The degradation of the cyanobacterial hepatotoxin nodularin (NOD) by UV radiation

This study investigates the decomposition of NOD by UV irradiation. Water solutions of pure NOD and NOD-containing Nodularia extract as well as Nodularia filaments collected on filters were exposed to UV-A, UV-B, and white fluorescent light (VIS) during 48 h experiments. In VIS, the toxin was fairly stable and only 3.8-4.6% of the original degraded. UV-B had the most pronounced effect on the NOD degradation rate. In the experiment, the overall loss of NOD was 0.27 and 0.77 micro g ml(-1)day(-1) for the solution of pure toxin and Nodularia extract and 0.28 micro g day(-1) for Nodularia filaments. Comparison of UV-B degradation rate in water and methanol extracts revealed higher stability of NOD in methanol. This might suggest that some hydrophobic components of Nodularia cell play a protective role against UV radiation. Additionally, chemical (LC-MS/MS) and biochemical (ELISA and PPIA) assays were employed to characterize the UV degradation products. LC-MS/MS analyses showed that in UV-B exposed sample, apart from NOD, there were three other compounds with molecular ion at m/z at 825.4. The fragmentation pattern of the ion was the same for all four compounds suggesting that they are geometrical isomers of NOD. The major degradation product, with a local absorption maximum at 242 nm, was active in both biochemical assays.     

Lessons from Norovirus Outbreak in Warsaw,Poland, December 2012

Efficient foodborne outbreak investigations are important for identification of gaps in food safety and public health practice. This article reports on an investigation of a gastroenteritis outbreak linked to catering food following a Christmas reception at the National Institute of Public Health-National Institute of Hygiene (NIPH-NIH) in Warsaw in December 2012. Of 192 employees eating food at the catering event, 97 (50.5 %) developed symptoms. Persons eating dishes with recipes containing frozen carrots were five times more likely to develop gastrointestinal symptoms compared to those who did not eat carrots. Laboratory analysis identified norovirus in stool samples taken from symptomatic persons. Leftover food was not available for testing. The investigators did not collect stool specimens from food handlers and did not conduct trace backs for the suspected food ingredients. This investigation underlines the need for a revision of an existing procedures and importance of their complementation with detailed instructions for the local public health authorities for effective completion of foodborne outbreaks investigations in Poland.     

Occurrence of Norovirus and Hepatitis A Virus in Wild Mussels Collected from the Baltic Sea

The aim of the study was to define the occurrence of human noroviruses of genogroup I and II (NoV GI and NoV GII) and hepatitis A virus (HAV) in the Baltic Sea mussels. The shellfish samples were taken at the sampling sites located on the Polish coast. In total, 120 shellfish were tested as pooled samples using RT-PCR and hybridisation with virus specific probes. NoV GI was detected in 22 (18.3 %), NoV GII in 28 (23.3 %), and HAV in 9 (7.5 %) of the shellfish. The nucleotide sequence analysis of the detected NoV GII strains showed a 97.3–99.3 % similarity to GII.4 virus strain. This is the first report describing the NoV and HAV occurrence in wild Baltic mussels and their possible role as bioindicators of seawater contamination with human enteric viruses.     

An evaluation of selected chemical,biochemical, and biological parameters of soil enriched with vermicompost

Environmental Science and Pollution Research - The aim of this study was to assess the changes in chemical and microbial properties and enzymatic activity of soil enriched with vermicompost derived...     

Distribution of ozone and other air pollutants in forests of the Carpathian Mountains in central Europe.

Ozone (O3) concentrations were monitored during the 1997-1999 growing seasons in 32 forest sites of the Carpathian Mountains. At all sites (elevation between 450 and 1320 m) concentrations of O3, nitrogen dioxide (NO2), and sulfur dioxide (SO2) were measured with passive samplers. In addition, in two western Carpathian locations, Vychodna and Gubalówka, ozone was continuously monitored with ultraviolet (UV) absorption monitors. Highest average hourly O3 concentrations in the Vychodna and Guba?ówka sites reached 160 and 200 microg/m3 (82 and 102 ppb), respectively (except for the AOT40 values, ozone concentrations are presented as microg/m3; and at 25 degrees C and 760 mm Hg, 1 microg O3/m3 = 0.51 ppb O3). These sites showed drastically different patterns of diurnal 03 distribution, one with clearly defined peaks in the afternoon and lowest values in the morning, the other with flat patterns during the entire 24-h period. On two elevational transects, no effect of elevation on O3 levels was seen on the first one, while on the other a significant increase of O3 levels with elevation occurred. Concentrations of O3 determined with passive samplers were significantly different between individual monitoring years, monitoring periods, and geographic location of the monitoring sites. Results of passive sampler monitoring showed that high O3 concentrations could be expected in many parts of the Carpathian range, especially in its western part, but also in the eastern and southern ranges. More than four-fold denser network of monitoring sites is required for reliable estimates of O3 distribution in forests over the entire Carpathian range (140 points). Potential phytotoxic effects of O3 on forest trees and understory vegetation are expected on almost the entire territory of the Carpathian Mountains. This assumption is based on estimates of the AOT40 indices for forest trees and natural vegetation. Concentrations of NO2 and SO2 in the entire Carpathian range were typical for this part of Europe and below the expected levels of phytotoxicity.     

