Investigation of novel material for effective photodegradation of bezafibrate in aqueous samples

A novel composite with an enhanced photocatalytic activity was prepared and applied to study the removal of bezafibrate (BZF), a hypolypemic pharmaceutical, from an aqueous environment. For the enhancement of titanium dioxide photoactivity a fullerene derivative, 2-(ferrocenyl) fulleropyrrolidine (FcC₆₀), was synthesized and applied. Obtained composite was found to show a higher catalytic activity than pristine TiO₂. Therefore, high hopes are set in composites that are based on carbonaceous nanomaterials and TiO₂ as a new efficient photocatalysts.     

Capsaicin-induced dysregulation of acid-base status in the American cockroach

Abstract

Members of TRP receptor family are involved in response to acidification. Here, we determined the effect of capsaicin, one of the TRP receptor activators, on hemolymph acid-base status in the American cockroach. Periplaneta americana adult individuals were injected with lactic acid (5% or 10%) and exposed to 100?µM capsaicin solution. Hemolymph pH was measured 15?min, 1, 4, 8 and 24?h after lactic acid and capsaicin application with a glass microelectrode. The results demonstrated that cockroaches recover from acidosis within 4?h from acid injection. Capsaicin impaired the buffering capacity of insects’ hemolymph, resulting in significant drop of hemolymph pH observed even 24?h after application. Joint action of capsaicin and acidosis reveals new insight into possible mechanism of capsaicin action on TRP receptors in insects.     

Application of different chromatographic techniques and chemometric analysis in authenticity testing of plant protection products containing azoxystrobin as an active substance

Azoxystrobin (methyl(2E)-2-{2-[6-(2-cyanophenoxy)pyrimidin-4-yloxy] phenyl}-3-methoxyacrylate) is an active ingredient used to protect crops against fungal diseases. The experience of the Polish control laboratory indicates relatively frequent cases of counterfeit plant protection products (PPPs) containing this active substance. The present study aimed to use chemometric methods to model chemical fingerprints obtained by different chromatographic techniques to verify the original formulation of PPPs containing the active substance azoxystrobin. The pesticides used in the study came from different sources (including stores and warehouses), were manufactured at a different time and came from different production batches. The results obtained with the HPLC-DAD and HS-GC-MS techniques were then modeled using principal component analysis (PCA) and soft independent modeling by class analogy (SIMCA) classifier. The proposed approach has been confirmed as useful for verifying the authenticity of PPPs and can be used in the routine control testing of SC pesticides containing azoxystrobin.     

Kelp as a Bioindicator: Does it Matter Which Part of 5 M Long Plant is Used for Metal Analysis?

Kelp may be useful as a bioindicator because they are primary producers that are eaten by higher trophic level organisms, including people and livestock. Often when kelp or other algae species are used as bioindicators, the whole organism is homogenized. However, some kelp can be over 25 m long from their holdfast to the tip of the blade, making it important to understand how contaminant levels vary throughout the plant. We compared the levels of arsenic, cadmium, chromium, lead, manganese, mercury and selenium in five different parts of the kelp Alaria nana to examine the variability of metal distribution. To be useful as a bioindicator, it is critical to know whether levels are constant throughout the kelp, or which part is the highest accumulator. Kelp were collected on Adak Island in the Aleutian Chain of Alaska from the Adak Harbor and Clam Cove, which opens onto the Bering Sea. In addition to determining if the levels differ in different parts of the kelp, we wanted to determine whether there were locational or size-related differences. Regression models indicated that between 14% and 43% of the variation in the levels of arsenic, cadmium, chromium, manganese, mercury, and selenium was explained by total length, part of the plant, and location (but not for lead). The main contributors to variability were length (for arsenic and selenium), location (mercury), and part of the plant (for arsenic, cadmium, chromium and manganese). The higher levels of selenium occurred at Clam Cove, while mercury was higher at the harbor. Where there was a significant difference among parts, the holdfast had the highest levels, although the differences were not great. These data indicate that consistency should be applied in selecting the part of kelp (and the length) to be used as a bioindicator. While any part of Alaria could be collected for some metals, for arsenic, cadmium, chromium, and manganese a conversion should be made among parts. In the Aleutians the holdfast can be perennial while the blade, whipped to pieces by winter wave action, is regrown each year. Thus the holdfast may be used for longer-term exposure for arsenic, cadmium, chromium and manganese, while the blade can be used for short-term exposure for all metals. Cadmium, lead and selenium were at levels that suggest that predators, including people, may be at risk from consuming Alaria. More attention should be devoted to heavy metal levels in kelp and other algae from Adak, particularly where they may play a role in a subsistence diets.     

