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Little is known about thallium behavior in the environment, especially its interactions with microorganisms such as fungi. This article evaluates basic interactions (bioaccumulation, biosorption and growth inhibition) between thallium and the common heat-resistant fungal species Neosartorya fischeri. The results suggest that the N. fischeri strain is relatively resistant to elevated concentrations of thallium in cultivation media up to 1 mg・l⁻¹. However, the toxic effect of thallium on fungal growth depends on the time of cultivation, and after 30-day cultivation growth inhibition was reduced. The bioaccumulation of thallium after 30-day cultivation by fungal strain was 35.74 mg・kg⁻¹ and 432.91 mg・kg⁻¹ for initial concentration 1.012 and 4.861 mg・l⁻¹ of Tl(I) in medium, respectively. The biosorption capacity was calculated to be 11.77 mg・kg and 62.01 mg・kg⁻¹ for initial concentration 1.012, and 4.861 mg・l⁻¹ of Tl(I) in medium, respectively.
Thallium is a highly toxic element and very rarely studied in the context of environmental hazards connected with zinc and non-ferrous metal industry. Microorganisms naturally existing in post-flotation and smelt wastes can participate in thallium release from waste deposits and can contribute to its dispersion in the environment. Twenty-one isolates were obtained from wastes of a non-ferrous smelter in Southern Poland characterised by high heavy metal contamination. Ten isolates showed high activity in thallium leaching from wastes (post-flotation and smelt wastes) as well as from pure thallous sulphide. Additionally, cadmium and lead were bioleached from wastes. The isolated bacteria indicated thallium resistance at a concentration up to 100 mg/l and some of them were able to survive in good condition at a concentration of up to 4 g/l. The same bacteria were isolated from rivers and wastewater in this region. A preliminary characterisation of isolates was performed. It was shown that some petroleum products i.e. asphalt-base crude occasionally used for waste immobilisation at the edge of pond or flotation surfactants partially stopped the activity of sulphide oxidising bacteria.
Thallium is a metal with a high rate of accumulation in the environment and at the same time there is a very large dispersion of it. Heavy metal studies and its bioaccumulation and concentration in organisms and health implications are still not well known. The aim of this study was to demonstrate the importance of this element as an intoxicant of living organisms, especially on laying hens. Four groups of ISA Brown hens were used in this study. Experimental groups received feed containing thallium as thallium sulfate (Tl₂SO₄). Concentrations and metal accumulation in the animals were determined periodically, analyzing the eggs and animal blood. After the experiment, concentrations of thallium in the tissues was determined post-mortem. The studies showed a proportional accumulation of thallium in the body of the animals in relation to exposure time, and doses with the highest concentrations in the bones, kidneys, muscles, liver, and blood.
High thallium concentrations were found in plants and fungi growing 0.5-2 km from the flotation waste reservoir serving the Bolesław Mining and Metallurgical Works in Bukowno. Rinsed pine needles contained 2.20 ± 0.72 mg/kg d.w. thallium, moss Pleurozium schreberi 4.89 ± 2.00, moss Catharinea sp. 12.65, lichen Cladonia sp. 2.80 ± 1.01 and edible mushrooms 3.48-4.76. Vegetables from a village (Starczynów) closest to the reservoir contained 1.28-3.70 mg/kg d.w. thallium. The inhabitants are threatened by thallium pollution. In natural conditions the element concentrations in biological samples usually do not exceed 0.0X-0.X mg/kg d.w. Only fruit samples from the studied area and all the control samples were devoid of thallium.
The purpose of this investigation was to study the effects of aluminosilicates (vermiculite and bentonite), added to feed on thallium bioaccumulation in laying hens. The experiment was conducted on 48 layers kept in cages under vivarium conditions. The hens were divided into 4 groups: Group 1- control, Group 2 – thallium-intoxicated, Group 3 – thallium-intoxicated fed on feed containing vermiculite and Group 4 – thallium-intoxicated fed on feed containing bentonite. Thallium was added in the form of sulphate (Tl₂SO₄) at a daily dose of 0.74 mg/kg body weight. Thallium content was determined in blood and eggs on days 1, 14, 28, 42, 56 of the experiment and also in thigh and breast muscles, kidney, liver and thigh bone after the experiment was accomplished. Thallium content of the tissues and organs was determined using plasma spectrometry ICP-MS. The highest thallium concentration was found in bones 8.849 mg/kg, next in kidneys 7.596 mg/kg. Lower thallium content was found in muscles, liver and blood. The addition of bentonite reduce thallium accumulation most effective in muscles by 34.75-36.94% and blood 39.07%. The addition of vermiculite to the feed had reducing impact on thallium accumulation in the all tested tissues and organs of birds chronically intoxicated with this element (by 18.2% in kidneys – 55.71% in breast muscles).
Blood thallium level in 148 subjects employed in Zinc and Lead Works, Miasteczko Śląskie, and permanently exposed to secondary dusting, was investigated. Blood thallium concentration was found to range from 0.127 to 4.942 µG/cm3 and to be relative to the period of occupation, age of subjects, and their addiction to smoking.
Badano występowanie talu w pyle zawieszonym i w pyle zdeponowanym na liściach. Największe ilości tego pierwiastka stwierdzono w odległości 500 do 1000m od huty. Stwierdzono współzależność występowania talu z masą pyłu zawieszonego do odległości 2500m we wszystkich zasadniczych kierunkach geograficznych.
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