Levels and congener profiles of polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and dioxin-like polychlorinated biphenyls in cow’s milk collected in Campania, Italy

Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and certain dioxin-like polychlorinated biphenyls (dl-PCBs) are a family of chemically-related lipophilic compounds characterized by similar toxicity. Due to their properties they are universally distributed in the environment and classified as persistent organic pollutants (POPs). From most of studies carried out to evaluate human dietary intake, milk and dairy products result as a major contributors of PCDD/Fs uptake. Of course the main source of milk contamination is animal feeds. Lactating ruminants, cows included, transfer these compounds to the food chain by ingestion of contaminated vegetables or soil. Their resistance to degradation and a high lipophilicity means that PCDD/Fs and dl-PCBs may be accumulated into fat tissues from which they are transferred to milk during lactation period.Seventy-nine cows milk samples, collected in the monitoring plan 2008, were analyzed for PCDD/Fs and dl-PCBs. Eleven milk samples were non-compliant corresponding to five breeding livestock located in Caserta province. The distribution of PCDD/Fs and dl-PCBs congeners in these samples was examined in order to determine the likely sources of dioxins. The results show that the congener profile is characterized by a prevalence of PCDFs in respect of PCDDs, that represents the typical pattern of thermal origin contamination.     

Atmospheric deposition of PCDD/Fs near an old municipal solid waste incinerator: levels in soil and vegetation

The levels of polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) were determined in soil and vegetation samples taken from 24 sites in the vicinity of an old municipal solid waste incinerator (San Adrià del Besòs, Barcelona, Spain). Duplicate samples were collected within a radius of 3 km from the stack. PCDD/F concentrations in soils ranged from 1.22 to 34.28 ng I-TEQ/kg (d.m.) with median and mean values of 9.06 and 12.24 ng I-TEQ/kg, respectively. In turn, the levels of PCDD/Fs in vegetation samples ranged from 0.33 to 1.98 ng I-TEQ/kg (d.m.), with median and mean values of 0.58 and 0.70 ng I-TEQ/kg, respectively. Although the present PCDD/F concentrations in soil samples were higher than those recently found in soils taken near other incinerators from Catalonia, they are of the same order of magnitude than the levels of these pollutants found in incinerators from other countries. By contrast, the concentrations of PCDD/Fs in herbage samples were comparable to those found in recent surveys carried out in Catalonia.     

Congener profiles of PCDD/Fs in soil and vegetation samples collected near to a municipal waste incinerator

Recently, we measured the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) in soil and herbage samples collected in the vicinity of a municipal solid waste incinerator (MSWI) from Tarragona (Catalonia, Spain). Since these concentrations could be increased by the presence of other emission sources of PCDD/Fs in the same area in which the MSWI is placed, the main goal of the present study was to determine the PCDD/F congener profiles in the soil and vegetation samples collected in 1996 and again in 1997 near to the facility and to compare with those from samples collected in a close area outside of direct emissions of the plant. From an accurate inspection of the PCDD/F congener profiles, it was concluded that PCDD/F emissions from the MSWI here examined are neither the only nor the main responsible for the presence of PCDD/Fs in the samples of environmental matrices collected in the area under direct influence of the plant.     

Characteristics of PAHs, PCDD/Fs and PCBs in sediment following forest fires in northern Alberta

Extensive forest fires occurred in northern Alberta, Canada, in 1998. Polynuclear aromatic hydrocarbons (PAHs), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and polychlorinated biphenyls (PCBs) were studied following these forest fires in order to explore natural and anthropogenic influences on the affected forest fire area. Specifically, concentrations and profiles of these compounds were determined in sediment samples. A predominance of alkylated PAH derivatives over parent PAHs were observed at the burned and reference sites. Naturally dervied PAHs were abundant at all sites. A high proportion and concentration of retene was observed at the totally burned site and indicates some inputs from forest fires. Very low concentrations of PCDD/Fs and PCBs were observed at all sites, and the profiles were very similar. This likely reflects common atmospheric contributing sources to the study area.     

