Sergio Teggi

Adverse pregnancy outcomes in a population exposed to the emissions of a municipal waste incinerator

Some contaminants emitted by municipal waste incinerators are believed to adversely affect reproductive health in the exposed populations; yet only limited and conflicting epidemiologic evidence on this issue has been provided so far. In this study we analyzed rates of spontaneous abortion and prevalence at birth of congenital anomalies in women residing or working near the municipal solid waste incinerator of Modena, northern Italy, during the 2003--2006 period and who experienced higher levels of exposure to polychlorinated dibenzo-p-dioxins and dibenzofurans, compared to the remaining municipal population. In women residing in two areas close to the incinerator plant with increasing exposure to dioxins, we did not detect an excess risk of miscarriage (relative risk [RR] 1.00, 95% confidence interval [CI] 0.65-1.48) and of birth defects (RR 0.64, 95% CI 0.20-1.55), nor did any indication of dose-response relation emerge. Among female workers employed in the factories located in the exposed areas, we did not observe a higher risk of spontaneous abortion (RR 1.04, 95% CI 0.38-2.30); however, an increase in prevalence of birth defects was noted (RR 2.26), although this risk estimate was statistically very unstable (95% CI 0.57-6.14). Overall, the study results provide little evidence of an excess risk of adverse pregnancy outcomes in women exposed to emissions from a modern municipal solid waste incinerator.

Risk of congenital anomalies around a municipal solid waste incinerator: a GIS-based case-control study

BackgroundWaste incineration releases into the environment toxic substances having a teratogenic potential, but little epidemiologic evidence is available on this topic. We aimed at examining the relation between exposure to the emissions from a municipal solid waste incinerator and risk of birth defects in a northern Italy community, using Geographical Information System (GIS) data to estimate exposure and a population-based case-control study design. By modelling the incinerator emissions, we defined in the GIS three areas of increasing exposure according to predicted dioxins concentrations. We mapped the 228 births and induced abortions with diagnosis of congenital anomalies observed during the 1998–2006 period, together with a corresponding series of control births matched for year and hospital of birth/abortion as well as maternal age, using maternal address in the first three months of pregnancy to geocode cases and controls.ResultsAmong women residing in the areas with medium and high exposure, prevalence of anomalies in the offspring was substantially comparable to that observed in the control population, nor dose-response relations for any of the major categories of birth defects emerged. Furthermore, odds ratio for congenital anomalies did not decrease during a prolonged shut-down period of the plant.ConclusionOverall, these findings do not lend support to the hypothesis that the environmental contamination occurring around an incineration plant such as that examined in this study may induce major teratogenic effects.

Risk of hematological malignancies associated with magnetic fields exposure from power lines: a case-control study in two municipalities of northern Italy.

BackgroundSome epidemiologic studies have suggested an association between electromagnetic field exposure induced by high voltage power lines and childhood leukemia, but null results have also been yielded and the possibility of bias due to unmeasured confounders has been suggested.MethodsWe studied this relation in the Modena and Reggio Emilia municipalities of northern Italy, identifying the corridors along high voltage power lines with calculated magnetic field intensity in the 0.1-<0.2, 0.2-<0.4, and ≥ 0.4 microTesla ranges. We identified 64 cases of newly-diagnosed hematological malignancies in children aged <14 within these municipalities from 1986 to 2007, and we sampled four matched controls for each case, collecting information on historical residence and parental socioeconomic status of these subjects.ResultsRelative risk of leukemia associated with antecedent residence in the area with exposure ≥ 0.1 microTesla was 3.2 (6.7 adjusting for socioeconomic status), but this estimate was statistically very unstable, its 95% confidence interval being 0.4-23.4, and no indication of a dose-response relation emerged. Relative risk for acute lymphoblastic leukemia was 5.3 (95% confidence interval 0.7-43.5), while there was no increased risk for the other hematological malignancies.ConclusionsThough the number of exposed children in this study was too low to allow firm conclusions, results were more suggestive of an excess risk of leukemia among exposed children than of a null relation.