Radionuclide Concentrations in Benthic Invertebrates from Amchitka and Kiska Islands in the Aleutian Chain, Alaska

Concentrations of 13 radionuclides (¹³⁷Cs, ¹²⁹I, ⁶⁰Co, ¹⁵²Eu, ⁹⁰Sr, ⁹⁹Tc, ²⁴¹Am, ²³⁸Pu, ^239,249Pu, ²³⁴U, ²³⁵U, ²³⁶U, ²³⁸U were examined in seven species of invertebrates from Amchitka and Kiska Islands, in the Aleutian Chain of Alaska, using gamma spectroscopy, inductively coupled plasma mass spectroscopy, and alpha spectroscopy. Amchitka Island was the site of three underground nuclear test (1965–1971), and we tested the null hypotheses that there were no differences in radionuclide concentrations between Amchitka and the reference site (Kiska) and there were no differences among species. The only radionuclides where composite samples were above the Minimum Detectable Activity (MDA) were ¹³⁷Cs, ²⁴¹Am, ^239,249Pu, ²³⁴U, ²³⁵U, ²³⁶U, and ²³⁸U. Green sea urchin (Strongylocentrotus polyacanthus), giant chiton (Cryptochiton stelleri), plate limpets (Tectura scutum) and giant Pacific octopus (Enteroctopus dofleini) were only tested for ¹³⁷Cs; octopus was the only species with detectable levels of ¹³⁷Cs (0.262 ± 0.029 Bq/kg, wet weight). Only rock jingle (Pododesmus macroschisma), blue mussel (Mytilus trossulus) and horse mussel (Modiolus modiolus) were analyzed for the actinides. There were no interspecific differences in ²⁴¹Am and ^239,240Pu, and almost no samples above the MDA for ²³⁸Pu and ²³⁶U. Horse mussels had significantly higher concentrations of ²³⁴U (0.844 ± 0.804 Bq/kg) and ²³⁸U (0.730 ± 0.646) than the other species (both isotopes are naturally occurring). There were no differences in actinide concentrations between Amchitka and Kiska. In general, radionuclides in invertebrates from Amchitka were similar to those from uncontaminated sites in the Northern Hemisphere, and below those from the contaminated Irish Sea. There is a clear research need for authors to report the concentrations of radionuclides by species, rather than simply as ‘shellfish’, for comparative purposes in determining geographical patterns, understanding possible effects, and for estimating risk to humans from consuming different biota.     

Characterization of PM10 and PM2.5 and associated heavy metals at the crossroads and urban background site in Zabrze, Upper Silesia, Poland, during the smog episodes

The concentrations of seven heavy metals (Cd, Cr, Cu, Fe, Mn, Ni, and Pb) associated with PM10 and PM2.5 at the crossroads and the background sites have been studied in Zabrze, Poland, during smog episodes. Although the background level was unusually elevated due to both high particulate emission from the industrial and municipal sources and smog favorable meteorological conditions, significant increase of the concentration of PM2.5 and PM10 as well as associated heavy metals in the roadside air compared to the urban background has been documented. The average daily difference between the roadside and corresponding urban background aerosol concentration was equal to 39.5 μg m^???3 for PM10 and 41.2 μg m^???3 for PM2.5. The highest levels of the studied metals in Zabrze appeared for iron carried by PM10 particles: 1,706 (background) and 28,557 ng m^???3 (crossroads). The lowest concentration level (in PM10) has been found for cadmium: 7 and 77 ng m^???3 in the background and crossroads site, respectively. Also the concentrations of heavy metals carried by the fine particles (PM2.5) were very high in Zabrze during the smog episodes. Concentrations of all studied metals associated with PM10 increased at the roadside compared to the background about ten times (one order) while metals contained in PM2.5 showed two to three times elevated concentrations (except Fe—five times and Cr—no increase).     

The impact of land use and season on the riverine transport of mercury into the marine coastal zone

In Mediterranean seas and coastal zones, rivers can be the main source of mercury (Hg). Catchment management therefore affects the load of Hg reaching the sea with surface runoff. The major freshwater inflows to the Baltic Sea consist of large rivers. However, their systems are complex and identification of factors affecting the outflow of Hg from its catchments is difficult. For this reason, a study into the impact of watershed land use and season on mercury biogeochemistry and transport in rivers was performed along two small rivers which may be considered typical of the southern Baltic region. Neither of these rivers are currently impacted by industrial effluents, thus allowing assessment of the influence of catchment terrain and season on Hg geochemistry. The study was performed between June 2008 and May 2009 at 13 sampling points situated at different terrain types within the catchments (forest, wetland, agriculture and urban). Hg analyses were conducted by CVAFS. Arable land erosion was found to be an important source of Hg to the aquatic system, similar to urban areas. Furthermore, inflows of untreated storm water discharge resulted in a fivefold increase of Hg concentration in the rivers. The highest Hg concentration in the urban runoff was observed with the greatest amount of precipitation during summer. Moderate rainfalls enhance the inflow of bioavailable dissolved mercury into water bodies. Despite the lack of industrial effluents entering the rivers directly, the sub-catchments with anthropogenic land use were important sources of Hg in the rivers. This was caused by elution of metal, deposited in soils over the past decades, into the rivers. The obtained results are especially important in the light of recent environmental conscience regulations, enforcing the decrease of pollution by Baltic countries.     