Atmospheric deposition of polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, and dioxin-like polychlorinated biphenyls in the Kanto Region, Japan

The atmospheric bulk (dry and wet) deposition of dioxins was investigated at four locations (Tokyo, Yokohama, Tsukuba, and Tanzawa) in the Kanto region (in Japan) over one year using a stainless-steel pot. Annual average polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans (PCDD/PCDF) deposition fluxes were estimated to be from 450 to 1300 ng/m2/yr, and the annual average TEQ fluxes from 5.7 to 17 ng-TEQ/m2/yr at the four locations. The PCDD/PCDF deposition flux was higher in winter than in summer. The deposition flux could be related to ambient temperature, particularly for less chlorinated PCDDs/PCDFs, while the deposition flux is not necessarily related to the amount of precipitation. The PCDD/PCDF deposition flux increased as the particle deposition flux increased, for the winter samples. Based on the ratio of the PCDD/PCDF deposition fluxes to the particle deposition fluxes, the contribution of the reentrainment of soil particles to the TEQ of PCDD/PCDF deposition was considered to be negligible in this region. Based on the air concentrations monitored near our deposition sampling points by the municipalities, the ratio of the annual deposition flux to the annual average air concentration was roughly estimated to be 0.082 cm/s. The range of deposition flux in the Kanto region was estimated to be from 1.5 to 31 (median: 9.8) ng-TEQ/m2/yr based on the range of air concentration data measured by the municipalities. The total annual deposition flux in the entire Kanto region was estimated to range from 50 to 900 g-TEQ/yr (median 320 g-TEQ/yr). This estimated flux was of the same order as the sum of estimated emissions from municipal solid waste incinerators and industrial waste incinerators in the Kanto region. The contributions of dioxin-like PCBs in Yokohama, Tsukuba, and Tanzawa depositions were less than 10% of the total TEQ; however, in Tokyo it was almost equal to or more than 50%.     

Analysis of polychlorinated dibenzo-p-dioxins and furans in various aqueous samples in Taiwan

Twenty-one fresh water samples were taken from reservoirs, wells and drinking water treatment plants in Taiwan for measurement of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F) concentrations. Due to low concentration of PCDD/Fs, water samples (400-1000 L) were collected by using the on-site large volume pre-concentration system and analyzed by high resolution gas chromatography (HRGC)/high resolution mass spectrometer (HRMS). Different characteristics of dioxin profiles in surface water and groundwater are observed. The PCDD/F concentrations in fresh water samples varied from 0.001 to 0.265 pg WHO₉₈-TEQ/L which are lower than the standard (12 pg WHO₉₈-TEQ/L) set by the Taiwan Environmental Protection Administration (TEPA) for drinking water. Only a small fraction (<5%) of the total PCDD/F concentration in fresh water samples was water-soluble. As a result of their hydrophobicity, PCDD/Fs are effectively removed along with suspended solid via the water treatment process (average 98% removal efficiency).     

Temporal and local trends of PCDD/F levels in cow's milk in Switzerland

Levels of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F) were determined in 30 Swiss cow's milk samples collected at dairy farms in the vicinity to point sources, in rural/alpine areas distant to known sources, and from tanks in large industrial milk processing plants. The contaminant concentrations in samples collected in 2001 were compared to data from analyses conducted in 1984 and 1990/1991 at the same sites. In 2001, the PCDD/F levels in milk from farms near point sources (0.63+/-0.26 ng I-TEQ/kg milk fat) are slightly but significantly higher in than milk from remote areas (0.36+/-0.09 ng I-TEQ/kg milk fat). Consumer milk collected at the processing plants had intermediary levels (0.51+/-0.19 ng I-TEQ/kg milk fat). However, milk in 2001 was significantly less contaminated than the samples collected in 1990/1991 and 1984. This trend is particularly pronounced near point sources but is also apparent in consumer milk and milk from remote areas. No geographical gradient in the atmospheric input of PCDD/F in Switzerland was found. The reduction in PCDD/F levels in dairy milk is paralleled by and correlated to the remediation of known PCDD/F emitting industries, as enforced by federal authorities.     

