Long-Term Polyethylene (Bio)Degradation in Landfill: Environmental and Human Health Implications from Comprehensive Analysis.

This study investigates the process of long-term (bio)degradation of polyethylene (PE) in an old municipal waste landfill (MWL) and its implications for environmental and human health. Advanced techniques, such as ICP-ES/MS and IC-LC, were used to analyze heavy metals and anions/cations, demonstrating significant concentration deviations from control samples. The soil's chemical composition revealed numerous hazardous organic compounds, further indicating the migration of additives from PE to the soil. Toxicological assessments, including Phytotoxkit FTM, Microtox® bioassay, and Ostracodtoxkit®, demonstrated phytotoxicity, acute toxicity, and high mortality in living organisms (over 85% for Heterocypris Incongruens). An unusual concentration of contaminants in the MWL's middle layers, linked to Poland's economic changes during the 1980s and 1990s, suggests increased risks of pollutant migration, posing additional environmental and health threats. Moreover, the infiltration capability of microorganisms, including pathogens, into PE structures raises concerns about potential groundwater contamination through the landfill bottom. This research underscores the need for vigilant management and updated strategies to protect the environment and public health, particularly in older landfill sites.

Micropollutants in treated wastewater.

Compounds such as pharmaceuticals, or personal care products are only partially removed in wastewater treatment processes. Large number of these compounds and their degradation products is out of any control. A small number of compounds are covered by legal regulations. Among the compounds non-regulated by law, the target compounds, as well as non-target compounds can be distinguished. In the scientific literature, number of reports on various target compounds' determination is increasingly growing. This paper provides an up-to-date review on micropollutants present in treated wastewater and their concentrations found in literature in the years 2015-2019. Because the obtained results of chemical analyses do not adequately reflect the risks to ecosystems and consequently humans, the results of chemical analyses have been supplemented by a review of ecotoxicological studies. In addition, legal issues linked to contamination of treated wastewater and research related to identification of non-target compounds in treated effluents have been discussed.

Amino acid profile after oral nutritional supplementation in hemodialysis patients with protein-energy wasting.

OBJECTIVES: Protein-energy wasting (PEW) is highly prevalent in patients on hemodialysis (HD). Oral nutritional supplementation (ONS) is recommended for malnourished patients on HD. The aim of this study was to evaluate ONS on plasma amino acid in HD patients with PEW. METHODS: Thirty-two HD patients with a mean age 59.1 ± 9.5 y with PEW were enrolled into the study. Patients were prescribed ONS (125 mL twice a day for 3 mo) together with dietary advice. The nutritional status was evaluated by means of body mass index, Subjective Global Assessment, and serum albumin and prealbumin levels. The percentages of body fat and lean body mass were measured by means of the near-infrared method. The lean body mass-to-body weight ratios were calculated. Tumor necrosis factor, interleukin-6 and high-sensitivity C-reactive protein, were measured by the enzyme-linked immunosorbent assay method. Serum concentrations of amino acids were measured by the high-performance liquid chromatography method. RESULTS: After 3 mo of ONS, a significant increase of both serum prealbumin and albumin was observed. The concentration of most of the amino acids increased independently on inflammation. CONCLUSIONS: Dietary advice, combined with ONS, is effective in HD patients with PEW. Both dietary advice and ONS are needed to be sure that patients consume an adequate daily amount of calories and protein.

Elemental sulfur in sediments: analytical problems.

In the paper, a modified method for elemental sulfur (S8) determining using gas chromatography coupled with mass spectrometry (GC-MS) is proposed with estimation of selected validation parameters. The aim of this work was a review of problems associated with the determination of S8 and selection of the most optimal conditions for S8 analysis with GC-MS. The presented studies have shown that the temperature of the injector and the chromatographic column during S8 determination should not exceed 180 °C. At temperatures over 180 °C, the sulfur S8 is decomposed to the other sulfur species such as S2, S3, S4, S5, and S6. During decreasing injector and column temperature below 180 °C the chromatographic peak eluted as S8 is badly extended and asymmetric. To minimize the problems of S8 decomposition to other sulfur species during chromatographic process also other parameters of the GC-MS have been selected. In order to apply the proposed method for real sediments samples, determination of sulfur S8 in bottom sediments, collected in the Gulf of Gdansk (southern Baltic Sea), has been performed. The concentration of S8 fell in the range from below the limit of detection to 0.1432 ± 0.0095 mg/g d.w. The research has also shown that addition of approx. 200 mg of activated copper is effective for removing sulfur from bottom sediment extracts.