Evaluation of SO2 emission from Mount Etna using diurnal and nocturnal multispectral IR and visible imaging spectrometer thermal IR remote sensing images and radiative transfer models

We describe a model to evaluate the volcanic SO2 emission using images acquired by the airborne multispectral infrared and visible imaging spectrometer (MIVIS) in the thermal infrared spectral region. The estimating procedure consists of mapping of the SO2 columnar content and evaluation of the total SO2 flux emitted by the volcano. All the atmospheric radiative effects, including the SO2 plume emission/absorption, are computed by the MODTRAN 3.5 radiative transfer code. We apply the model to two MIVIS images acquired over Mount Etna, located on the east coast of Sicily, Italy, during the “Sicilia-94” remote sensing campaign on July 24 and 25, 1994. The June 25 image was acquired during the night; this is the first attempt to estimate the SO2 content in volcanic plume using nocturnal thermal infrared images. The total flux estimates range from 20.9 kg s−1 (1810 t d−1) to 82.2 kg s−1 (7100 t d−1) depending on the plume geometry used in the procedure. These results, except one case (82.2 kg s−1), are in agreement with the estimates derived from correlation spectrometer (COSPEC) measurements collected during the same period. We also evaluate the dependencies of the results on several parameters such as plume geometry, surface emissivity, water vapor content, and wind speed.

Passive exposure to agricultural pesticides and risk of childhood leukemia in an Italian community

BACKGROUND Exposure to pesticides has been suggested as a risk factor for childhood leukemia, but definitive evidence on this relation and the specific pesticides involved is still not clear. OBJECTIVE We carried out a population-based case-control study in a Northern Italy community to assess the possible relation between passive exposure to agricultural pesticides and risk of acute childhood leukemia. METHODS We assessed passive pesticide exposure of 111 childhood leukemia cases and 444 matched controls by determining density and type of agricultural land use within a 100-m radius buffer around childrens homes. We focused on four common crop types, arable, orchard, vineyard and vegetable, characterized by the use of specific pesticides that are potentially involved in childhood induced leukemia. The use of these pesticides was validated within the present study. We computed the odds ratios (OR) of the disease and their 95% confidence intervals (CI) according to type and density of crops around the childrens homes, also taking into account traffic pollution and high-voltage power line magnetic field exposure. RESULTS Childhood leukemia risk did not increase in relation with any of the crop types with the exception of arable crops, characterized by the use of 2.4-D, MCPA, glyphosate, dicamba, triazine and cypermethrin. The very few children (n=11) residing close to arable crops had an OR for childhood leukemia of 2.04 (95% CI 0.50-8.35), and such excess risk was further enhanced among children aged <5 years. CONCLUSIONS Despite the null association with most crop types and the statistical imprecision of the estimates, the increased leukemia risk among children residing close to arable crops indicates the need to further investigate the involvement in disease etiology of passive exposure to herbicides and pyrethroids, though such exposure is unlikely to play a role in the vast majority of cases.

Tri-generation power plant and conventional boilers: pollutant flow rate and atmospheric impact of stack emissions

The atmospheric impact of stack emissions from a power plant (tri-generator and boilers) that will be installed in an urban area in the central Po valley (Northern Italy), characterized by calm wind events, is studied and compared with the impact of the existing plant (conventional boilers). Both the plants are supplied by methane gas. The atmospheric dispersion of NOx emitted is simulated, both in the current and future scenario, by the software package ARIA INDUSTRY. The NOx emission rates are set equal to the regulatory emission limits for existing and future boilers, while the tri-generation system emission rates are set equal to the emission limits certified by the system manufacturer. The simulation periods focus over the 2010 winter season. The simulation estimates the impact of NOx emissions on air quality (vertical concentration profiles and concentration maps at the ground) in the urban area close to the plant. The future power plant impact on air quality results lower than the impact of the existing plant, even if the yearly total mass of pollutants emitted in atmosphere from the new power plant is higher than from the existing plant. The emissions of conventional boilers result the main responsible of the air pollution at the ground in the future scenario.