Correlation coefficients between the dioxin levels in mother's milk and the distances to the nearest waste incinerator which was the largest source of dioxins from each mother's place of residence in Tokyo, Japan

BACKGROUND: To observe the relationship between the PCDD/F and Co-PCB levels in samples of human breast milk and nearby waste incinerators in Tokyo, Japan. METHODS: Breast milk was taken from 240 mothers residing in Tokyo, Japan to measure and analyze the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs; 14 congeners), polychlorinated dibenzofurans (PCDFs; 15 congeners), and coplanar polychlorinated biphenyls (Co-PCBs; 12 congeners) contained in the fat. Individual milk samples (about 50 ml) were obtained from the mothers 30 days after delivery, between the months of June and September in 1999 and 2000. A map of Tokyo was used to measure the distances between each mother's place of residence and the closest public and industrial waste incinerators. RESULTS: The distances to the nearest waste incinerators bore no apparent correlations with the congeners of PCDD/Fs and Co-PCBs. The distances were also uncorrelated with the mean toxic equivalent quantities (TEQs) of PCDD/Fs (the sum of PCDDs and PCDFs), Co-PCBs, and the total PCDD/Fs and Co-PCBs. CONCLUSIONS: Although waste incinerators were the largest source of dioxins in Japan at the time of the study, the dioxins levels of mother's milk bore no apparent relationships with the distances between the mothers' domiciles and the nearest waste incinerators. In this study, several meaningful factors were not taken into account, namely, the wind direction, the level of dioxin emitted from each incinerator, the level of environmental pollution of dioxins, and the average time the mothers stayed at home each day. A full understanding of these points awaits future studies.     

Source identification of PCDD/Fs in agricultural soils near to a Chinese MSWI plant through isomer-specific data analysis

Isomer-specific data were investigated in order to identify the sources of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in agricultural soils, including Fluvo-aquic and paddy soils, in the vicinity of a Chinese municipal solid waste incineration (MSWI) plant. Homologue and isomer profiles of PCDD/Fs in soils were compared with those of potential sources, including combustion sources, i.e., MSWI flue gas and fly ash; and the impurities in agrochemicals, such as the pentachlorophenol (PCP), sodium pentachlorophenate (PCP-Na) and 1,3,5-trichloro-2-(4-nitrophenoxy) benzene (CNP). The results showed that the PCDD/F isomer profiles of combustion sources and agricultural soils were very similar, especially for PCDFs, although their homologue profiles varied, indicating that all the isomers within each homologue behave identically in the air and soil. Moreover, factor analysis of the isomer compositions among 33 soil samples revealed that the contamination of PCDD/Fs in agricultural soils near the MSWI plant were primarily influenced by the combustion sources, followed by the PCP/PCP-Na and CNP sources. This implication is consistent with our previous findings based on chemometric analysis of homologue profiles of soil and flue gas samples, and identifies PCP/PCP-Na as an additional important source of PCDD/Fs in the local area. This makes the similarities and differences of isomer profiles between Fluvo-aquic and paddy soils more explainable. It is, therefore, advisable to use isomer-specific data for PCDD/F source identifications where possible.     

Polychlorinated dibenzo-p-dioxins/furans and polychlorinated biphenyls in sediments and aquatic organisms from the Taihu Lake, China

Sediments at 16 sites and muscles of four aquatic species collected in Taihu Lake were analyzed for polychlorinated dibenzo-p-dioxins, dibenzofurans (PCDD/Fs) and polychlorinated biphenyls (PCBs) by HRGC/HRMS. The concentrations of total PCDD/Fs, PCBs and WHO-TEQ were 120.1-1315.1pg/gdw, 889.7-29747.8pg/gdw, and 0.83-17.72pgTEQ/gdw, respectively in sediments; and those in muscles were 5.49-35.84pg/gww, 1517.10-27647.98pg/gww, and 0.52-3.83pgTEQ/gww respectively. The concentrations of PCDD/Fs and PCBs in the sediments were decreasing gradually along the water flow. The pollution levels were compared with other studies and the possible sources were discussed.     

