Differential accumulation of low-chlorinated (Delor 103) and high-chlorinated (Delor 106) biphenyls in human placental tissue and opposite effects on conversion of DHEA to E2

OBJECTIVE: Polychlorinated biphenyls (PCBs) and related compounds elicit a diverse spectrum of toxic responses. Additionally, they are able to pass through the human placenta. The aim of the presented data was to compare the action of low-chlorinated (Delor 103) and (Delor 106) high-chlorinated biphenyls on placental steroidogenesis. METHODS: Explants of human placental tissue were used to test differences in PCBs accumulation and influence on placental steroidogenesis. Delor 103 or 106, were added daily for six days at a dose of 200 pg from day 0 to day 6 of culture. The media in the control and experimental groups were changed every day, and collected and frozen for steroid analysis by RIA. Determinations of PCBs of tissue and medium were analysed by GC/MS/MS. RESULTS: Delor 103 was found at a higher level in the tissue than Delor 106. The first day of exposure to Delor 103 had no effect on the conversion of dehydroepiandrosterone (DHEA) to estradiol (E2) while there was a 2-fold decrease in E2 secretion from days 3 to 6. Conversely, Delor 106 caused an immediate increase in E2 secretion, which was maintained at higher levels throughout the exposure period. CONCLUSION: Differences between the accumulation of lower chlorinated and higher chlorinated biphenyls in human placental tissue and in the properties of the congeners can have multiple effects that may intensify or counteract the effects on uterine contraction by PCBs.     

The earliest occurrence of the steppe pika (Ochotona pusilla) in Europe near the Pliocene/Pleistocene boundary

The steppe pika (Ochotona pusilla), a representative of the lagomorph family Ochotonidae, is restricted today to Kazakhstan and Russia. This subspecies-rich form belongs to a morphologically distinct, monospecific group of relatively small pikas, inhabiting steppe-like habitat. In the fossil record, it serves as a bioindicator of dry, grassland environment. The steppe pika was abundant and widespread in Europe during the Last Glaciation, and its unquestionable presence has been reported there since the middle Pleistocene. A new discovery of O. pusilla, from the Kielniki 3B locality (Poland), dated to the latest Pliocene, moves back the species appearance in Europe about one million years, almost coeval with its first record from the late Pliocene of Kazakhstan. Presence of such a typical steppe inhabitant as O. pusilla indicates significant climate change towards more arid, continental conditions, which started influencing Europe at 2.6 Ma. We present the first reliable record of the earliest O. pusilla entry deep into Europe in the latest Pliocene.     

Toxicity assessment of wood preservatives

The article describes the influence of wood preservatives on water bioceonosis. The “battery” of toxicology tests was used to cover luminescent bacteria test, algae growth inhibition test, crustacean and fish lethal tests. The test samples used were pure wood preservative and water after the wood preservative leaching from wood sample. It was observed that the wood preservative is leaching from the wood sample in 10% within 1 month of exposition. Achieved results indicate the necessity of toxic assessment of wood preservative after wood element protection.     

Dioxins and furans in biochars,hydrochars and torreficates produced by thermochemical conversion of biomass: a review

Converting raw biomass into valuable products protects the environment, improves economics, and helps tackle climate change by cutting resource demand and waste production. Thermochemical treatment is a common method for producing biochars, hydrochars and torreficates from biomass and organic wastes, which can also generate dioxins and furans and consequently limit the use of thermochemically converted chars. Here we review the presence of dioxins and furans in chars produced by hydrothermal carbonization, torrefaction, and pyrolysis processes under the influence of temperature, residence time, heating rate, pressure, and feedstock type. Dioxins and furans were mostly below 20 ng total toxic equivalence per kilogram (TEQ kg⁻¹), with the highest level of 113 ng TEQ kg⁻¹ found in over 100 samples of different char types. The most toxic products were hydrochars produced from sewage sludge. Processing temperature and feedstock type were key factors resulting in high dioxin levels in chars, and care should be taken when producing chars at temperatures up to 300 °C or using feedstocks previously contaminated with dioxins or preservatives.

     

Lead accumulation and elimination in tissues of Prussian carp, Carassius gibelio (Bloch, 1782), after long-term dietary exposure, and depuration periods

We studied the bioaccumulation of lead in selected tissues of Prussian carp Carassius gibelio (Bloch, 1782) during 12 and 24 months exposure to different doses of this metal in feed and the elimination of lead from tissues during the following 12-month depuration period. Lead concentration was determined using atomic absorption spectrometry method. The highest lead concentrations were observed at 2.0?±?0.54 to 7.4?±?1.1 mg?kg^?1 in the kidney, 3.0?±?0.13 to 5.2?±?0.17 mg?kg^?1 in the bone, and 4.5 (±0.4)?mg?kg^?1 in the hepatopancreas of fish from groups exposed to lead dietary concentration from 8 to 49 mg?kg^?1 for 24 months. The rate of accumulation were generally the highest at the beginning of exposure as evidenced by the highest monthly increments of bioaccumulation observed after 3 months of contamination for muscles, hepatopancreatic gland, intestine, and gills. Also analysis of the monthly increments of lead bioaccumulation in bone tissue and the highly significant coefficients of correlation indicate that the dynamics of accumulation are clearly dependent on dose of exposure. Depuration of accumulated lead from the organs depended mainly on tissue and duration of elimination period. Very rapid depuration was observed in soft tissues such as the intestine or muscles. Very low elimination was observed for scales and bones where until the end of the experiment highly significant lead concentration differences were observed in all groups in relation to the control group. Chronic dietary exposure in the range of 8–49 mg Pb?kg^?1 resulted in no significant effects on the growth and survival of Prussian carp females.     

