Consumer exposure to pesticide residues in apples from the region of south-eastern Poland

The production of apples in Poland is the largest among the countries of the European Union, and therefore, the consumption of these fruits is high in our country. The aim of this study was to determine the presence of pesticide residues in Polish apples and to assess if these residues pose a risk to the health of the consumer. Furthermore, compliance with legal regulations concerning the use of plant protection products in crop cultivation was ascertained. Pesticide residues were found in 192 samples (61.5 % of tested samples). In six samples (1.9 %), residues exceeded maximum residue limits. Violations concerned the insecticides: indoxacarb, diazinon and fenitrothion. The highest long-term consumer exposure was found in the case of consumption of apples with diazinon residue for both groups, adults and toddlers [4 % acceptable daily intake (ADI), adults; 21 % ADI, toddlers]. The highest values of short-term exposure were obtained in the case of consumption of apples with indoxacarb [5 % acute reference dose (ARfD), adults; 27 % ARfD, toddlers] and fenitrothion (4 % ARfD, adults; 23 % ARfD, toddlers). Although fungicides are the pesticides found most often in apples, the consumption of apples with insecticide residues constitutes the greatest hazard to human health.     

A method of rapid identification of the most important ecological problems in polluted areas

A comprehensive method is presented for the evaluation of the living elements of the environment by way of an example of an area situated within the emission range of a non ferrous metal works. The exposure of particular components of the environment is shown using the method of indices, taking into consideration the action of pollutants on the most essential and sensitive receptors. Methods of exposure reduction are also suggested. The proposed method may be helpful in land-use planning in polluted environments and can also be applied to determine the sequence of activities aimed at diminishing the effects of pollution.     

The combined influence of SO2 and heavy metal-containing particulates on beans,carrots and parsley

The effects of various concentrations of air pollutants on crop losses were investigated. Parsley, bean and carrots were fumigated using SO₂ in concentrations ranging from 0.35 mg m^-3 (0.13 ppm) to 4.5 mg m^-3 (1.7 ppm) with and without lead/zinc/cadmium-containing particulate matter. It was concluded that a long-term exposure to low levels of SO₂, even without visible plant injuries, resulted in more significant crop losses than short-term, high concentrations.Measurements of root and leaf weight in carrot and parsley fumigated in exposure chambers with SO₂ show that the ratio of root to leaf weight is dependent on the type and concentration of pollutants. This result leads to the conclusion that a mathematical model describing the above phenomena might be an useful tool in the assessment of crop losses due to known concentrations of air pollutants during the growth period.     

Comparison of ordinary and lognormal kriging on skewed data of total cadmium in forest soils of Sweden

Spatial statistical analysis of georeferenced data of total cadmium (TCd) in forest soils of Sweden was assumed to providemore advantageous maps than traditional interpolated maps. However, 264 measurements of TCd in O-horizon of forest soils displayed skewed frequency distribution. Since atypicalobservations affect badly the variogram, outliers wereidentified, different data transformations were tested andordinary (OK) and lognormal kriging (LK) scenarios werecompared based on cross-validation. Results were comparedusing overall measures of predictors, e.g. traditionalmean squared prediction error (MSPE), mean of krigingvariances, variance ratio, median of internallystandardised residuals, and assessments of classificationaccuracy, such as percentage of correctly predictedsamples and within-class MSPE.One outlier was identified based on the absolute value of skewness of value differences less or equal to one in data pairs separated at certain lag classes. Mapping categories characterised by percentage of correct classification and within-class MSPE were found to be essential in comparison of kriging results additionally to the overall measures. In comparison of kriging methods, OK predicted high values moreaccurately and LK was more effective to predict low and mediumvalues. Thus, OK was suggested for mapping high concentration of TCd and other pollutants. Percentage of correctly predictedsamples and within-class MSPE were found to be dependent on kriging method, as well as on the number and limits of categories.     

Effect of chlorides and sulfates on the performance of a Fe3+/H2O2 Fenton-like system in the degradation of methyl tert-butyl ether and its byproducts.

The effect of chloride and sulfate ions on the oxidation of methyl tert-butyl ether (MTBE) and its degradation products in a Fenton-like system was studied. Although both chloride and sulfate ions inhibited the decomposition of H202, chlorides were found to be the more effective inhibitor of MTBE degradation. In the presence of sulfates, MTBE decomposition can be attributed to oxidation not only by hydroxyl radicals, but also likely by SO4*- species. In the presence of chloride ions, it is possible that the dichloride radical is formed, which is less reactive than OH*. In the system under investigation, t-butyl alcohol was found to be the major byproduct, followed by t-butyl formate and acetone. The degradation rates of all intermediates and their inhibition in the presence of inorganic ions are similar to those obtained for MTBE, although their distributions are related to the concentrations of inorganic salts added.     

Treatment of oily port wastewater effluents using the ultraviolet/hydrogen peroxide photodecomposition system.

This paper presents the nonselective degradation of mechanically pretreated oily wastewater by hydrogen peroxide (H2O2) in the presence and absence of UV irradiation. The effect of chemical oxidation on wastewater biodegradability was also examined. The exclusive use of H2O2 photolyzed by daylight results in quite efficient degradation rates for the low peroxide concentrations used. Higher hydrogen peroxide concentrations inhibit degradation of organic contaminants in the wastewater. The degradation rates of all contaminants are relatively high with an advanced oxidation system (UV/H2O2), but degradation efficiencies are not distinguishably different when 20 or 45 minutes of UV irradiation is used. The excess of H2O2 used in the process can inhibit phenolic degradation and may lead to the formation of a new phenolic fraction. The biodegradability of port wastewater did not increase significantly following the application of the advanced oxidation process.     

Modeling of adsorption isotherms and kinetics of uranium sorption by magnetic ion imprinted polymers

Application of magnetic U(VI) ion imprinted polymers (IIPs) coated on magnetic nanoparticles was investigated for pre-concentration and determination of U(VI) ions in aqueous solutions. The scanning electron micrographs revealed the microporosity of the adsorbent. Uranium leaching was successful as the energy-dispersive X-ray spectra showed. The Brunauer–Emmett–Teller (BET) surface area improved by more than 13-fold (83.1 and 6.2 m² g^?1 for the leached and unleached magnetic IIP, respectively). U(VI) uptake was optimized using batch experiments with parameters affecting the uptake performance, such as initial uranium concentration, pH, contact time, and adsorbent dose investigated. Pseudo-second-order kinetics and the Langmuir isotherm model best fitted the experimental data. The maximum adsorption capacity of uranium onto the activated magnetic IIP reached 5.4 mg g^?1. The selectivity order was determined to be U(VI) > Ni(II) > Th(IV).     

Application of capillary electrophoresis combined with a modified BCR sequential extraction for estimating of distribution of selected trace metals in PM2.5 fractions of urban airborne particulate matter

The capillary electrophoresis (CE) method combined with a sequential extraction was applied to determine the distribution of Fe, Zn, Cu, Mn and Cd in urban ambient air PM2.5 samples. PM2.5 was collected on Teflon filters with dichotomous sampler, and the modified extraction procedure following the BCR leaching procedure was used to chemically fractionate metals into "easily exchangeable" with water, "acid extractable" with 0.11 mol/l acetic acid, "reducible" with 0.1 mol/l hydroxylamine hydrochloride acidified to pH 2.0 with nitric acid, and "oxidisable" with oxidation by 8.8 mol/l hydrogen peroxide (H2O2) followed by extraction with 1.0 mol/l ammonium acetate. Based on the obtained results it was concluded that the application of the studied methodology provides chemical fractionation data that reflect the general sources and potential health hazards of the studied metals.