Quantification of soil plasticity is usually based on Atterberg limits or indices, which are then used for engineering and agricultural purposes on clay soils. Because these limits/indices are seldom ...analyzed during routine soil surveys, they are sometimes estimated from available soil properties using pedotransfer functions (PTFs). Main aim of this study was to test if two robust PTFs, previously created by other authors for other soils/areas, may be used for predicting plasticity of typical clay soils on fluvial deposits in Croatia. We analyzed mineralogy, plasticity, and related physicochemical properties of four representative soil profiles along Sava and Drava, two longest Croatian rivers. Particle size distribution patterns pointed to more uniform sedimentation along Sava, compared to Drava. Also, more clay was found within Sava profiles. Soil texture was finer farther away from the sources of both rivers. Soil cation exchange capacity (CEC) was almost fully positively correlated to clay content. On the other hand, C
org
content showed no correlation to CEC. This is attributed to the significant presence of smectite across all studied soils. Clay was recognized as the main factor influencing soil plasticity. When compared to the measured values, the predicted values of plasticity index and liquid limit were heavily underestimated. Hence, region-specific PTFs should be developed for more accurate prediction of plasticity in these soils. According to the WRB-2015, the soils were classified as Eutric Reductigleyic Stagnic Gleysols (Clayic, Humic, Protovertic). Because soils were not dry during field description, shrink-swell cracks were not prominent, and therefore soils were not classified as Vertisols. We suggest that field criteria for classification of Vertisols should not depend on actual soil moisture. Instead, plastic limits/indices could be used.
•24 elements in 7 different honeys collected in southern Croatia were analysed.•Significant differences in element concentrations were found among the honeys.•Honeydew honey had the high ...concentrations of almost all the elements determined.•Mandarin orange-blossom honey had the lowest concentration of elements determined.•Obtained results support the role of botanical origin on the honeys element composition.
The concentrations of 24 elements in seven honey types (multifloral, heather, common heather, bearberry, sage, mandarin orange-blossom and honeydew) collected in southern Mediterranean regions of Croatia were determined using ICP-MS. Significant differences were found in the concentrations of Ag, As, Ba, Cu, Co, Fe, K, Mg, Mn, Mo, Na, Ni, Se, Sb, U and Th (p<0.05, all) among honeys. The highest element concentrations were determined in honeydew honeys, with the exception of multifloral (Ca, Cr, Mo, Se), common heather (Mg, Na), bearberry (Ba, Fe, Pb) and sage (Ag) honeys. Among the floral honeys, the highest concentrations were found in multifloral honey (Al, As, Be, Ca, Cr, Mn, Mo, Ni, Se, Th and U), common heather (Co, K, Mg, Na, V), sage (Ag, Cd, Cu), and bearberry (Ba, Fe, Pb, Sb, Zn). The results contribute to the evidence supporting the role of botanical origin on the elemental composition of honey.
