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.     

Retention time profiling of all 136 tetra- through octa- chlorinated dibenzo-p-dioxins and dibenzofurans on a variety of Si-Arylene gas chromatographic stationary phases

The applicability of three different Silphenylene Silicone co-polymer (Si-Arylene) GC stationary phases (J&W Scientific DB-5ms, Varian VF-5ms, and VF-Xms) has been evaluated for the separation of all 136 tetra- through the octa- chlorinated dibenzo-p-dioxins (PCDD) and chlorinated dibenzofurans (PCDF) from closely eluting isomers using gas chromatography/high resolution mass spectrometry (GC/HRMS). Their relative performance data are compared to the “conventional” 5% diphenyl 95% dimethylpolysiloxane GC column (Supelco Equity-5) and to each other based on absolute retention times, visualized mass chromatograms, and the separation of 2,3,7,8-substituted isomers. VF-Xms GC column was able to demonstrate a better performance towards separation of 2,3,7,8-substituted PCDD/PCDF compared to other Si-Arylene GC columns tested, where only 2,3,4,7,8-PnCDF can not be resolved from 1,2,3,6,9-PnCDF and 2,3,4,6,7,8-/1,2,3,6,8,9-HxCDF and 1,2,3,7,8,9-/1,2,3,4,8,9-HxCDF can be at least partially resolved. These data suggest that the development of a single GC column for the separation of all 17 2,3,7,8-substituted dioxins and furans is feasible, which therefore could be used as a standard tool for the PCDD/PCDF methods globally including USEPA methods 1613b, 8290A, 8280B, European Standard Method EN 1948, Canadian methods DFPCB-E3418, EPS 1/RM/19, Japanese methods JIS K0311 and JIS K0312. Having one specific GC column to separate all 2,3,7,8-substituted PCDD/PCDF will significantly improve the data quality, comparability by the various methods and assessment techniques while simultaneously leading to a more cost and time efficient operation.     

Sources and distribution of polychlorinated-dibenzo-p-dioxins and -dibenzofurans in soil and sediment from the Yellow Sea region of China and Korea

Polychlorinated-dibenzo-p-dioxins and -dibenzofurans (PCDD/Fs) were measured in soils and sediments from the Yellow Sea region. Korean soils and sediments mostly contained detectable PCDD/Fs and showed a widespread distribution among locations. Soil and sedimentary PCDD/Fs from China were comparable to or less than those in Korea. The patterns of relative concentrations of individual congeners in soils were different between the two countries, but similar in sediments. Sources of PCDD/Fs in China and Korea were found to be independent of each other and their distributions reflected matrix-dependent accumulation. Spatial distribution indicated some point sources in Korea while Chinese sources were more widespread and diffuse. PCDD/Fs measured in the coastal areas of the Yellow Sea were comparable to or less than those previously reported in for eastern Asia. However, ∑TEQs in soils and sediments were near to or, in some cases exceeded environmental quality guidelines.     

PCDD/F-contamination in a hexachlorocyclohexane waste site in Rio de Janeiro,Brazil

In the 1950s, a production plant of hexachlorocyclohexane (HCH) was established in Brazil with the main purpose of producing chemicals for vectors control. This factory was closed down in 1955 and around 300 tons of production residues were left behind in the open air. In 1995, the area was treated with lime to eliminate the HCH contamination. Soil sample gave a PCDD/F concentration of 13 900 ng I-TEQ/kg whereas samples from the neighborhood ranged from 0.19 to 2.08 ng I-TEQ/kg. PCDD/F levels in cow's milk samples varied from 4.1 to 6.5 pg I-TEQ/g of milk fat. High concentration in soil collected from the site suggests that treatment and recovery shall be made. Further dioxin monitoring is needed to better estimate the risk posed to local population through food consumption and soil usage.     

Polychlorinated -dibenzo-p-dioxins/furans and -dioxin-like biphenyls in eggs of common terns from lime island,St. Mary's river,Michigan, USA

Population collapse of common tern (Sterna hirundo) from Lime Island in the St. Mary's River, Michigan, USA were related to the 2,3,7,8-chlorine substituted dioxins, furans, dioxin-like PCBs, and other possible factors using unhatch egg target contaminant analysis. The most toxic congeners, 2,3,7,8-TCDD/DF was found in all samples at noticeable concentrations. Magnitude of sum 2,3,7,8-PCDD/DFs were within the range of 39–93?pg/g wet wt. Dioxin-like PCBs were within the range of 360–1230?ng/g wet wt. Great Toxic Equivalent Quantity (TEQ) contributions by 2,3,7,8-TCDF, 2,3,4,7,8-PeCDF, 2,3,7,8-TCDD, 1,2,3,7,8-PeCDD, and dioxin-like PCBs such as CB-77, CB-126 and CB-105 are considered greatly due to their influence of poor embryo development and consequent damage of embryos of common terns in egg injection studies. However, other organochlorines, heavy metals, and/or synergistic effects also taken in to account. On the whole, TEQs in the tern eggs were greater than the Lowest-Observable-Adverse Effect Level (LOAEL) for bald eagle (Haliaeetus leucocephalus) embryos observed in British Columbia, Canada. Concentrations of dioxin-like PCBs, dioxins, furans in the St. Mary's River food chain are at levels for concern for nesting colonial waterbirds. Eventually, the possible movements of analyzed chemicals downstream from a man-made flood event are discussed.     