Aerosol residence times and changes in radioiodine-131I and radiocaesium-137 Cs activity over Central Poland after the Fukushima-Daiichi Nuclear reactor accident

The first detectable activities of radioiodine (131)I, and radiocaesium (134)Cs and (137)Cs in the air over Central Poland were measured in dust samples collected by the ASS-500 station in the period of 21(st) to 24(th) of March, 2011. However, the highest activity of both fission products, (131)I and (137)Cs: 8.3 mBq m(-3) and 0.75 mBq m(-3), respectively, were obtained in the samples collected on 30(th) March, i.e.～18 days after the beginning of the fission products' discharge from the damaged units of the Fukushima Daiichi Nuclear Power Plant. The simultaneously determined corrected aerosol residence time for the same samples by (210)Pb/(210)Bi and (210)Pb/(210)Po methods was equal to 10 days. Additionally, on the basis of the activity ratio of two other natural cosmogenic radionuclides, (7)Be and (22)Na in these aerosol samples, it was possible to estimate the aerosol residence time at ～150 days for the solid particles coming from the stratospheric fallout. These data, as well as the differences in the activity size distribution of (7)Be and (131)I in the air particulate matter, show, in contrast to the Chernobyl discharge, a negligible input of stratospheric transport of Fukushima-released fission products.     

Attitudes and Perceptions about Ecological Resources, Hazards, and Future Land Use of People Living near the Idaho National Engineering and Environmental Laboratory

This paper examines the attitudes and perceptions of local people about ecological resources, environmental hazards, and future land use of the Idaho National Engineering and Environmental Laboratory (INEEL). Such monitoring of attitudes is an important aspect of environmental assessment. We interviewed 262 people who attended the 42nd Annual Free Fishermen's Breakfast at St. Anthony, Idaho, on 23 March 1997. We tested the null hypotheses that there were no differences in perceptions about ecological resources, hazards and future land use of INEEL as a function of gender, age, education, and place of residence. Dumping trash in the ocean and cutting rainforests rated as the environmental problems of highest concern, and ozone, radon and high voltage lines rated the lowest; cleaning up Department of Energy sites rated intermediate. Respondents were most willing to expend government funds to make drinking water clean. Three significant differences were found: 1) women rated environmental problems as more severe than did men, and women were more willing to expend federal funds to solve these problems, 2) respondents under 30 years of age rated environmental problems as more severe than older people, and they were more willing to spend money to solve them, and, 3) respondents who had not finished high school were more concerned with environmental problems and were more willing to spend money to solve them than respondents with a high school education. Maintaining INEEL as a National Environmental Research Park (NERP) rated as the most preferred future land use, followed by continued reprocessing of nuclear materials and hunting. Using INEEL for housing and additional nuclear waste storage rated the lowest. Men rated grazing livestock and additional nuclear waste storage higher than did women. In general, respondents from 30 – 49 rated several economic uses (hunting, grazing livestock, growing crops) higher than did people in other age groups. Respondents with some college rated these economic uses higher than did respondents who had not graduated from high school. These results indicate that respondents living around INEEL believe that INEEL should continue with a reprocessing and NERP mission, but that other peripheral uses, such as hunting, hiking and grazing, should be allowed on some of the land. These views should aid in environmental assessment of the site, and in developing further management plans for INEEL.     

Remediation aspect of microbial changes of plant rhizosphere in mercury contaminated soil

Phytoremediation, an approach that uses plants to remediate contaminated soil through degradation, stabilization or accumulation, may provide an efficient solution to some mercury contamination problems. This paper presents growth chamber experiments that tested the ability of plant species to stabilize mercury in soil. Several indigenous herbaceous species and Salix viminalis were grown in soil collected from a mercury-contaminated site in southern Poland. The uptake and distribution of mercury by these plants were investigated, and the growth and vitality of the plants through a part of one vegetative cycle were assessed. The highest concentrations of mercury were found at the roots, but translocation to the aerial part also occurred. Most of the plant species tested displayed good growth on mercury contaminated soil and sustained a rich microbial population in the rhizosphere. The microbial populations of root-free soil and rhizosphere soil from all species were also examined. An inverse correlation between the number of sulfur amino acid decomposing bacteria and root mercury content was observed. These results indicate the potential for using some species of plants to treat mercury contaminated soil through stabilization rather than extraction. The present investigation proposes a practical cost-effective temporary solution for phytostabilization of soil with moderate mercury contamination as well as the basis for plant selection.