The review describes the results of clinical-epidemiological studies of 58 patients with the upper urinary tract urothelioma (UUTU) and of 261 patients with the renal cell carcinoma (RCC) performed ...over a period of 11 and 12 years, respectively. The subjects were domiciled in Croatia, Bosnia and Herzegovina, and the territory which now belongs to FR Yugoslavia. Some came from areas with endemic nephropathy. A comparison within groups clearly suggested a significantly marked epidemiological and clinical differences between the "endemic" and "nonendemic" UUTU and RCC patients. Different biological behaviour of the "endemic" UUTU, often accompanied by changes in renal parenchyma typical for endemic nephropathy, considerably changed the treatment results. An analysis of family and residential histories excluded the genetic basis and suggested environmental aetiology of the disease. There was a remarkable difference between the incidence of UUTU in patients from endemic areas, defined by living in affected households, and its incidence in patients living outside endemic areas. In some cases, the analysis of personal and family histories and of residence revealed the occurrence of a complex clinical picture of chronic tubulointerstitial nephritis and UUTU in some patients and members of their households. Chronic renal failure caused by the lesion of renal parenchyma typical for endemic nephropathy was the principal complication in the treatment of "endemic" RCC and a usual noncarcinomatous cause of early and late postoperative mortality of patients. An analysis of personal and residential histories excluded the genetic basis and suggested environmental aetiology of the disease. As in UUTU patients, the difference between the incidence of RCC in patients from endemic areas and patients living outside endemic areas was remarkable. An analysis of personal and family histories and of residence revealed the occurrence of a complex clinical picture of chronic tubulointerstitial nephritis and RCC in some patients and members of their households. The author traces the "endemic" UUTU and RCC to endemic nephropathy and merges them into one unique disease. The disease is considered as a single rural household environmental disease of the entire urinary tract due to shared dwelling and nourishment, without a precisely defined, but usually long latency. Clinical manifestations, including chronic renal failure due to the tubulointerstitial nephritis, renal cell carcinoma, and urotheliomas observed with a significantly higher incidence in the affected population, represent a complex and unique nosological entity.
This paper presents results of long-term investigations of radioactivity in general and occupational environments in the Republic of Croatia. Investigations of environmental radioactivity and ...occupational exposure monitoring in Croatia have been systematic since the early sixties. Investigations included radioactivity of the air, fallout, soil, river, sea and lake water, tap water, human foodstuffs, and animal feed. External dosimetry monitoring is carried out for workers occupationally exposed to ionising radiation in medicine, and industry. Radioactive contamination with fission radionuclides is associated with deposition of fallout originating from atmospheric explosions of nuclear weapons as well as from regular operation of nuclear facilities. Among hundreds of different radionuclides contained in various types of fallout only a few significantly contribute to the dose, particularly super(90)Sr and super(137)Cs. The maximum radioactive contamination with fission radionuclides was recorded in the early sixties, at the time of most intensive atmospheric nuclear tests. The fallout radioactivity has been exponentially decreasing ever since. The nuclear accident at Chornobyl temporarily raised super(137)Cs radioactivity levels in Croatia, whereas the increase in super(90)Sr radioactivity was not significant due to its low volatility. After a short-term increase, radioactivity dropped back to the pre-Chornobyl levels. Apart from radioactivity of fission products, investigations involved natural radioactivity and technologically enhanced natural radioactivity. Particular attention has been paid to radon as the most relevant source of natural radiation for humans. In 1998, the average absorbed dose in the air was 0.128 plus or minus 0.004 mu Gy/h. Consequently, an average Croat received the annual dose of 1.12 plus or minus 0.04 mSv through exposure to background radiation. However, as the overall collective dose includes the dose received by medical and civil use of radiation sources, significant effort has been put on the quality control of radiation sources (systematically implemented since 1985) as an important step for reducing the overall collective dose of Croatian population.