A technique for spatial sharpening of thermal imagery of coastal waters and of watercourses

Although satellite thermal infrared (TIR) remote sensing is a valuable tool for the thermal mapping of coastal waters and watercourses, it has many problematic issues, the most important of which are linked to spatial resolution. In the literature, several algorithms for sharpening thermal imagery can be found. Nevertheless, most of them are devoted to land temperature and are not applicable to water–land mixed pixels. In this article, a new algorithm for sharpening water thermal imagery (SWTI) at the water–land boundaries is presented. SWTI is based on the assumption that a relationship exists between the TIR radiance emitted by the pixels of the scene and the fractional water coverage, the fractional non-vegetated soil coverage and a variable describing the presence of vegetated soils. The algorithm works on a pixel by pixel basis and the results are accepted or refused using an analysis of variance (ANOVA) test. SWTI was applied to two Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) scenes acquired on areas where complex water surfaces are present: the delta of the Po river and the lagoon of Venice (Italy). The spatial resolution of ASTER TIR scenes was improved from 90 to 30 m. Different variables were tested to represent vegetated soils, and the SWTI sensitivity to them has been inspected. The performance of SWTI has been studied using visual inspection and statistical and simulation methods. Visual inspection indicated that the spatial enhancement was significant for most of the water surfaces and, in particular, for watercourses. Most of the details with dimension ≥60 m (i.e. 2 pixels at the final spatial resolution) were discernible. Quantitative analysis showed that the algorithm was successfully applicable for 94% and for 84% of the mixed pixels at the water–land boundary in the Po and in the Venice case studies, respectively. Expected and maximum errors were 1 and 1.4 K in the Po case, and 1 and 2.1 K in the Venice case. These values can be considered satisfactory when compared with the ASTER thermal accuracy (1 K). Further research is required to confirm the accuracy and performance analysis using methods based on accurate and higher resolution thermal imagery and on ground measurements.

Inspecting MIVIS capability to retrieve chemical-mineralogical information: evaluation and analysis of VNIR-SWIR data acquired on a volcanic area

This work is a contribution to the assessment of MIVIS (Multi-spectral Infrared and Visible Imaging Spectrometer) airborne imaging spectrometer capability in applications of surface characterization. The focus is on the visible and near-infrared–short wave infrared (VNIR–SWIR) spectral region, using a dataset acquired in 1994 on Vulcano Island (Italy), to retrieve chemical–mineralogical information on the altered deposits related to volcanic activity. The main processing steps include data quality evaluation in terms of signal-to-noise ratio, atmospheric and topographic corrections and spectral interpretation of the image. Estimation of surface reflectance is based on atmospheric modelling by MODTRAN3.5 and 6S radiative transfer codes. Representative MIVIS reflectance spectra of the main surface units are compared with spectra measured in the laboratory on field samples, and interpreted to characterize the mineralogy on the basis of their spectral features. A thematic map of the main alteration units is then produced by applying spectral mapping techniques to the surface reflectance image, using a set of channels selected on the basis of their data quality and image-derived end-member spectra.

Analysis of temperature maps of waterbodies obtained from ASTER TIR images

Thermal water pollution is a highly relevant issue to which increasing attention is being paid. Satellite remote sensing represents a useful tool for the mointoring and study of the temperatures of waterbodies. The purpose of this work is to define a methodology for the analysis of the surface temperature maps of coastal waterbodies and watercourses from satellite images for quality assessment and for regulatory purposes. Three different procedures are developed in order to study the temperature field of waterbodies, to extract the temperature profile at a fixed distance from the coastline and to analyse the cross sections of the watercourses as prescribed by the law. Extraction and analysis of surface temperature patterns are undertaken using image segmentation techniques. This work also represents a first test of the advantages given by the Sharpening Water Thermal Imagery (SWTI) algorithm, which improves the spatial resolution of Advanced Space-borne Thermal Emission and Reflection Radiometer (ASTER) images from 90 to 30 m. The developed procedures and the SWTI algorithm are applied to ASTER images acquired on the lagoon of Venice and on the delta of the Po River. Statistical parameters and temperature profile are extracted in order to verify compliance with legal limits. The use of the developed procedures enables the individuation and quantification of thermal anomalies such as industrial discharges both in the sea and in watercourses.

Surface temperature and emissivity from NOAA images

SummaryA procedure to determine the surface temperature from images taken by AVHRR (advanced very high resolution radiometer) on board NOAA11 satellite is described in this paper. The importance of the emissivity parameter to estimate the surface temperature and the possibility to compute both temperature and emissivity maps from the two thermal infrared channels of the AVHRR is shown.