Methods for treating soils contaminated with polychlorinated dibenzo-p-dioxins, dibenzofurans, and other polychlorinated aromatic compounds

This review provides a summary of methods for treating soils contaminated with polychlorinated aromatic compounds, especially polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). Unlike many other soil pollutants, PCDD/Fs bind tightly to the soil, which severely reduces the efficiency of most aqueous treatment procedures and leaves few realistic alternatives besides the traditional containment techniques (landfill, solidification/stabilization, and in situ vitrification). Incineration has long been, and still is, the most efficient destruction technique, with a removal efficiency of >99.9999%. However, supercritical water oxidation, base-catalyzed decomposition, steam distillation, and various extraction techniques, such as solvent and liquefied gas and subcritical water extraction, may provide removal efficiencies of >95%. Many of the alternative techniques are expected to be cheaper than incineration and may therefore be attractive for moderately polluted soils. However, some of them are at an early stage of development and need to be further tested before their true potential can be assessed.     

Analysis of dioxin-like compounds in vegetation and soil samples burned in Catalan forest fires. Comparison with the corresponding unburned material

Only a few data are reported about the formation of polychlorinated dibenzo-p-dioxins (PCDD) and dibenzofurans (PCDF) in forest fires. However, the inventories of sources undertaken by several European and American countries consider natural fires as a possible source of PCDD/F and, in some cases, as one of the most important. In our work we have analysed vegetation and soil samples burned in four forest fires which happened in Catalonia in the summer of 1998. The concentration of dioxin-like compounds (PCDD/F, non-ortho polychlorinated bi-phenyls (PCB) and mono-ortho PCB) has been compared to the concentration present in the corresponding unburned material collected in places near the fires but not affected. The results of this preliminary study show very low concentrations in all the samples, both burned and unburned. Although a change in the profile (proportional increase of tetrachlorinated congeners in PCDD/F) is observed in burned samples compared to unburned ones, the absolute values of concentration decrease in most samples. Therefore, natural fires seem not to be an important source of dioxin-like compounds. These results will be confirmed with air emissions measurements in future studies.     

Release of polychlorinated dibenzo-p-dioxins and dibenzofurans by setting off fireworks.

Selected pyrotechnic articles were set off under laboratory conditions. Residues and vapors of smoke as well as unburnt charges were analyzed for polychlorinated dibenzo-p-dioxins, dibenzofurans (PCDD/F) and their precursors chlorinated benzenes and phenols. The contamination of the selected products with these organic xenobiotics proved to be very variable. Remains of fireworks contained octachlorinated dioxins and furans up to 142 ng I-TEQ/kg as well as hexachlorobenzene in the range of 0.05 to 1,400 mg/kg. The deflagration of detonating compositions usually resulted in a dispersion of contaminants, whereas continuously burning flare compositions partially led to a thermal decomposition of organic pollutants. A significant rate of formation of polychlorinated dioxins and furans was observed when setting off blue-lightning rockets and fountains. Further investigations revealed that even high temperatures during the deflagration of black powder charges could not suppress the formation of PCDD/F from appropriate precursors.     

PCDD/Fs and PCBs in airborne particulate matter of the greater Thessaloniki area, N. Greece

Particle-bound polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and polychlorinated biphenyls (PCBs) were monitored at two sites in northern Greece for an eight-month period in 1999. PCDD/F concentrations were close to the lower end of reported values worldwide. Excepting a few cases, the PCDD/Fs homologue profile was stable. The gaseous PCDD/F fractions calculated were found to account for a small percentage of the total concentrations (<2% for OCDD/Fs and HpCDD/Fs, while 30-35% for TCDFs). Particle-bound PCBs were also found at low concentrations which, however, were higher at the urban site. Calculations of the dry deposition of particulate PCDD/ Fs and PCBs gave mean values of 0.52 and 0.59 pg I-TEQ/m2/day of PCDD/Fs, while 242 and 74 pg/m2/day of sigmaPCBs for the urban and the semirural areas respectively. An anticorrelation of PCDD/F concentrations with ambient temperature was derived particularly for the lower chlorinated congeners. A weak association with winds of western and southern origin was also observed. Factor analysis and literature source profiles were employed to identify possible emission sources. It was appeared that the PCDD/F compositional pattern of TSP is influenced by mixed sources the most prominent being uncontrolled fires and car exhausts.     

