Status of the PCDD and PCDF contamination of commercial milk caused by milk cartons

Within the scope of this study, possible migration of polychlorinated dibenzodioxins and -furans (PCDDs/PCDFs) from cartons (produced using bleached cardboard) into cow's milk was investigated. Three different types of carton were examined. The milk samples were taken at different times of storage and analysed for PCDDs/PCDFs. In contrast to a similar study carried out in 1990, the I-TEQ-results of all cartons analysed may be considered very low. No significant migration of toxic (2,3,7,8-chlorine-substituted) PCDDs/PCDFs could be observed. This is due to the very low PCDD/PCDF concentrations in modern cardboards as a result of the elemental chlorine-free (ECF) bleaching processes used. As far as the milk samples are concerned, no influence of the cardboards (according to the I-TEQ data) could be ascertained. I-TEQ concentrations in milk did not noticeably change during storage times of three, six and eight days. The I-TEQ-data obtained for all milk samples was found to be in the range typical of background concentrations in cow's milk in Germany. Although 1,2,7,8-TCDF is not included in the calculation of the TEQ (no 2,3,7,8-chlorine-substitution), analysis of this congener in cardboard samples was also carried out as a matter of general interest for cardboard investigations and an indicator of pulp bleaching with free chlorine.     

Formation of PCDD/PCDF

One option of recycling used contaminated packaging is to recover its high energy content. This can be performed in a normal multi-fuel power plant by co-combustion of packaging-derived fuel (PDF) or refuse-derived fuel (RDF) with fossil fuels, such as coal or peat. This work includes the results of 17 co-combustion tests and an evaluation of the results by the Principal Component Analysis (PCA) and the Partial Least Squares Projections to Latent Structures (PLS). PCA and PLS calculations showed that especially Pb, but also Cr, and Cu correlated with lower chlorinated furans (PCDFs) in the fly ash. Correlation between Sn and lower chlorinated dioxins (PCDDs) in the fly ash was also noticed. CO and PAH emission in the flue gas correlated with total PCDD/Fs in the flue gas. In a real full-scale combustion process, a single parameter in fuel, flue gas or a combustion parameter did not provide a guide to PCDD/F formation or to a level of the total PCDD/F emission, but correlations between different parameters and PCDD/Fs could be found. Although PDFs and RDF had catalytic heavy metals and chlorine, the co-combustion results showed that they can be co-combusted with peat and coal in a fluidized-bed boiler at least up to 26 % with very low total PCDD and PCDF emissions.     

Sources and fate of PCDD and PCDF

PCDD and PCDF were found in urban air particulates from St. Louis and Washington, D.C., and in sediments from the Great Lakes and Siskiwit Lake, Isle Royale. The similarity between the PCDD and PCDF found in air particulates and sediment samples and the presence of PCDD and PCDF in sediment from Siskiwit Lake (a location which can receive only atmospheric inputs) suggest that these compounds are emitted to the atmosphere from combustion sources. The historical input of PCDD and PCDF to dated sediment cores shows a strong increase since 1940, and this suggests that the incineration of chlorinated organic compounds is an important source of PCDD and PCDF to the environment.     

PCDD, PCDF, AND PCB concentrations in human milk from two areas in Finland

Concentrations of 17 toxic 2,3,7,8-chlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and of 36 polychlorinated biphenyl congeners (PCBs) were analyzed from 167 randomly sampled human milk samples from Southern (77 samples) and Eastern (90) Finland. The level of PCDD/Fs and PCBs in human milk in Southern Finland was about 25% higher than those from Eastern Finland. The level of PCDD/Fs in human milk in Finland was the same as in Sweden, 30–50 % lower than in milk from Central Europe but about 45% higher than values from Norway or Russia. The PCB concentrations in Southern Finland were at the same level as in the Netherlands, and in Eastern Finland at the same level as in Norway. The levels of PCDD/Fs and PCBs decreased with increasing number of children: the third child was exposed to about 70% of the amount of PCDD/Fs and PCBs as compared with the first child, and the eighth to tenth child to about 20%. The congener patterns of PCDD/Fs and PCBs in Finnish human milk were similar to the countries of Central Europe, however, the levels of penta- and heptachlorinated furans were slightly higher than in milk from other countries.     

