Urbanization and the rise in the standard of living generated both a higher quantity of waste and the expansion of cities with the incorporation of solid waste landfills located originally outside. In many cities across Romania, landfills are placed very close to settlements, and in some cases even inside cities. Beside landfill activities, other companies that deal with waste sorting, recycling and treatment operates nearby. All these activities generate odorous compounds that create odour nuisance. The current study was conducted in order to evaluate the impact of a landfill located in a highly urbanized area using dynamic olfactometry with the main objective to assess the level of odour concentration and the impact on the population. Samples were taken around the landfill always from a point opposite to the wind direction. Also, in parallel with odour sampling it was determined the concentration of two main chemical specific compounds, NH3 and H2S, in order to verify the compliance with environmental legislation, and the level of VOC to establish a correlation with the odour level. Measurement results indicate a high level of odour concentration in most of the samples, a good correlation with VOC and frequent exceeded values for the specific chemical compounds. Annoyance level was also high and it was evaluated using FIDOL factors, which are Frequency, Intensity, Duration, Offensiveness and Location.

The effectiveness of some chemical matrix modifiers for the determination of lead, chromium, selenium and arsenic in sediments and soils by Zeeman electrothermal atomic absorption spectrometry have been evaluated. The addition of certain chemical modifiers decreases the volatility of the analyte element, preventing its loss during pyrolysis step while increasing the volatility of matrix components promoting a better separation also allows a higher pretreatment temperature for better separation between analyte and matrix. Pyrolysis and atomization temperatures, characteristic masses and detection limits of analytes in dissolved samples with and without modifiers have been compared. The method was validated by analysing certified reference lake sediment and soil materials.

In the present paper we report, a series of experimental characterization and analysis models that can be applied to industrial waste samples in order to determine the heavy metals within them. During our studies we determined that both preparation and pretreatment of the waste sample are the two most important steps in the analysis process. Therefore, an increased attention was given in using appropriate procedures and methods for preparation and pretreatment. In order to ensure a correct and secure analysis were developed experimental models based on preparation and pretreatment stages and also on organic matrix decomposition method (digestion process with acid mixture under microwave). These experimental models were tested on a series of wastes coming from processing and finishing activities of metal surfaces and other materials. Metal concentration was analyzed by AAS (atomic absorption spectrometry) and XRF (X-ray fluorescence spectrometry). The obtained results proved that the proposed experimental models are suitable for analysis of different types of industrial wastes samples.

Some natural adsorbents were evaluated for the advanced removal of pollutants from aqueous systems. The sorption capacity of walnut shells and volcanic zeolite tuff (from Mirsid-Cluj Romania) to remove the chrome and cadmium at different experimental conditions was studied. The concentration of metal ions in aqueous systems was evaluated with an inductively coupled plasma mass spectrometer (ICP-MS) and an atomic absorption spectrometer. The effect of time, initial concentration of the metals and solution pH on the adsorption at room temperature was studied. pH of the solutions was found to influence the adsorption. Higher Cr(VI) adsorption was observed at lower pH and at low concentration of metal ions. The maximum efficiency of volcanic tuff in acidic media was 97.12% for chrome and 57.04% for cadmium, respectively, for 0.1 mg/L initial concentration. Moreover, in the same experimental conditions, the maximum efficiency of walnut shells was 61.24% and 44.51% for chrome and cadmium. The two low-cost natural sorbents were efficient for the remove of pollutants from aqueous systems.