Concentrations of PCDD/PCDF in soil close to a secondary aluminum smelter

Polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDDs/Fs) were analyzed in samples of the emissions from a secondary aluminum smelter (ALS) and soil samples around the plant. The purpose was to estimate the impact of the emissions on the surrounding environment.PCDD/F soil concentrations were higher in the proximity of the plant, exceeding the limit adopted in Italy in soils for green areas and residential uses and the upper limit of several reference concentrations. The most contaminated sites were less than 500 m from the plant and the dioxin concentration with the distance from the ALS.Principal component analysis (PCA) showed that emissions from the ALS were the source of PCDD/F contamination in the soils closest to the plant. Multivariate data analyses such as PCA are therefore useful to identify sources of emission causing contamination.     

PCDD/F concentrations in soil and vegetation in the vicinity of a municipal waste incinerator after a pronounced decrease in the emissions of PCDD/Fs from the facility

Emission of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) by municipal solid waste incinerators (MSWI) is an issue of great concern. In 1997, an adaptation to the EU legislation on pollutant emissions from the stack was carried out in an MSWI from Tarragona (Catalonia, Spain). As a result, PCDD/F emissions were significantly reduced. The aim of this study was to determine the current levels of PCDD/Fs in soil and vegetation samples collected near the facility and to compare these levels with those obtained in previous surveys (1996 and 1997). In the period 1997-1999, PCDD/F concentrations in vegetation samples were significantly decreased (60%). By contrast, the levels of PCDD/Fs in soil samples increased slightly (14%, P > 0.05) during the same period. An exhaustive analysis of the present data indicates that other emission sources of PCDD/Fs have also a notable environmental impact on the area under direct influence of the MSWI.     

Dioxins (polychlorinated dibenzo-p-dioxins and polychlorinated dibenzo-furans) in traditional clay products used during pregnancy

Geophagy, the practice of consuming clay or soil, is encountered among pregnant women in Africa, Eastern Asia and Latin America, but also in Western societies. However, certain types of clay are known to contain high concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). The aim of this study was to determine the PCDD/F contents of orally consumed clays purchased from Dutch and African markets. Congener patterns were compared with those of pooled human milk samples collected in eight African countries, to investigate a possible relationship with clay consumption. From the Dutch market thirteen clay products were examined, seven of African and six of Suriname origin. From seven African countries, twenty clay products were collected. All 33 clay products were screened with a cell-based bioassay and those showing a high response were analyzed by GC/HRMS. High PCDD/F concentrations were measured in three clay products from the Dutch market, ranging from 66 to 103 pg TEQ g^-1, whereas clay products from African countries were from 24 to 75 pg TEQ g^-1. Patterns and relatively high concentrations of PCDD/Fs in human milk samples from the Democratic Republic of the Congo and Côte d’Ivoire suggest a relationship with the consumption of contaminated clay. Frequent use of PCDD/F contaminated clay products during pregnancy may result in increased exposure of the mother and subsequently the developing fetus and new-born child. The use of these contaminated clays during pregnancy should be carefully considered or even discouraged.     

Distribution of PCDDs and PCDFs in Soils Collected from the Denver Front Range - Principal Components Analysis of Diffuse Dioxin Sources (10 pp)