Formation characteristics of PCDD and PCDF during pyrolysis processes

In recent years, pyrolysis processes have become technologies developed to industrial scale and discussed as alternatives to the existing waste combustion technology. However, little information is published regarding PCDD/F formation characteristics during pyrolysis processes. Two common shredder fractions – industrial light shredder (ILS) and refrigerators (REF) – both with high chlorine and copper content were pyrolysed for this pyrolysis study using a pilot plant with a capacity of 100 kg/h. At oxygen concentrations below 2% and temperatures between 430°C and 470°C, considerable amounts of PCDD/F were formed during the pyrolysis. More than 90% of total TEQ was found in the oil fraction (gas phase). The PCDD/PCDF ratio and the homologue pattern differed significantly from those formed during waste incineration. Considering mono- to octachlorinated congeners, up to 400 times more PCDF were formed compared to PCDD. For the investigated pyrolysis conditions, the formation of low chlorinated congeners was highly favoured. The distribution of TEQ within the individual congeners were very similar in all investigated runs. More than 80% of total TEQ stem from 2,3,7,8-substituted T₄CDF and P₅CDF. The isomer pattern, however, did not show significant differences compared to the common waste incineration pattern suggesting that the basic formation routes are similar.     

Destruction of PCDD/PCDF by non-thermal methods

The physical, chemical and biological processes for the destruction of PCDD/PCDF and the treatment of dioxin-contaminated wastes are reported. Tests and their results, carried out in laboratories and pilot plants with PCDD and similar compounds, are discussed. The development and testing of suitable catalysts for the chemical conversion of dioxins and other chlorohydrocarbons are examined. The application conditions, the necessary pretreatments of wastes, and the destruction efficiencies of the different methods are examined. A technical, economic, and environmental assessment according to the tested results is considered.     

PCDD, PCDF, PCB and PBDE concentrations in breast milk of mothers residing in selected areas of Slovakia

The concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorinated biphenyls (dl-PCBs) and polybrominated diphenylethers (PBDEs) in 33 breast milk samples collected in 2006-2007 from primipara mothers close to four industrial areas of Slovak Republic were determined. The total PCDDs/PCDFs and dl-PCBs expressed as TEQ based on WHO TEFs 1998 in breast milk samples varied from 5.0 to 51.8 pg g⁻¹ fat (median: 13.1 pg g⁻¹ fat; mean: 18.0 pg g⁻¹ fat). The measurements of seven PBDE congeners (IUPAC No. 28, 47, 99, 100, 153, 154, and 183) were performed for the first time in human milk from Slovakia. PBDE levels ranged between 0.22 and 1.62 ng g⁻¹ fat, with median and mean value of 0.43 ng g⁻¹ fat and 0.57 ng g⁻¹ fat respectively. No statistically significant differences were observed between studied areas in total PBDE concentrations.Furthermore, this study presents first results concerning the daily intake (DI) of PCDDs/PCDFs and dioxin-like compounds for the most vulnerable breast-fed infant population in Slovakia. The total PCDD/PCDF and dl-PCB DI for an infant during the first 2 months of life was estimated in a range from 14.4 to 230 pg TEQ kg⁻¹ b.w., with a median value of 58.9 pg TEQ kg⁻¹ b.w.. The DI values substantially exceeded the tolerable daily intake (TDI) 1-4 pg TEQ kg⁻¹ b.w. recommended by WHO. The dietary infant intake concerning PBDEs was estimated to be between 0.69 and 7.1 ng kg⁻¹ b.w. d⁻¹, with median value of 1.7 ng kg⁻¹ b.w. d⁻¹.     

The emission inventory of PCDD/PCDF in Taiwan

Establishment of a country or region-based dioxin inventory was considered a crucial step toward elimination of worldwide dioxins/POPs contaminations, although no harmonized method for the preparation of an inventory is available at present. In this study, we used limited data and information to generate an inventory of dioxin emissions from some major sources in Taiwan. A total of 67.25 g I-TEQ of dioxins released annually was estimated. Unlike most of the industrialized countries, municipal waste incineration is not the highest contributor for dioxins released into the atmosphere. In contrast, secondary copper smelting accounts for more than 39% of the total dioxin emissions, and is higher than those from all waste incinerators combined (23.7%). Cement kilns and electric arc furnaces for steels also produced significant portion (both >10%) of dioxins into the environment, followed by secondary aluminum smelting (6.53%), industrial oil combustion (5.02%) and power plants fueled by coal (5.01%). Other known sources are either insignificant with respect to their dioxin emissions or not included in this inventory due to lack of information or uncertainty of the results. Data presented in this report provide a general picture of dioxin emissions in Taiwan, but were mostly based on less reliable or representative information, especially with respect to emission factors from different emission sources. It is necessary to establish background information relative to our own environment at present. Upon available, the inventory should be updated accordingly for proper environmental management on dioxins.     

