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R Umińska

Publications and source records attributed to R Umińska.

5 recordsLinked to original sources
PubMed1990

[Selenium in human environment].

Selenium belongs to the group of elements which may be regarded as useful only in a very narrow range, while in excess doses they exert a harmful action. The content of the element in soil is usually from 0.1 to 2 mg/kg, with the Scandinavian soils have a low level of selenium, not exceeding 0.3 mg/kg. The highest level, exceeding 3000 mg/kg was noted in Northern Ireland. Selenium content in soil over 500 mg/kg produces chronic selenium intoxication in domestic animals. Selenium accumulation by plants is a selective process and depends on the chemical state of the element in soil and pH of soil. It is considered that the daily requirement for selenium is 50-300 mcg for adults, while the toxic dose is regarded as 5 mg daily. The toxic effects of selenium in the environment include inflammatory processes of the extremities in herbivorous animals (the so called Degnal disease in India and the Alkali disease in Great Britain). Selenium deficiency in the environment leads to the so called white muscle disease in these animals in Great Britain. Selenium is considered also to protect the organism in case of poisoning with lead, mercury or cadmium.

Dose-Response Relationship, Drug↗
PubMed1990

[Content of metals in vegetables from various regions of Poland in the years 1986-1988. I. Content of lead, cadmium and mercury].

The content of lead, cadmium and mercury was determined in various sorts of Polish vegetables grown on soil or in hothouses in the years 1986-1988 using for the determination of Pb and Cd the extraction flame ASA method after dry mineralization at about 400 degrees C and for Hg the flameless ASA method after wet mineralization. In 1988 soil investigations were conducted parallelly in the areas where these vegetables had been grown. Vegetable samples were taken directly from the producers in 18 provinces, from areas not contaminated with these metals by industrial plants and traffic. About 2.5 thousand vegetable samples and about 650 soil samples were investigated. A considerable part of the vegetables, especially those whose roots are consumed, contained excessive amounts of lead--over 0.3 mg/kg (e.g. over 20% of samples of parsley leaves) and cadmium--over 0.3 mg/kg (nearly 40% of carrots samples, and about 30% of beets, lettuce grown on soil or in hothouses, and parsley roots, about 20% of samples of parsley leaves grown on soil). The levels of mercury were usually of the order of thousandths mg/kg. The mean values of these metals in soil were frequently much higher than the values regarded as most frequent in the soils of not contaminated regions of Poland.

Cadmium↗
PubMed1990

[Content of metals in vegetables from various regions of poland in the years 1986-1988. II. Content of zinc and copper].

The content of zinc and copper was determined in various sorts of vegetables grown in hothouses or on soil. This content was determined also in the soil where these vegetables were grown. The samples of these vegetables were taken directly from the producers in 18 provinces of Poland from the areas not contaminated by industrial plants and traffic. The content of Cu and Zn was determined after dry mineralization of samples at 400 degrees C by ASA method in adequately diluted aqueous solutions of the mineralized substances. In all 2522 samples of vegetables grown in hothouses or on soil and 635 samples of soil were studied. The zinc level in most samples was lower than the permissible level 10 mg/kg. The highest amounts of zinc were found in red beets, and in the leaves of parsley grown in hothouses and on soil. The copper content in these samples was much below the permissible level of 4 mg/kg. The mean values of copper and zinc in soil samples were higher than the values accepted as present most frequently in soil in non-contaminated regions of Poland, that is 15 and 90 mg/kg respectively.

Copper↗
PubMed1987

Evaluation of mercury level in waters, bottom sediments and soils in selected rural areas.

The studies carried out aimed at evaluation of the mercury level in waters, bottom sediments and soils in selected rural areas, during the season of mercury biocides application and after their withdrawal from agricultural use. Generally, in the period between 1976-1980 the mercury level in 1268 environmental samples has been examined. Shallow dug wells of bad technical state and wrong location particularly exposed to contamination, have been selected for the studies. Mercury level has been determined after mineralization with concentrated acids by means of flameless method of atomic absorption spectrophotometry. The results have been compared with standards for mercury level in drinking waters (1 microgram/l) and in surface waters (5 micrograms/l), with the Warren-Devault criterion for soils (0.25 mg/kg) and with the value 1 mg/kg adopted as maximum natural mercury level in bottom sediments. The results have also been the subject to statistical analysis by means of the Tsao-Fei method and t-test. Mercury level in well waters, surface waters, bottom sediments and soils varied according to the region and the year of study and were respectively: 0.08-26.00 micrograms/l; 0.00-25.20 micrograms/l; 0.02-91.91 mg/kg; 0.01-24.94 mg/kg. Mercury levels of several dozen micrograms/l (waters) and several dozen mg/kg (bottom sediments and soils) have been recorded only in a few cases. A statistically significant decrease of mercury level in the environment of the regions investigated coincided with mercury biocides withdrawal from agricultural practice in our country.

Fresh Water↗