expressions and sequential chemical extractions were too high to draw any quantitative conclusions, although some qualitative comments could be made. The latter observations, however, were consistent with those from the other two tests, and together these build a comprehensive picture of the S/S products. For these specific products, it is suggested that a small amount (approximately 1%) of the Cr is Cr(VI) which is readily mobile, approximately 5% is Cr(III) which is mobile under acidic conditions and the remainder is a stabile chromite which is not readily mobile. For Zn, however, roughly equal proportions are contained as a species (possibly Zn(OH)2) whose release is pH dependent, and as a stable, immobile species on the surface of the dust particles.

Chemistry Techniques, Analytical↗
PubMed1981

[Isolation of synthetic organic acids from the waste products of human vital activities in closed life-support systems].

Organic acids have been obtained in an alkaline medium from a mixture of monosaccharides-carbohydrates to be used in a closed life support system. Methods of analysis of mixtures of synthetic acids have been developed. The composition of mixtures of organic acids has been identified by paper chromatography. During electrodialysis the mixtures release calcium ions. The use of mixtures of synthetic organic acids as carbon source gives rise to an intensive growth of the yeast Candida tropicalis SK-4.

Acids↗
PubMed2001

Red mud of aluminium production waste as basic component of new construction materials.

The work presented here shows the possibility of using the red mud waste from the Bayer process used for aluminium production as the main component of new construction materials. It describes some recent experiments lasting 180 days as well as some 1 year old samples. The best part of materials used are industrial wastes, but some of them contain small (no more the 2%) additions of CaO or Portland Cement (PC) to increase the strengthening rate of the samples. The high strength values of these materials allow their use as new materials for road and airfields bases, levee core, dumps, foundations, etc. They can also be used to make bricks, tiles, and similar items. In addition to the economic factors, these materials are very easy to use and no new residues are generated. The results of the heavy metal leaching tests, not included in this paper, show very low levels of their leachability in acid solutions, far below the demands of the Spanish environmental standards. This can be explained by the strong chemical binding of heavy metals in practically insoluble chemical compositions.

Aluminum↗
PubMedDate not supplied

Toxicological investigations in the semiconductor industry: II. Studies on the subacute inhalation toxicity and genotoxicity of gaseous waste products from the aluminum plasma etching process.

Male and female Wistar rats were exposed to waste gas arising from a plasma etching process in the semiconductor industries for six hr per day, five days per week, for four weeks in order to characterize subacute organ toxicity and genotoxicity. The waste gas was a complex mixture of different chlorinated hydrocarbons, inorganic by-products, and unused process gases, diluted by room air. Neither death nor behavioral changes occurred after subacute exposure. No significant exposure-related effects on body weight gain, hematology, or cardiovascular parameters were observed. Only slight effects on organ weights and clinical chemistry were seen in the exposed animals. The exposed rats of both sexes showed statistically significant increases in chromosomal aberrations and sister chromatid exchanges in bone marrow cells.

Administration, Inhalation↗
PubMed2004

Effects of prolonged copper exposure in the marine gulf toadfish (Opsanus beta). I. Hydromineral balance and plasma nitrogenous waste products.

Acute (96 h) and prolonged (30 days) copper exposure induced osmoregulatory disturbance and impaired nitrogenous waste excretion in the marine teleost, the gulf toadfish (Opsanus beta), which was found to be extremely tolerant to acute copper exposure with a 96 h LC50 exceeding 340 microM but exhibited disturbed mineral balance in response to both acute and prolonged exposure to approximately 12 microM copper. The main cause of copper toxicity was found to be Na+ and Cl- regulatory failure leading to elevated plasma [Na+] and [Cl-] and osmolality which in turn led to fluid loss from muscle tissue. Analysis of intestinal fluid composition revealed a complicated pattern of effects of copper exposure. Intestinal transport physiology was directly influenced by copper exposure with Cl- absorption being the most sensitive parameter. Evidence for increased Na+ and fluid absorption when the fish exhibited elevated plasma osmolality indicates that the intestine may also exhibit a compensatory response to impairment of branchial transport processes, suggesting at least two target organs (gill and intestine) for copper toxicity in marine fish. Plasma Mg2+ was elevated from approximately 1.5 mM to as much as 4.0 mM, likely as a result of increased branchial permeability. While plasma [ammonia] clearly responded to copper exposure, plasma [urea] exhibited a much more sensitive and pronounced response to both acute and prolonged copper exposure, resulting in as much as a three-fold increase in circulating urea levels. This response is most likely the result of the unique ability of this teleost to convert ammonia to urea.

Animals↗
PubMedDate not supplied

[Specific organic compounds in the human waste products].

It is for the first time that chromato-mass-spectrometry has been used to examine human wastes. The data on the excretion rate of specific organic compounds can be employed to predict the content of toxic metabolites in the enclosed environment, to give their biomedical characterization, and to diagnose unfavorable changes in the body.

Feces↗
PubMed2003

Utilization of industrial waste products as adsorbents for the removal of dyes.

A number of low cost adsorbents from steel and fertilizer industries wastes have been prepared and investigated for the removal of anionic dyes such as ethyl orange, metanil yellow and acid blue 113 from aqueous solutions. The results indicate that inorganic wastes, i.e. blast furnace dust, sludge and slag from steel plants are not suitable for the removal of organic materials, whereas a carbonaceous adsorbent prepared from carbon slurry of fertilizer industry was found to adsorb 198, 211 and 219mg/g of ethyl orange, metanil yellow and acid blue 113, respectively. The adsorption of dyes on this adsorbent was studied as a function of contact time, concentration, particle size and temperature by batch method. The adsorption isotherm conformed to Langmuir model and the adsorption was found to be exothermic and physical in nature. Kinetic data conforms to Lagergren's equation with good correlation coefficients varying from 0.9998 to 0.9999 indicating that the adsorption is a first-order process. The adsorption data on carbonaceous adsorbent was compared to a standard activated charcoal sample and it was found that the prepared adsorbent is about 80% as efficient as standard activated charcoal and therefore, can be used as low cost alternative ( approximately 100 US dollars per ton) for colour removal from effluents.

Adsorption↗
PubMedDate not supplied

Toxicological investigations in the semiconductor industry: I. Studies on the acute oral toxicity of a complex mixture of waste products from the aluminium plasma etching process.

In dry etching processes--one of the sources of potential exposure to toxic wastes in the semiconductor industry--complex mixtures of inorganic and organic compounds arise from reactions between feed stock gases (BCl3/Cl2), top layers (aluminium photoresist), and the carrier gas (N2). Two different fractions of the complex mixture--one an ethanolic solution (ES) and the other an insoluble liquid residue (LR)--were examined for acute oral toxicity in rats. Analytical data showed that the ethanol soluble fraction contained mainly inorganic compounds, whereas the residue contained various halogenated hydrocarbons. Neither death nor behavioral changes occurred after oral administration and observation up to 23 days. ES caused a lower mean arterial blood pressure in both sexes, increased P-R-intervals in male rats, and caused some mild biochemical and hematological alterations and changes in relative organ weights compared to the control groups. Exposure to LR influenced food and water intake, and caused a significant decrease in body weights, signs of polyurie, as well as changes in various relative organ weights and biochemical and hematological parameters. The blood pressure of the male animals fell and the heart rates of both sexes decreased.

Aluminum↗