Comparison of PCDD/PCDF levels in soil, grass, cow''s milk, human blood and spruce needles in an area of PCDD/PCDF contamination through emissions from a metal reclamation plant

When in the vicinity of a metal reclamation plant in Tyrol, Austria, increased PCDD/PCDF levels were found in soil and spruce needles, the extent of grass contamination as well as the PCDD/PCDF content in milk of cows fed with hay from this area was determined. The milk samples showed a significant increase in PCDD/PCDF levels compared to control samples. In a blood sample of a farmer a significant increase in PCDD/PCDF levels was found. Correlations in PCDD/PCDF levels between soil, spruce needles, grass, cow's milk and human blood will be presented.     

Dioxins and furans in the Jordanian environment part 2: Levels of PCDD and PCDF in human milk samples from Jordan

Thirty individual human milk samples were gathered from five main towns in Jordan. They were mixed to six pooled samples and analyzed for PCDD and PCDF. All examined samples were contaminated with 1,2,3,4,6,7,8-HeptaCDD (3.2 – 96.0 n&/kg fat) and OctaCDD (29.0 – 147 ng/kg fat). The calculated TEQ (BGA)-values range between 026 and 60.32 ng TEQ/kg fat, which are all above the calculated tolerable concentration of 019 ng TEQ/kg milk fat.     

PCDD/PCDF,chlorinated pesticides and PAH in Chinese teas

Four samples of Chinese tea (two green teas, and two brick teas) were analyzed for their concentrations of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/PCDF), chlorinated pesticides and PAH. The infusions prepared from these teas were also analyzed for PCDD/PCDF. The levels of DDT and its metabolites in tea leaves were within the safety limit of 0.2 mg/kg. Rather high levels of total PAH were obtained in brick tea (1048–1162 mg/kg), when compared with green tea (497–517 mg/kg). In terms of PCDD/PCDF, the concentrations of green tea and brick tea differed by a factor of 16, while the concentrations of all infusions were within a factor of 2. The dioxin concentrations in green tea leaves can be explained through uptake of atmospheric PCDD/PCDF. The higher concentrations in the brick tea leaves are due the longer exposure time, and to certain extent, the use of old leaves, branches and roots when making the tea, and additional components such as soil particulates through contamination. Certain Chinese populations drinking a large amount of brick tea (>3 l per day) indicated that individuals of these populations consume more tea than Europeans or North Americans result in a comparably higher intake of PCDD/PCDF. Tea consumption can attribute to up to 10% of the TDI recommended by WHO (only PCDD/PCDF considered, no PCB analyzed).     

PCDD/PCDF emissions from small firing systems in households

This report presents results of emission measurements of polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) in the flue gas of seven oil, nine gas, and two wood firing systems under laboratory conditions. The burn rate of the combustion was in the range of the rated useful heat output. Two additional test series varied the amount of combustion air and thus the heat output. The PCDD/PCDF emissions for oil- and gas-fired boilers are in the range of 0.0020-0.0142 ng I-TEQ/m3 (referring to 3% O2 in the dry flue gas). No correlation between the combustion technique and the PCDD/PCDF emissions could be established. In the tests with the wood-fired furnaces PCDD/PCDF concentrations in the flue gas ranging from 0.014 to 0.076 ng I-TEQ/m3 (referring to 13% O2 in the dry flue gas) were found. A significant correlation between the firing rate of the heating insert and the measured PCDD/PCDF concentrations was found. On examination of three typical 2,3,7,8-CDD/CDF congener profiles, a comparable pattern could be observed with natural gas and light fuel oil. The congener distribution for wood combustion is considerably different.     

Atmospheric baseline levels of PCDD and PCDF in the region of Oporto

An external monitoring plan (EMP) is being implemented in the region of Oporto, Portugal, to follow the potential effects of a future incinerator of municipal solid waste. Polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/PCDF) were measured during 1998 and the first semester of 1999, prior to the working up of the incineration unit. The baseline levels obtained through this intensive monitoring work are presented and discussed in the present paper.     

