A Contribution to the Study of the Antidust Respirators’ Real Performance

In most industrial enterprises, hazardous factors are present in quantities exceeding permissible levels. Such a situation requires using antidust respiratory protection. It has been suggested, however, that filters for respirators are not assessed properly and that lab results might not be related to real filtering efficiency in industry. This article contains test results of some commercially available filtering half-masks, including the effect of loading with real dust, high humidity, high temperature, and a combination of loading with dust and high humidity on the half-masks’ performance. The results show that the effect of these factors is considerable and that a combination of loading with silica dust and exposing to high humidity can cause a complete loss of performance.     

Environmentally friendly assessment of organic compound bioaccessibility using sub-critical water

The evaluation of microbial availability of contaminants is of high importance for better reflecting the processes governing contaminant fate in soil and for establishing the risk associated with contaminated sites. A sub-critical water extraction technique was assessed for its potential to determine the microbially degradable fraction of [¹⁴C]phenanthrene-associated activity in two dissimilar soils at three different ageing times (14, 28 and 49 days). For the majority of determinations, no significant (p > 0.05) difference between sub-critical water-extracted ¹⁴C-activity at 160 °C and the fraction mineralized by catabolically active Pseudomonas sp. was observed. Collectively, the results suggested that the sub-critical water extraction technique was an appropriate technique for predicting the biodegradable fraction of phenanthrene-associated ¹⁴C-activity in dissimilar soils following increasing soil-contaminant contact time.     

Assessment of waste management technology using BATNEEC options, technology quality method and multi-criteria analysis

Best Available Techniques Not Entailing Excessive Costs (BATNEEC) options, technology quality method and multi-criteria analysis were proposed as means of developing indices for evaluating municipal waste management systems. The proposed indices can be treated as a tool for ranking the system taking into account technical, environmental, economic, social and other objectives, bearing in mind specific features of the area involved. The analysis was made for three different incineration plants (Spittelau in Vienna, Warsaw and Tarnobrzeg) together with alternative waste disposal versions (with or without biogas burning and with MBP Mechanical-Biological Process) and the waste management infrastructure. The results showed that incineration of waste is much more beneficial than disposal. These results conform to the waste hierarchy identified in EU Directive 2008/98, but the indices created are easy to interpret and useful as a tool for communicating with the public, which is often a crucial factor in determining the location of investment.     

Betaine removal during thermo- and mesophilic aerobic batch biodegradation of beet molasses vinasse: influence of temperature and pH on the progress and efficiency of the process

The key issue in achieving a high extent of biodegradation of beet molasses vinasse is to establish the conditions for the assimilation of betaine, which is the main pollutant in this high-strength industrial effluent. In the present study, aerobic batch biodegradation was conducted over the temperature range of 27-63°C (step 9°C), at a pH of 6.5 and 8.0, using a mixed culture of bacteria of the genus Bacillus. Betaine was assimilated at 27-54°C and the pH of 8.0, as well as at 27-45°C and the pH of 6.5. The processes where betaine was assimilated produced a high BOD(5) removal, which exceeded 99.40% over the temperature range of 27-45°C at the pH of 8.0, as well as at 27°C and the pH of 6.5. Maximal COD removal (88.73%) was attained at 36°C and the pH of 6.5. The results indicate that the process can be applied on an industrial scale as the first step in the treatment of beet molasses vinasse.     

Influence of anthropogenic transformations of river bed on plant and macrozoobenthos communities

This study describes the influence of urban area on plant communities and benthic invertebrates inhabiting the S?upia River (northern Poland). Ten plant communities and 37 macrozoobenthos taxa were determined during four seasonal samplings at 25 sampling sites (October 2005 and January, April, and August 2006). The obtained data set was statistically evaluated in order to reveal the influence of anthropogenic transformations on the investigated communities against the background of other abiotic factors. Multivariate regression tree (MRT) method was used for vegetation, while for benthic fauna, both MRT and artificial neural network (ANN) methods were applied. The following explanatory variables were used: season, water temperature, and salinity; location of a sampling site; degree of human impact on the riverbed; microhabitat; and substrate type. MRT analyses showed significant differences in plant community structure depending on the location of a sampling site, indicating the influence of anthropogenic pressure, while macrozoobenthos composition differed significantly only between seasons. The overall ANN model proved the importance of type and location of a sampling site for the approximation of benthic fauna density. Additionally, influence of the explanatory variables on the consecutive macrozoobenthos taxa was analyzed on the basis of separate ANN.     

Biodegradation of poly(propylene glycol)s under the conditions of the OECD screening test

Two poly(propylene glycol)s (PPGs): PPG 425 and PPG 725 were tested under the conditions of the OECD Screening Test with activated sludge as inoculum. Tested PPG were the sole source of organic carbon in the test. Quantitative determination of the biodegradation progress was performed by the HPLC with fluorescence detection after derivatisation of PPG with naphthyl isocyanate. The liquid chromatography-mass spectrometry technique was used for identification and semiquantitative determination of metabolites. Separation of PPG and metabolites from the water matrix was performed by liquid-liquid extraction with chloroform. It was found that the shorter PPG 425 is biodegraded significantly worse than the longer PPG 725 and that biodegradation occurs without shortening of the PPG chain for both PPG. PPG molecules are oxidised to ketones and/or aldehydes during the aerobic biodegradation process.     

An ergonomics study on wrist posture when using laparoscopic tools in four techniques in minimally invasive surgery

Purpose. With reference to four minimally invasive surgery (MIS) cholecystectomies, the aims were (a) to recognize the factors influencing dominant wrist postures manifested by the surgeon; (b) to detect risk factors involved in maintaining deviated wrist postures; (c) to compare the wrist postures of surgeons while using laparoscopic tools. Methods. Video films were recorded during live surgeries. The films were synchronized with wrist joint angles obtained from wireless electrogoniometers placed on the surgeon's hand. The analysis was conducted for five laparoscopic tools used during all surgical techniques. Results. The most common wrist posture was extension. In the case of one laparoscopic tool, the mean values defining extended wrist posture were distinct in all four surgical techniques. For one type of surgical technique, considered the most beneficial for patients, more extreme postures were noticed regarding all laparoscopic tools. We recognized a new factor, apart from the tool's handle design, that influences extreme and deviated wrist postures. It involves three areas of task specification including the type of action, type of motion patterns and motion dynamism. Conclusions. The outcomes proved that the surgical technique which is best for the patient imposes the greatest strain on the surgeon's wrist.?     

The applicability of compost,zeolite and calcium oxide in assisted remediation of acidic soil contaminated with Cr(III) and Cr(VI)

Environmental Science and Pollution Research - The effect of soil amendments, i.e., compost, zeolite, and calcium oxide, on the chemical properties of soil contaminated with Cr(III) and Cr(VI) and...     

Estimation of external gamma radiation dose in the area of Bory Stobrawskie forests (PL)

The study assessed the radiological risks associated with the presence of natural and artificial radionuclides in the Bory Stobrawskie forests (PL). Using the conversion factors given by UNSCEAR and the measurements results of (232)Th series, (238)U series, (40)K, and (137)Cs specific activities in the 10-cm soil layer the values of absorbed dose (D) and the annual effective dose equivalent derived from terrestrial gamma radiation (E) were calculated. The calculated dose was compared with doses directly measured on the area studied.