Background, Aims and Scope The Rocky Mountain Arsenal (RMA) is a US Army facility located northeast of Denver, Colorado that has been listed on the National Priorities List (NPL). It is currently being re-mediated under the authority of the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) and the Superfund Amendments and Reauthorization Act of 1986 (SARA). As part of the remediation activities at RMA, indications were found that a source of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) had existed on the RMA. As a result, investigations were undertaken to assess the possible nature and extent of any potential sources of PCDDs and PCDFs on the RMA site. In addition, other studies were conducted that examined PCDD/PCDF contamination in the Denver area. The goal of these studies was to examine nature and extent of PCDD/PCDF contamination both on the RMA as well as in the surrounding Denver area. The intent of this study was to characterize sources of dioxins (PCDDs) and dibenzofurans (PCDFs) at low environmental concentrations which might have originated from diffuse sources in the Denver Colorado area and in particular, the Rocky Mountain Arsenal (RMA) using Principal Component Analysis (PCA). Methods Over 200 soil samples were collected from the RMA and the Denver area. From the RMA, soil was collected as part of three studies that included a (1) random site-wide sampling of the RMA, (2) soils from the Western Tier Parcel (WTP), and (3) soils from Historic Use areas. Denver area soil samples were collected from five different land use categories: Residential, Agricultural, Open Space, Commercial, and Industrial. PCA was conducted on concentrations of 17 2,3,7,8-substuituted PCDD and PCDF congeners in 220 soil samples collected from the RMA and the Denver Front Range region. Results and Discussion PCA demonstrated the presence of possible minor sources of dioxins on the RMA. Current remediation efforts on RMA will result in the removal of these sources. Samples from the RMA were identified by the presence of a congener profile containing higher chlorinated PCDFs while the Denver Front Range areas were characterized by the presence of higher chlorinated PCDD congeners. The presence of a PCDF signature for the RMA samples does not necessarily indicate a major source of these contaminants on-site. Indeed, the relatively diffuse nature of the sample clusters would argue strongly against the presence of a single large source. Instead, the predominance of the PCDF congeners probably indicates the mixed industrial activities that took place on and near the site. Conclusion PCA results indicate that PCDD/PCDF profiles in soils collected from the RMA differed from those collected from the outlying Denver areas but that a major source of these contaminants was not present. Rather, the diffuse nature of sample clusters from the PCA indicated that the congener profile of RMA samples was most likely a result of the mixed industrial activities that historically have taken place on and near the site. PCA also indicated that many of the 'open area' (peripheral site-wide) RMA soils samples did not differ from Denver are reference congener profiles. This finding was also true for samples collected from the WTP that were essentially indistinguishable from Off-RMA reference samples. In addition, total TEQ concentrations in soils collected from WTP were similar to those measured in soils collected from the Denver Front Range areas indicating that lack of a major source of PCDD/PCDF within the WTP zones of the RMA. Recommendation and Outlook Analytical as well as statistical results of the soil congener data indicate that the WTP soils are indistinguishable from soils collected from non-industrial areas in the Denver area. This finding would support the recent 'de-listing' of the WTP from the other RMA areas and its' transfer to other authorities in the Denver area.     

Concentrations of polychlorinated dibenzo-p-dioxins in processed ball clay from the United States

Processed ball clays commonly used by the ceramic art industry in the United States were collected from retail suppliers and analyzed for the presence and concentration of the 2,3,7,8-Cl substituted polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/PCDFs). The average PCDD toxic equivalent (TEQ) concentrations of these processed ball clays was approximately 800 pg/g (TEQ-WHO) with characteristic congener profiles and isomer distributions similar to patterns of previously analyzed raw and processed ball clays. The PCDF concentrations were below the average limit of detection (LOD) of 0.5 pg/g. Correlation analyses reveal no significant relationship between total organic carbon (TOC) and either individual, homologues, and total tetra-through octa-chlorinated PCDD congeners, or TEQ concentrations of the processed ball clays. The results are consistent with earlier studies on levels of PCDDs in ball clays. Data from earlier studies indicated that dioxins may be released to the environment during the processing of raw clay or the firing process used in commercial ceramic facilities. The presence of dioxin in the clays also raises concerns about potential occupational exposure for individuals involved in the mining/processing of ball clay, ceramics manufacturing and ceramic artwork.     

Concentrations of PCDD/PCDF in soil close to a secondary aluminum smelter

Polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDDs/Fs) were analyzed in samples of the emissions from a secondary aluminum smelter (ALS) and soil samples around the plant. The purpose was to estimate the impact of the emissions on the surrounding environment.PCDD/F soil concentrations were higher in the proximity of the plant, exceeding the limit adopted in Italy in soils for green areas and residential uses and the upper limit of several reference concentrations. The most contaminated sites were less than 500 m from the plant and the dioxin concentration with the distance from the ALS.Principal component analysis (PCA) showed that emissions from the ALS were the source of PCDD/F contamination in the soils closest to the plant. Multivariate data analyses such as PCA are therefore useful to identify sources of emission causing contamination.