HCB,PCB, PCDD and PCDF emissions from ships

Since current estimates of hexachlorobenzene (HCB), polychlorinated biphenyls (PCB), dioxins (PCDD) and furans (PCDF) from ships are based on a relatively limited and old data set, an update of these emission factors has been outlined as a target towards improved Swedish emission inventories. Consequently, a comprehensive study was undertaken focusing on these emissions from three different ships during December 2003 to March 2004. Analyses were performed on 12 exhaust samples, three fuel oil samples and three lubricating oil samples from a representative selection of diesel engine models, fuel types and during different “real-world” operating conditions.The determined emissions corresponded reasonably well with previous measurements. The data suggest however that previous PCDD/PCDF emission factors are somewhat higher than those measured here. As expected the greatest emissions were observed during main engine start-up periods and for engines using heavier fuel oils. Total emissions for 2002, using revised emission factors, have been calculated based on Swedish sold marine fuels and also for geographical areas of national importance. In terms of their toxic equivalence (WHO-TEQ), the PCDD/PCDF emissions from ships using Swedish fuels are small (0.37–0.85 g TEQ) in comparison to recent estimates for the national total (ca. 45 g TEQ). Emissions from other land-based diesel engines (road vehicles, off-road machinery, military vehicles and locomotives) are estimated to contribute a further 0.18–0.42 g TEQ. Similarly, HCB and PCB emissions from these sources are small compared to 1995 national emission inventories.     

Intra- and inter- laboratory variability in paper industry PCDD/PCDF analysis

Studies were conducted to quantify variability for pulp industry wastewater effluent, pulp and sludge analyses. Intralaboratory variability studies indicated that there is a potential for greater between batch variability in results than for within a batch. Intralaboratory relative standard deviations for replicate analyses ranged from 6% to 60%. Interlaboratory studies, using standard reference materials showed relative standard deviations from 4% to 135%. There appeared to be little dependance of variability on concentration, suggesting matrix effects were very important. In general, effluent variability was greater than observed for pulps or sludges. Analysis of reference standards indicated that 13% to 17% variability can be attributed to differences in calibration standards. A limited study of full congener PCDD/PCDF analysis variability showed it to be greater than observed for TCDD/TCDF.     

Control of PCDD/PCDF emissions from refuse-derived fuel combustors

This paper presents preliminary results of performance tests conducted at the Mid-Connecticut Refuse-Derived Fuel Facility in February 1989. The objectives of these performance tests were to evaluate the effects of combustion and flue gas cleaning process conditions on air pollution emissions and residue properties.     

Investigation of different treatment techniques for PCDD/PCDF in fly ash

A number of different pretreatment and extraction procedures were compared with regard to recovery of PCDD/PCDF from fly ash. Highest results were obtained using an acid digestion with excess dilute HCl, followed by freeze drying of the residue and hot extraction by toluene.     

Thermal behavior of PCDD/PCDF in fly ash from municipal incinerators

The effect of thermal treatment of fly ash on the behaviour of PCDD/PCDF was studied in the range between 120 and 600° C. Annealing at 300° C (2 hrs) resulted in an increase of PCDD/PCDF concentration by a factor of 10 to 15. At 600° C degradation to concentrations below 0.1 ng/g is observed.     

PCDD/PCDF congener profiles in soil and herbage samples collected in the vicinity of a municipal waste incinerator before and after pronounced reductions of PCDD/PCDF emissions from the facility

Congener profiles are the fractional distribution of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) congeners in an environmental release, or in an environmental or biological sample. In 1999, an adaptation to the EU legislation on pollutant emissions from the stack was carried out in an old municipal solid waste incinerator (MSWI) from Montcada (Barcelona, Spain). The main goal of the present study was to determine if the environmental PCDD/F levels in the area under direct influence of the facility were mainly due to PCDD/F emissions from the plant. For this purpose, soil and herbage samples were collected near the MSWI before (1998) and after (2000) the technical improvements were performed. PCDD/F congener profiles were determined and compared with those from samples collected in a suburban area of Constantí (Tarragona, Spain) outside of direct emissions from any MSWI. The results of the present study suggest that the MSWI here assessed is not the main responsible for the environmental PCDD/F concentrations in the area under evaluation. Other PCDD/F emission sources in the same area seem also to have a notable impact on the atmospheric levels of these pollutants.