No abstract

Abstract:The study aims at evaluating whether webs reflect the level of air pollution measured with conventional methods. Webs of species Malthonica silvestris (l. KOCH, 1872) (Araneae: Agelenidae) were sampled. Samples were analyzed for heavy metals (Pb, Zn) content. According webs analyses and classic measurements three traffic -oriented sites in Wroclaw (South-West Poland) showed significantly higher mean concentrations of heavy metals than two other sites situated in quieter, low traffic areas. A very strong significant positive correlation was revealed among average concentrations of Zn and Pb associated with fine particulate matter of atmospheric aerosol (PM1) and webs. We also observed a very strong significant positive correlation among Zn and Pb concentrations on webs and PM2.5. Any significant correlation among PM-emission fractions 2.5 and 10 and associated heavy metals and dust deposited on spider webs was not observed. Although spider webs proved useful indicators of environmental pollution the obtained results suggest that this tool should be used to evaluate the emission of heavy metals in the similar way as other bioindicators such as mosses and lichens are commonly used. The measured concentrations on webs do not reflect results obtained with classic methods. We conclude that spider webs are good for bioindication of road traffic emissions, they could be even more reliable compared to use of some other bioindicators whose activity is often limited by the lack of water and sun.

Crocker Nuclear Laboratory uses a custom built energydispersive X-ray fluorescence system with a molybdenum anode to provide routine analysis of elements from nickel to zirconium and lead in Interagency Monitoring of Protected Visual Environments (IMPROVE) samples. Standard methods are used to ensure accuracy and statistical control of the data, including repeated analysis of singleelement standards, standard reference materials, and selected actual samples from the IMPROVE network. This paper compares the short-term (week) precision and longterm (2-yr) reproducibility revealed by the actual sample reanalyses. Currently reported analytical uncertainties are shown to predict actual 2-yr reproducibility within a factor of 2.

No abstract

Transportation is widely recognized to be a significant and increasing source of air pollution. In the city of Chillán there are many public cars, buses and trucks that have been retired from circulation in the metropolitan region (capital city of Santiago) due to strict regulation from local environmental authorities. In order to study air pollution in Chillán, a typical semi-agricultural central valley city located in the southern Bio-Bio Region of Chile, an aerosol monitoring study was established to measure ambient aerosol composition. The contributions of private cars, public cars, buses and delivery trucks were examined at a sampling site located downtown. The aerosol monitor was operated from September 2001 to September 2002. The study employed an IMPROVE PM 10 sampler with Anderson inlet at 3 meters above ground collecting PM 10 on Teflon membrane filter, nylon and quartz filter.Sulfate concentrations were lower than soil, nitrate, elemental and organic carbon, which contributed significantly to PM 10 mass. Soil accounted for 25% of the PM 10 mass and carbon particles accounted for just over 50%. Transportation sources appear to be primary sources of the carbon and soil particles. The remaining mass was mostly secondary ammonium nitrate and ammonium sulfate. Some metals, such as V, Ni, Br, and Pb, were measured frequently at the downtown site. They did not contribute appreciably to the PM 10 mass, but underscore the importance of transportation sources to measured particulate matter.