Persistent organic pollutants (POPs) are organic compounds resistant to photolytic, chemical and biological degradation. They are characterised by low water solubility and high fat solubility, which ...results in bioconcentration in fatty tissues of living organisms. In the environment, POPs are present at low levels and can travel long distances via water and air. This is why POPs can be found all over the world, including areas where they have never been used. Organochlorine pesticides (DDT, aldrin, dieldrin, hexachlorobenzene, and hexachlorocyclohexane) and polychlorinated biphenyls (PCB) are two groups of POPs intensively used worldwide. Unlike these compounds, polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) do not have practical application in industry. These four groups include over four hundred compounds; some of them are classified as carcinogens while others are considered potential carcinogens. Levels of organochlorine compounds in our population have been monitored since 1975. Initially, the investigation was limited to organochlorine pesticides, but later it expanded to all PCBs. Investigations included serum samples collected from general population and from exposed workers as well as human milk samples from general population of lactating women. Samples were collected in Zagreb, Osijek, Labin, Jastrebarsko, Karlovac, Sisak, and on the island of Krk. The main DDT metabolite p,p'-DDE and PCB were found in all analysed samples, serum and milk. Other pesticides or their metabolites ( alpha -, beta - and gamma -HCH, HCB, p,p'-DDT, p,p'-DDD) were not found in all samples. No marked differences were found between samples taken from individuals living in different geographic areas, but the levels indicated a downward trend. Since 1975 serum p,p'-DDE levels, which were then 31 mu g/L, have dropped about ten times. Human milk levels were 1,900 mu g/kg milk fat in 1981/82 and now are about six times lower. For the past twenty years PCB levels in serum and milk have also dropped about three times, yet they seem to have stabilised over the past five years. As lack of equipment bars dioxin analyses in Croatia, it was performed by qualified institutions in the USA, the Netherlands, and Sweden. Dioxin levels found in human milk samples collected in Zagreb, Krk, Jastrebarsko, Labin, and Osijek in 1981 - 1997 kept between 8.4-26.7 I-TEQ ng/kg milk fat (expressed as TCDD toxic equivalents according to international toxicity factors). A comparative study organised by the World Health Organization showed a 1.8% annual decrease from year 1992 to 1987 in samples collected in Zagreb and Krk. By contrast, other European countries and Canada showed a 7.2% decrease. However, one should take into account that levels in milk samples collected in Croatia are in the lower half of the concentration range determined in samples from other European countries, Canada, and Pakistan and it would not be reasonable to expect that the Croatian samples show a similar drop in dioxin levels. Samples collected from occupationally exposed workers who worked either with organochlorine pesticides or PCB showed slightly higher levels than samples from general population, but still kept below a threshold at which acute signs of exposure are expected. The daily intake of organochlorine compounds was evaluated for breast-fed infants from levels in human milk, and for adults from the analysis of foodstuffs. The intake by the adult population in our country was below the acceptable daily intake (ADI) values; nursing women showed higher levels than nonnursing women of the same age. This was not the case with breast-fed infants whose daily intake was higher than the ADI values in previous studies, but below ADI in recent studies. It may appear that the population of breast-fed infants is more exposed than adults, but one should keep in mind that the breast-feeding period is short in relation to the whole life, and that the benefites of breast-feeding prevail over the risk of intake of organochlorine compounds. To sum up, our investigations show that levels of organochlorine pesticides, polychlorinated biphenyls, and dioxins in Croatia keep within the lower half of the concentration range found in developed and industrialised countries.
Systematic collection of data on cancer incidence started in the US and Europe in 1930s. Today, cancer registries have an increasingly universal coverage. The application of a cancer registry may ...extend to include follow-ups, cancer etiology research, and cancer control programs. Of course, the applicability of a cancer registry depends on reliability and utility of the data. Cancer registries are best known for their potential to describe incidence, survival, and prevalence of cancer on a national and international level. Although poorer in quality, mortality data are frequently used in comparisons, as these are more readily available in many countries than the morbidity data. Studies of cancer incidence reveal etiology of cancers, through, for instance, observations of differences in incidence between areas, through migrant studies, or through studies of specific exposed groups (descriptive studies). A registry may serve as a referential point for a hypothesis on the roles of diet, environmental hazards, infections, and so on in the development of cancer. In epidemiological studies, the registry is used for correlational studies, case identification in case control studies, as well as to define cohorts, or the end-point of a cohort followup. Recently, the recording of data has extended not only to the anatomical site, but also to the morphology of a tumour, which serve more adequately to etiological studies. However, the assessment of a specific exposure is often poor, as the scarcity of cases often forces the researchers to group the data. Registries may also help to link data on an individual level, that is, in the area of genetic epidemiology. This study made use of the Croatian cancer registry founded in 1959 to investigate specific geographical distribution of cancer incidence by site - esophageal cancer, gastric cancer, colonic cancer, rectal cancer, biliary bladder cancer, lung cancer, cancer of the mammae, melanoma, cancer of the prostate, urinary bladder cancer, renal cancer, thyroid cancer, and myeloic leukemia. The objectives of the study were to see how causative agents differed in impact and to define the scope of investigations in cancer epidemiology. The investigation involved age-standardized average annual incidence rates in 17 geographical areas in Croatia for the period 1991-95. Nearly all geographical areas differed from one another in the incidence by cancer site. Interregional differences in cancer incidence in Croatia may reflect the action of multiple factors such as population characteristics, macroenvironment, and microenvironment. The results indicate a need for further studies and invite the use of epidemiological modelling, given the potentials of information technology.