Assessment of microbial contamination within working environments of different types of composting plants

The objective of the study was to determine the degree of microbiological contamination, type of microflora, bioaerosol particle size distribution, and concentration of endotoxins in dust in different types of composting plants. In addition, this study provides a list of indicator microorganisms that pose a biological threat in composting facilities, based on their prevalence within the workplace, source of isolation, and health hazards. We undertook microbiological analysis of the air, work surfaces, and compost, and assessed the particle size distribution of bioaerosols using a six-stage Andersen sampler. Endotoxins were determined using gas chromatography–mass spectrometry (GC-MS). Microbial identification was undertaken both microscopically and using biochemical tests. The predominant bacterial and fungal species were identified using 16S rRNA and ITS1/2 analysis, respectively.?The number of mesophilic microorganisms in composting plants amounted to 6.9 × 10²–2.5 × 10⁴ CFU/m³ in the air, 2.9 × 10²–3.3 × 10³ CFU/100 cm² on surfaces, and 2.2 × 10⁵–2.4 × 10⁷ CFU/g in compost. Qualitative analysis revealed 75 microbial strains in composting plants, with filamentous fungi being the largest group of microorganisms, accounting for as many as 38 isolates. The total amount of endotoxins was 0.0062–0.0140 nmol/mg of dust. The dust fraction with aerodynamic particle diameter of 0.65–1.1 μm accounted for 28–39% of bacterial aerosols and 4–13% of fungal aerosols. We propose the following strains as indicators of harmful biological agent contamination: Bacillus cereus, Aspergillus fumigatus, Cladosporium cladosporioides, C. herbarum, Mucor hiemalis, and Rhizopus oryzae for both types of composting plants, and Bacillus pumilus, Mucor fragilis, Penicillium svalbardense, and P. crustosum for green waste composting plants. The biological hazards posed within these plants are due to the presence of potentially pathogenic microorganisms and the inhalation of respirable bioaerosol. Depending on the type of microorganism, these hazards may be aggravated or reduced after cleaning procedures.

Implications:?This study assessed the microbial contamination in two categories of composting plants: (1) facilities producing substrates for industrial cultivation of button mushrooms, and (2) facilities for processing biodegradable waste. Both workplaces showed potentially pathogenic microorganisms, respirable bioaerosol, and endotoxin. These results are useful to determine the procedures to control harmful biological agents, and to disinfect workplaces in composting plants.     

Particulate matter on two Prunus spp. decreases survival and performance of the folivorous beetle Gonioctena quinquepunctata

Woody plants growing along streets and construction sites play an important role in removing harmful particulate matter (PM). Researchers rarely consider the impact of different types and size fractions of PM deposited on the leaves on insect folivores. We determined differences in the accumulation of cement and roadside PM on the leaves of two Prunus species (P. padus and P. serotina) with different leaf surface structures. We also determined the effect of PM on the beetle Gonioctena quinquepunctata, the main pest of these plants. Saplings were artificially dusted in greenhouses and leaves were utilised for larval and adult insect stages feeding in laboratory conditions. Road PM accumulated in greater amounts than did cement PM, regardless of plant species. For both PM sources, P. padus accumulated twofold more than did P. serotina. Insect survival was negatively affected by PM pollution; however, neither Prunus species nor PM source variant significantly affected masses of larvae and pupae, duration of larval and pupal development or relative growth rates. The experiment showed strong negative influences of PM were noted only for adult insects, due to the grazing period being longer than that in larvae. The mass of adult insects and the efficiency of conversion of ingested food (ECI) were lower for insects exposed to PM than those for control insects. Insects compensated for lower ECI by eating a greater total amount of food (TFE). Adult insects gained significantly higher mass when fed with P. serotina than with P. padus. The effect of PM on analysed plant metabolites was insignificant. Only Prunus sp. and date of collection affected the level of condensed tannins and total phenols. Our results indicate that, when investigating the effect of the host plant on folivore performance, the accumulation of PM, as well as its type and quantity, should be taken into account.

     

Structure,Mechanical, Thermal and Fire Behavior Assessments of Environmentally Friendly Crude Glycerol-Based Rigid Polyisocyanurate Foams

In this work, rigid polyisocyanurate foams were prepared at partial substitution (0–70 wt%) of commercially available petrochemical polyol, with previously synthesized biopolyol based on crude glycerol and castor oil. Influence of the biopolyol content on morphology, chemical structure, static and dynamic mechanical properties, thermal insulation properties, thermal stability and flammability was investigated. Incorporation of 35 wt% of crude glycerol-based polyol had reduced average cell size by more than 30% and slightly increased closed cell content, simultaneously reducing thermal conductivity coefficient of foam by 12% and inhibiting their thermal aging. Applied modifications showed also positive impact on the mechanical performance of rigid foams. Increase of crosslink density resulted in enhancement of compressive strength by more than 100%. Incorporation of prepared biopolyol resulted in enhancement of thermal stability and changes in degradation pathway. Up to 35 wt% share of crude glycerol-based polyol, foams showed similar flammability as reference sample, which can be considered very beneficial from the environmental point of view.     

The use of ALS,botanical, and soil data to monitor the environmental hazards and regeneration capacity of areas devastated by highway construction

The impact of viaduct construction on the vegetation of a river valley was studied in Central Poland (Natura 2000 site PLH100006). The research aimed at assessing the suitability of ALS (airborne laser scanning), soil, and botanical data for monitoring the environmental effects of right-of-way reclamation 1 year after the road construction. Based on the data mentioned above, the following problems were identified: changes in topography and hydrological conditions of the valley as a result of improper land levelling, the use of inadequate soil for reclamation, no spontaneous regeneration of natural vegetation along the entire right-of-way, as well as the abundant occurrence of invasive species. The results of analysis were used to define strategies for mitigation of adverse impacts of the viaduct construction.