The use of sludge in agriculture within the European Union (EU) is currently regulated only by the limits of heavy metals (Cd, Cu, Hg, Ni, Pb and Zn) listed in Council Directive 86/278/EEC. This document is now more than 30 years old. Several European countries have introduced more stringent requirements in comparison with the directive, and have adopted limits for concentrations of other heavy metals, synthetic organic compounds and microbial contamination. The paper provides an overview of the current limits of these substances in sewage sludge and concentration limits of heavy metals in soil intended for sludge application, together with applicable laws and regulations in European Union countries. There is a need to update these regulations taking into account the current risks associated with the application of sludge to agricultural land, with the possibility of using ecotoxicological tests to assess the risks. A wide range of technologies for sewage sludge processing is used in EU countries. The predominant choice is a direct application in agriculture followed by composting. The use of sewage sludge in agriculture in 2014 and 2015 in 13 EU countries that provided data amounted to 22.6% (2014) and 22.1% (2015) of produced sludge and 23.3% (2014) and 23.1% (2015) of sludge disposed. It is also highly variable within EU countries ranging between zero (Malta, Slovenia, Slovakia) and 80% (Ireland). Over 50% of sewage sludge is used in agriculture in Bulgaria according to 2015 data.

ABSTRACT:Peat is an easily available natural material and a source of biologically active substances widely used, not only in agriculture but in human and animal medicine as well. In recent years, interest in the use of peat as a feed supplement has increased, particularly due to its capability to prevent enteric diseases and to stimulate growth in piglets and pigs. The purpose of this review was to compare the advantages and risks associated with the use of peat for animal nutrition based on the literature available. Beneficial effects of various peat preparations on digestion, growth and the immune systems of animals as well as the absorbent and detoxifying capabilities are associated with the high content of favourable humic substances. One disadvantage of using peat preparations is the considerable diversity of the various types of peat caused by different biological, chemical and geological conditions during formation. Biological activity of various peat preparations is associated not only with fluctuations in the chemical compositions, but also with different application techniques. Based on the existing studies, it is unclear which application technique is most effective for respective animal species. Further studies should be conducted to elucidate the problem, with the inclusion of farm animals. One potential risk of peat feeding is the possibility of primary or secondary mycobacterial contamination. As long as feed rations are supplemented with peat preparations, it is essential to minimise the potential contamination risk during mining, processing and storage.

In this study, carried out within the Joint Danube Survey 4, a comprehensive microplastic screening in the water column within a large European river basin from its source to estuary, including major tributaries, was realized. The objective was to develop principles of a systematic and practicable microplastic monitoring strategy using sedimentation boxes for collection of suspended particulate matter followed by its subsequent analysis using thermal extraction desorption-gas chromatography/mass spectrometry. In total, 18 sampling sites in the Danube River Basin were investigated. The obtained suspended particulate matter samples were subdivided into the fractions of >100 μm and <100 μm and subsequently analyzed for microplastic mass contents. The results showed that microplastics were detected in all samples, with polyethylene being the predominant polymer with maximum contents of 22.24 μg/mg, 3.23 μg/mg for polystyrene, 1.03 μg/mg for styrene-butadiene-rubber, and 0.45 μg/mg for polypropylene. Further, polymers such as different sorts of polyester, polyacrylates, polylactide, and natural rubber were not detected or below the detection limit. Additional investigations on possible interference of polyethylene signals by algae-derived fatty acids were assessed. In the context of targeted monitoring, repeated measurements provide more certainty in the interpretation of the results for the individual sites. Nevertheless, it can be stated that the chosen approach using an integrative sampling and determination of total plastic content proved to be successful.

The aim of the study was to verify the effect of three diets containing 10% amaranth fed to pigs, on selected parameters of metabolism and health and on the growth efficiency in comparison with the control diet containing animal protein. The animals of each group were given the same diet during the entire period of fattening. Experimental and control groups of pigs (n = 10 in each; 5 males + 5 females) with live weight of 18 kg were partially ad libitum fed diets containing dried surface amaranth biomass or amaranth grain either non-heat-treated or heat-treated by popping, or a diet containing meat-and-bone meal for 100 days. No significant differences in the live body weight gains were detected between experimental and control groups. The highest daily body weight gain was recorded in animals fed the mixture containing heat-treated amaranth (0.78 kg) and the best feed conversion was detected in the group fed non-heat-treated grain (2.45 kg). The values of selected biochemical parameters ranged within the physiological limits.

The aim of this study was to assess mercury (Hg), cadmium (Cd) and lead (Pb) contamination in muscle tissue of fishes over the longitudinal profile of the River Morava (Czech Republic, Danube basin) and to detect any temporal trends over the past 18 years. Fish samples were collected in 1992, 1998, 2000, 2003 and 2009 at 6 study sites situated just downstream of important pollution sources. Chub (Leuciscus cephalus L.) were selected as indicator species at 5 sites, and brown trout (Salmo trutta m. fario L.) at the uppermost site where chub do not occur. In total, muscle tissue of 175 specimens of chub and 19 specimens of brown trout were analysed. Concentrations of heavy metals ranged as follows: mercury 0.015-0.369 mg/kg; cadmium 0.001-0.254 mg/kg and lead 0.006-1.505 mg/kg. Mercury levels did not exceed the maximum allowed concentration in the Czech Republic (0.5 mg/kg). Content of cadmium and lead in fish muscle exceeded the maximum allowed levels (0.05 and 0.3 mg/kg respectively) in 11 and 4 samples, respectively. On average, the order of metal concentration in fish muscle was: Hg>Pb>Cd. No significant differences were found between sites along the longitudinal profile of the river. Significant differences were found, however, for the interannual comparison of cadmium and lead (but not mercury) at different sites (P < 0.05). A catastrophic flood in 1997 resulted in an increase in metal concentrations, especially cadmium and lead, in the following 1998 season. Our results indicate that the Morava river basin does not represent a threatening source of mercury, cadmium or lead for the River Danube downstream.