Portuguese inventory of dioxins and furans atmospheric emissions

This article presents the results of the most recent estimation of polychlorinated dibenzo-p-dioxins (PCDD) and dibenzofurans (PCDF) atmospheric emissions in Portugal, which has covered the period 2004–2009 and includes 27 emission sources types. The results are compared with previous emissions inventories published for Portugal. The main objective of this work is to provide relevant information about the amounts of the compounds that are released into the atmosphere in Portugal, and identify their major sources and trends.     

Toxic Environmental Releases from Medical Waste Incineration: A Review

Toxic releases from medical waste incineration comprising organic emissions such as polychlorinated dibenzo-dioxin/furan (PCDD/Fs) and polycyclic aromatic hydrocarbons (PAHs), inorganic emissions and ashes containing toxic metals have been reviewed. Attempts made by various investigators to reduce/eliminate emissions have also been included. Legislations concerning emission standards for medical waste incinerators have been discussed.     

The conversion of chicken manure to biooil by fast pyrolysis II. Analysis of chicken manure,biooils, and char by curie-point pyrolysis-gas chromatography/mass spectrometry (Cp Py-GC/MS)

The initial chicken manure and the three fractions derived from it by fast pyrolysis, that is, the two biooils Fractions I and II as well as the residual char were analyzed by Curie-point pyrolysis-gas chromatography/mass spectrometry (Cp Py-GC/MS). The individual compounds identified were grouped into the following six compound classes: (a) N-heterocyclics; (b) substituted furans; (c) phenol and substituted phenols; (d) benzene and substituted benzenes; (e) carbocyclics; and (f) aliphatics. Of special interest were the relatively high concentrations of N-heterocyclics in biooil Fraction II which was obtained in the highest yield and had the highest calorific value. Prominent N-heterocyclics in biooil Fraction II were methyl-and ethyl-substituted pyrroles, pyridines, pyrimidine, pyrazines, and pteridine. Also noteworthy was the high abundance of aliphatics in biooil Fraction I and the char. The alkanes and alkenes in biooil Fraction I ranged from n-C₇ to n-C₁₈ and C_7:1 to C_18:1, respectively, and those in the char from n-C₇ to n-C₁₉ and C_7:1 to C_19:1, respectively. The N-heterocyclics in the two biooil Fractions came from the chicken manure, from proteinaceous materials during fast pyrolysis or were formed during the fast pyrolysis manure conversion by the Maillard reaction which involved the formation of N-heterocyclics by amino acids interacting with sugars.     

Determination of PCDDs and PCDFs in different animal feed ingredients

As result of a study to control feedstuff, analyses were carried out to evaluate the contamination caused by PCDDs and PCDFs in different animal feed ingredients. Thirty two samples were selected, including ingredients of animal and mineral origin. For samples of mineral origin, some additives widely employed as binder and anticaking agents, such as bentonite, damoline, kaolin, magnesite, sepiolite and zeolite were selected. And, for ingredients of animal origin, samples of hemoglobin, animal fat, fish oil, fish meal and meat and bone meal were analyzed. The levels ranged from 0.52 to 9.08 pg WHO-TEQ/g fat for samples of animal origin, and from 0.05 to 460.59 pg WHO-TEQ/g for samples of mineral origin. The higher concentrations were observed for the kaolin samples that presented high levels of dioxin contamination.     

Comprehensive study on dioxin contents in binder and anti-caking agent feed additives

Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were determined in some additives widely employed as binder and anti-caking agents in feedstuffs, such as kaolin, bentonite, zeolite, etc. with an special attention on sepiolite samples. Owing to their physico-chemical properties, the little information of these materials reported in the literature, the variability of PCDDs/PCDFs found in a preliminary evaluation and the absence of reference materials highlighted further research needed. Therefore, an extensive study on the analytical procedures based on the classical methods was performed with sepiolite samples. The study includes evaluation of reproducibility and repeatibility. To this end, a series of intra-day and nine inter-day analysis were made. The methodolgy was also assessed against the sample size and series of 12.5, 25, 37.5 and 50 g were analyzed. In all cases, the results confirmed good correlation with the parameters evaluated.