Study on degradation process of famotidine hydrochloride in aqueous samples

The kinetics of famotidine (FAM) transformation under the influence of various factors, important from the environmental point of view, was investigated in aqueous solutions. The degradation processes using UV, H₂O₂, UV/H₂O₂, H₂O₂/Fe²⁺, and UV/H₂O₂/Fe²⁺ were studied. Direct photolysis and H₂O₂-assisted photolysis showed a pseudo-first-order kinetics, while the Fenton and the photo-Fenton processes fit second-order kinetics. The provided experiments proved a high resistance of FAM to direct photolysis. Its stability depends highly on the pH of the reaction solutions. The rate of FAM direct photolysis in acidic solutions was almost negligible. The reaction rate of FAM photolysis at pH 8–9 was 3.7 × 10^?3 min^?1 with DT₅₀ about 3 h 7 min. It was found that the presence of H₂O₂ in the reaction environment enhances the rate of photolysis of FAM. The observed rates of reaction were 5.1 × 10^?3 min^?1 and 3.7 × 10^?3 min^?1 in acidic and basic solutions, respectively. The used Fenton systems appeared to be the most efficient in FAM removal. The rate of reaction depends on concentration of Fe²⁺ and H₂O₂. It was observed that the presence of UV-light enhances the reaction rate by two to six times in comparison to the classical Fenton system. Additionally, FAM behavior in natural water under solar irradiation was examined. The irradiation experiments were carried out in batch experiments with simulated sunlight.     

A new derivatization method for a determination of MX and related hydroxyfuranones in water

An extremely potent mutagen, 3‐chloro‐4(dichloromethyl)‐5‐hydroxy‐2(5/f)‐furanone (MX) is commonly present in chlorinated drinking water. Due to its high mutagenic activity and according to WHO guidelines its concentration should be controlled in drinking waters. Determination of MX is difficult due to ppt levels at which the compound usually exists in drinking waters. Derivatization with 2‐propanol is presented as a method which significantly lowers GC/MS detection level of MX. Suitability of 2‐propylation for derivatization of other hydroxyfuranones is also shown.     

Workaholism and mental health among Polish academic workers

The aim of this study was to examine the relationship between workaholism and mental health among 126 Polish academic workers. The participants' mean age was 45.9 years, 51.6% of them were women. The participants completed 2 questionnaires: the work addiction risk test and the general health questionnaire. Even though 66% of the subjects were classified in the group of moderate-to-high risk of workaholism, the overall state of mental health was categorized as average. The results revealed that workaholism was associated with poorer mental health. Employees with higher levels of workaholism had worse state of health, i.e., more somatic symptoms, higher levels of anxiety, insomnia, social dysfunction and symptoms of depression. Emotional arousal/perfectionism was the strongest predictor of the state of general health and was mostly responsible for harmful effects on mental health. However, the general effect of workaholism on health was not as strong as expected.     

Measuring coupling forces woodcutters exert on saws in real working conditions

Prolonged exposure to hand-arm vibration (HAV) generated by chainsaws can cause HAV syndrome, i.e., disorders in the upper extremities of forestry workers. Progress of HAV syndrome depends on the intensity of mechanical vibration transmitted throughout the body, which is directly proportional to coupling forces applied by the woodcutter to a vibrating tool. This study aimed to establish a method of measuring coupling forces exerted by chainsaw workers in real working conditions. Coupling forces exerted by workers with their right and left hands were measured with a hydro-electronic force meter. Wood hardness, the type of chainsaw and the kind of forest operation, i.e., felling, cross-cutting or limbing, were considered.