Polycyclic aromatic hydrocarbons (PAHs) are a group of organic compounds with two or more benzene rings. They are a product of incomplete combustion of fossil fuels and other organic matter. PAHs are ...present in low concentrations in the air, especially in summer. However, the fact that many were found to have a mutagenic or carcinogenic effect drew more attention to them. Hundreds of PAHs have been identified in the air with BaP dominating in frequency and cancerogenic properties. The review describes an assessment of exposure to PAHs in 15 subjects through comparison between recorded PAH levels and time spent in various microenvironments and directly measured personal exposure. The average results did not significantly differ, but the BaP levels were close to or a little above guidelines for the limit value. This finding calls for immediate measures to reduce emissions of PAH.
Conodont ecology of the Early Triassic Smithian–Spathian transition is still poorly understood. Here we use oxygen isotope ratios of monogeneric conodonts from Omani samples to reveal the differences ...of oxygen isotopic composition between different taxa. Oxygen isotope analyses from Oman reveal that Neogondolella inhabited a deeper part of the water column relative to neospathodids and Icriospathodus. This indicates that species of Neogondolella lived in an environment ca. 1.7 °C cooler than where neospathodids lived. The investigation of conodonts from these Smithian and Spathian sections has also enabled the first recovery of some rarely reported species (e.g., Icriospathodus zaksi, Paullella omanensis sp. nov. Chen and Gladigondolella laii sp. nov. Chen) from Oman. Paullella omanensis sp. nov. was further recovered from Plavno, Croatia, indicating a large geographic distribution, and its value for biostratigraphic correlations. The discovery of these species in both Oman and Croatia expands their geographical distribution.
•Conodont ecology of the Early Triassic Smithian-Spathian transition is revealed via isotopic composition.•Neogondolella inhabited a deeper part of the water column relative to neospathodids and Icriospathodus.•Species of Neogondolella lived in ca. 1.7 °C cooler environment than where neospathodids lived.•The investigation has enabled the recovery of two new conodont species.
This paper analyzes vertical PGA strong-motion estimates for the city of Osijek. Osijek serves as a case-study area for low to medium seismicity regions with deep soil and deep geological sediments ...underneath the local soil. The new regional PGA attenuation equations for vertical ground motion are constructed for this purpose, as are the accompanying seismic micro-zoning maps. The vertical PGA values of different regional real strong motion are compared to the empirical PGA estimates. Finally, vertical to horizontal PGA estimation ratios are computed and examined. The results suggest that the vertical PGA design values for the examined area can be approximated as 0.61 of horizontal PGA values, which is a 37% higher ratio than the one given by Eurocode 8 for Type 2 spectra in 2004. When the recorded data from similar regions increases several-fold compared to what is now available, it will be possible to better calibrate the empirical scaling equations and to produce more credible vertical PGA estimates.
•Sites with deep soil atop geological sediments in low to medium seismicity regions.•New regional attenuation equations for PGA values in vertical direction.•Seismic hazard micro-zoning maps for the case-study area – the city of Osijek.•Average vertical to horizontal PGA ratio equal to 0.61 for all return periods.•Vertical to horizontal PGA ratio 37% larger than for Eurocode 8 Type 2 spectra.
PDF