This paper determines the impact of the maturation process of composted sewage sludge on the quality of the final product and assesses the stabilization effect. The samples of composted sewage sludge were taken from a wastewater treatment plant located in Pomerania in northern Poland. The sewage sludge was composted in an open windrow composting plant with the addition of straw and wood chips in the turning windrow. The aeration of the sewage sludge mixture was conducted based on two methods. The first phase (intensive degradation phase of 6 to 8 weeks) was characterized by frequently turning; the second phase for maturation used aeration channels (2 to 3 months). In three sampling campaigns samples were taken from the same windrow after 2 (no. 1), 8 (no. 2), and 12 weeks (no. 3) of maturation. Fresh samples were used for analyzing the stabilization parameter as static respiration activity (AT₄). Furthermore, the values of pH, organic matter (OM), total organic carbon (TOC), elementary composition, nutrients, total content, and mobile forms of heavy metals were analyzed in the compost samples. A significant decrease was found in the stabilization parameter (AT₄) during the maturation of tested materials. In turn, no significant differences were found in the elementary composition. The concentration of most metals increased in the final product. The total content of heavy metals in the final product did not exceed the limit values for the agricultural use of sewage sludge, compost from municipal waste, and for organic fertilizers. There were no significant changes in the percentage of bioavailable and mobile forms of heavy metals during compost maturation. Zinc was characterized by the highest level of mobile and bioavailable forms, which may cause bioaccumulation after the fertilization of soil. The study has shown that the process of maturation of compost from sewage sludge not affects changes in the content of heavy metal forms. The scope of this study has been planned on a wider scale for different variants of sewage sludge composting, in order to evaluate the process.

This paper presents the results of the analysis of the chemical composition and content of heavy metal contamination in forest logging residues, in order to assess the possibility for their further utilisation. The samples were divided into 9 groups, which included coniferous tree cones, wood, and other multi-species logging residues. The elementary composition, ash content, and calorific value were determined as energy use indicators for the samples. Additionally, the content of heavy and alkali metals, which may affect combustion processes and pollutant emissions, was tested. The high content of heavy metals may also disqualify these residues for other uses. The research shows that the test residues are suitable for energy use due to their high calorific value and low content of heavy metals. However, an increased ash content in some samples and the presence of alkali metals, causing high-temperature corrosion of boilers, may disqualify them as a potential fuel in the combustion process. The forest residues may be used in other thermal processes such as pyrolysis or gasification. A low content of heavy metals and a high content of organic matter permit the use of these residues for the production of adsorbents or composite materials.

The aim of this study was to assess the degree of stabilization of composted sewage sludge (SSC) during maturation using tests in aerobic and anaerobic conditions, determining the potential for biogas formation and its composition, as well as changes of mobile and bioavailable forms of metals in SSC after treatment. The samples were taken in the second phase of composting, during the maturation process. The biological stability of SSC samples was determined by detecting an incubation test (GS21) and respiration index (AT4). The potential for biogas formation and composition changes of SSC during maturation were analyzed. It was found that the chemical composition of the tested samples depended on the degree of their maturity. It was found that the both tested methods (AT4, GS21) of assessing the stability of waste are sufficient. Treatment under anaerobic conditions did not significantly change the composition of the samples, with the exception of total organic carbon (TOC). A high percentage of methane in biogas for samples at the beginning of the maturation process indicates a high content of biodegradable organic matter in SSC. In addition, the decrease of mobile and bioavailable forms of heavy metals percentage, during the SSC maturation, was found. In order to confirm the results of current study, a long-term field studies should be carried out on the effects of SSCs tested on soils and plants.

Background: Lifetime (or long-term) exposure to air pollution has been linked to an increased risk of premature death. This association might persist even at low air pollutant concentrations level. The objective was to describe and compare lifetime exposures to PM₁₀, PM_2.5, NO₂, benzene, and benzo(a)pyrene in two differently polluted localities and quantify years of life lost due to all-cause mortality attributable to PM₁₀, PM_2.5, NO₂. Methods: The study population was selected from two differently polluted localities of the Czech Republic from the period 2000–2017. For determination of lifetime exposures specially developed methodology for historical air pollutants time series concentrations estimation was used. Estimated lifetime exposures, new WHO air quality guideline levels and relative risks were used to quantify years of life lost due to all-cause mortality attributable to air pollutants. Results: Significant differences in lifetime exposures of air pollutants between study areas were found. Average lifetime exposure to PM₁₀, PM_2.5, NO₂, benzene and B(a)P was 45.6 μg/m³, 34.9 μg/m³, 18.1 μg/m³, 2.1 μg/m³and 2.6 ng/m³, respectively, in high-polluted area, against 24.9 μg/m³, 19.4 μg/m³, 13.3 μg/m³, 0.8 μg/m³, 0.4 ng/m³ in low-polluted area. All-cause mortality and years of life lost due to all-cause mortality (non-external) were higher in high-polluted area. The highest contribution was found for PM_2.5, when the population attributable fraction was at the 23% level for the high polluted area and at the 14% level for the low polluted area. The highest losses of 35,776 years per 100,000 men or 131 days per 1 man were achieved in the high polluted area and in a case of PM_2.5 exposure, namely for men in the age category of 80–84 years. Additionally, the results were expressed per number of deaths. The average value for the number of deaths attributable to PM_2.5 exposure was 4.75 years per1 death man, or 3.51 years per 1 death woman in a high-polluted area. Conclusions: Expression of years of life lost due to all-cause mortality attributable to air pollution per number of deaths can be more appropriate for communication about health risks or in the field of public health protection.

The article assesses differences in lifetime losses caused by premature deaths from cardiopulmonary disease in populations living in areas with different environmental burdens. The results provide different perspectives on data on total years lost and lifetime losses attributable to air pollution. Such lifetime losses in the industrial area related to cardiovascular causes of death are 7.6 or 5.1 years per male or female deceased, representing an average lifetime loss of 0.01907 years (i.e. 7 days) per 1 male or 0.01273 years (i.e. 4.6 days) per 1 female in the entire population. Losses related to cerebrovascular or respiratory causes of death are about 5.4 or 5.9 years per 1 deceased male or 3.9 or 5 years per 1 deceased female, respectively, which represents a loss of 0.00481 (1.8 days), or 0.00148 years (0.5 days) per 1 male or 0.00466 (1.7 days), or 0.00058 years (0.2 days) per 1 female.

The health impacts of suspended particulate matter (SPM) are significantly associated with size—the smaller the aerosol particles, the stronger the biological effect. Quantitative evaluation of fine and ultrafine particles (FP and UFP) is, therefore, an integral part of ongoing epidemiological studies. The mass concentrations of SPM fractions (especially PM_2.5, PM_1.0, PM_0.25) were measured in an industrial area using cascade personal samplers and a gravimetric method, and their mass ratio was determined. The results of PM_2.5, PM_1.0 were also compared with the reference measurement at stationary stations. The mean ratios PM_2.5/SPM, PM_1.0/SPM, and PM_1.0/PM_2.5 were 0.76, 0.65, and 0.86, respectively. Surprisingly, a mass dominance of UFP with an aerodynamic diameter <0.25 μm (PM_0.25) was found with mean ratios of 0.43, 0.57, 0.67 in SPM, PM_2.5 and PM_1.0. The method used showed satisfactory agreement in comparison with reference measurements. The respirable fraction may consist predominantly of UFP. Despite the measures currently being taken to improve air quality, the most biologically efficient UFP can escape and remain in the air. UFP are currently determined primarily as particle number as opposed to the mass concentration used for conventional fractions. This complicates their mutual comparison and determination of individual fraction ratios.