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The spectrographic analysis of mineralized tobacco was carried out. A smoking simulator was constructed to generate smoke under standard conditions. The smoke of home-made cigarettes was absorbed in a previously tested absorbing system. The concentration of As, Cd, Co, Cr, Mn, Ni, Pb, Sb, and Se, was determined in a mineralized absorbent, and the content of the said elements in tobacco smoke inhaled by smokers, was defined.
The content of As, Cd, Co, Cr, Mn, Ni, Pb, Sb, and Se in the exhausted smoke from various sorts of home-made cigarettes, was determined. Basing on the results of metals content determinations in the inhaled smoke from these cigarettes, the retention of elements under test in a smoker's body was calculated, and their toxicity in terms of environmental exposure, was estimated.
Using AAS, the measurements of urine concentrations of lead, cadmium, and zinc, were carried out in workers of open-hearth steel and electrosteel plants. None of elements under investigation was an object of direct steelmaking process. Results of assays were compared with those obtained in subjects residing in the neighbourhood of steel works but being not at work in these plants. Average urine concentration of lead in open-hearth steel plant workers was 59.57 µg/dm3, and that determined in electrosteel plant workers was 56.87 µg/dm3. Both values were essentially greater than those determined in subjects residing in the neighbourhood of steel works (38.55 µg/dm3). Average urine concentration of cadmium in open-hearth steel plant workers, electrosteel plant workers, and subjects being not at work in steelmaking plants, was found to amount to 4.73 µg/dm3, 2.91 µg/dm3, and 1.48 µg/dm3, respectively. Average urine concentration of zinc in both groups of professionally exposed workers, was essentially lower than that determined in subjects being not at work (subjects exposed to environmental hazard).
The effect of methylene chloride, chloroform, and carbon tertrachloride on the following aquatic organisms: Pseudomonas fluorescens, Scenedesmus quadricauda, Lemna minor, Daphnia magna, and Lebistes reticulatus, was investigated. Pseudomonas fluorescens bacteria were found to be most sensitive test organisms, and a toxic effect towards them was observed just at the concentration of 100 µg/l of each agent. Studies on degradation in distilled water, river-water, and aqueous ecosystem revealed moderate stability in aqueous medium of compounds under investigation. Chloroform and carbon tetrachloride were detecable in river-water still after 40 days in concentrations toxic to aqueous ecosystem. More rapid degradation of methane halogen derivatives in river-water than in distilled water indicated the presence of microorganisms living in water from natural source, and being accessory to the decomposition of these agents. Degradation in the presence of adapted microflora took, as a general rule, a slower cource. Decrease of temperature to 6°C inhibited considerably the degradation rate of the investigated contaminants. The reduction of methane halogen derivatives content during 21-day exposure in aqueous ecosystem came up to 73%. Moreover, these compounds were found not to have biocumulative properties, and not to be toxic - in concentrations up to 300 µg/l - to aqueous biocenosis homing the experimental ecosystem.
Measurements of lead and cadmium content by AAS, and fluorine content by spectrophotometry based on complexing with alizarin, were carried out in vegetables and fruits harvested in 1989 in Inowrocław region. The highest lead concentration (on an average from 0.553 to 1.003 mg/kg of fresh product) was noted in overground of vegetables. Lead concentration in subterranean shoots did not exceed the tolerance limit of 0.3 mg/kg of fresh product, recommended by the Polish Standard. Maximum contamination with cadmium (on an average 0.052 mg/kg fresh product) was found in vegetables harvested in city gardens (the control area) whereas that in allotments varied from 0.023 to 0.052 mg/kg. Plants contamination with fluorine was not large and concerned only overground parts of marjoran, parsley leaves, onion leaves, and celery.
Using AAS, Pb, Cd, Zn, and Cu concentrations were measured in the brain, cerebrospinal fluid, liver, bile, and blood in 10 weeks old calves, 10 month old young beef cattle, and 10-12 years old cows. The lowest concentration of Cd was observed in claves' brain, the higher - in the cerebrospinal fluid, blood and bile, and the highest - in the liver. Cadmium content in tissues and body fluids of cows and young beef cattle, was found to be several times higher when compared with that determined in calves. Contrary to Pb and Cd, the highest concentrations of Cu were noted in the cerebrospinal fluid, liver and bile of calves when compared with those determined in young beef cattle and cows. Similarly, the highest levels of Zn were found in the liver, brain, bile and cerebrospinal fluid of calves in comparison with those determined in young beef cattle and cows.
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