Volume 42 (2011): Issue 1 (January 2011)

This article presents the concept of geochemical background from an environmental perspective. The idea of establishing the typical concentrations of elements in various environmental compartments, proposed by exploratory geochemists almost 50 years ago was important for the detection of anomalous element concentrations, thus providing a basic tool in the search for new mineral deposits. At present, the knowledge of the geochemical background of hazardous elements is essential for: defining pollution, identifying the source of contamination, and for establishing reliable environmental quality criteria for soils, sediments and surface waters. The article presents geochemical methods of evaluation of anthropogenic influence on the environment and discusses the problem of defining and understanding the term "geochemical background" and related terms in environmental sciences. It also briefly presents methods of geochemical background evaluation based on the results of environmental sample analyses. It stresses the role of geochemical background in our understanding of environmental pollution and pollution prevention.

In sludge samples collected in the "Centrum" wastewater treatment plant in Siemianowice Śląskie, Poland, the composition of aliphatic- and aromatic hydrocarbons and polar compound fractions were investigated by gas chromatography-mass spectrometry (GC-MS). Samples collected in accordance with Polish standards were extracted, the extracts were separated into fractions with preparative thin layer chromatography (TLC), which next were investigated by GC-MS. The following compound groups of the geochemical origin were identified: n-alkanes in the range of n-C₁₄ to n-C.₃₉, acyclic isoprenoids (mainly pristane and phytane), steranes, tri- and pentacyclic triterpanes. Based on the distribution of biomarkers and their parameters, it was established that the dominant component of extractable organic matter in sluge is petroleum material of an unspecified origin. Its geochemical features indicate that its most likely source was crude oil (or its products) of a relatively high degree of thermal maturity (catagenic stage of thermal evolution corresponding to vitrinite reflectance 0.7-0.8%). Aromatic hydrocarbons probably originated from petroleum also, though some of them can be attributed to the products of combustion or to sources such as bituminous coals, the ash from coal/biofuel combustion or coal wastes stored nearby.

δ³⁴S and δ¹³C analyses were used to determine the origin of trout specimens. The isotope record of their scales and muscles are compared with a database previously obtained from wild- and reared fish coming from Polish rivers and pond farms. The comparison made it possible to find out whether the trout were wild or reared.

Bituminous to anthracite coals from three small Stephanian intramontane coal-bearing basins (La Magdalena, Cinera-Matallana and Sabero) located along the Sabero-Gordón fault line strike-slip systems of the Southern Cantabrian Zone (SCZ) were examined. Coal rank expressed as mean vitrinite reflectance values of these Stephanian coals is in the range 0.72-3.96%. The vitrinite maceral group exceeds 72 vol. % in all of the coals. The coals are characterized by relatively variable contents of mineral matter and coal-ash. The mineral matter comprises, in the main, clay minerals, carbonates, sulphides and quartz. The coals exhibit medium-high concentrations (see for comparison Ronov et al. 1990; Kabata-Pendias, Pendias 1999; Ketris, Yudovich 2009) of the following elements (in ppm): ΣREE (53-205), Ba (300-900), As (11-57), Zn (<50-150), Cr (10-160), Rb (50-145), Co (5-26), Sc (2-24.6), Ce (17-99), Yb (1.3-4.5), Th (2.4-11.9) and U (1.1-8.1), Br (<1-14), Cs (<2-9), Eu (<0,3-1.5), Lu (0.11-0.85) and Sb (0.8-4.8), and relatively low concentrations of Sm (0.6-6.6) and Ta (<1-2). They are also characterised by relatively high Th/U values (1.31-2.29). LREE/HREE values fall in the range 24-44 (average - 30). In contrast, concentrations of Au, Ag, Hg, Ir, Ni, Se, Sn, Sr, and W are below detection limits for the applied INAA method. As the concentrations of elements are significantly higher in coal-ash, most are likely related to mineral matter in the coals.

We report the results of high-precision (±0.05‰) oxygen isotope analysis of phosphates in 6 teeth of fossil sharks from the Mangyshlak peninsula. This precision was achieved by the offline preparation of CO₂ which was then analyzed on a dual-inlet and triple-collector IRMS. The teeth samples were separated from Middle- and Late Bartonian sediments cropping out in two locations, Usak and Kuilus. Seawater temperatures calculated from the δ¹⁸O data vary from 23-41°C. However, these temperatures are probably overestimated due to freshwater inflow. The data point at higher temperature in the Late Bartonian than in the Middle Bartonian and suggest differences in the depth habitats of the shark species studied.

The aim of this work was to assess the contamination of the landslide lakes located within Babiogórski National Park. For this purpose, samples of water and bottom sediment from 12 lakes were collected. Chemical analyses of the waters (including main cation and anion concentrations, trace-metal levels and selected physicochemical parameters) and of the sediments (including heavy metals) were performed. The waters are acidic to neutral and are characterized by low mineralization. Concentrations of trace elements are commonly low. Elevated levels of Fe, Mn and Al are probably related to natural geochemical processes. The sediments are strongly contaminated by Cd, whereas other trace metals levels are at their hydrogeochemical background. The high level of Cd contamination is most probably related to long-range industrial emissions.