Depletion study of PCDD/Fs and dioxin-like PCBs concentrations in contaminated home-produced eggs: preliminary study.

Dioxins (PCDD/Fs) and polychlorinated biphenyls (PCBs) are ubiquitous environmental contaminants. The contamination of food products with dioxins and PCBs is a well studied issue, because food is generally considered the major source of dioxin intake for humans. In Italy, the Regional Monitoring Plan (part of the national residue monitoring plan) used in the field for 2009 has also included the control of environmental pollutants in small egg producers. Following an irregular result, 12 laying hens were transferred into a laboratory controlled environment. Eggs were collected for 60 days and they were weekly analysed for the evaluation of dioxins, dioxin-like PCBs (DL-PCBs), and non-dioxin-like PCBs (NDL-PCBs, six congeners) levels. The dioxins and PCBs contents were determined, according to EPA methods, by gas chromatography ic determination coupled with high resolution mass spectrometry (HRGC-HRMS). The content of PCDD/Fs, DL-PCBs and NDL-PCBs was evaluated weekly by mean from week to week. The concentration of dioxins was lower than DL-PCBs (2.5 pg TEQ g(-1) of fat against 4.5 pg TEQ g(-1) of fat), but we observed the same depletion trend for both pollutants. On the opposite, NDL-PCBs had a different course: we noted there was an increase between weeks 6 and 7, but the mean levels remained very low (about 20 ng g(-1) of fat). The dioxins, and sum of dioxin and DL-PCBs concentration were below the fixed European limits (i.e. 3 pg TEQ g(-1) of fat for dioxins and 6 pg TEQ g(-1) of fat for sum of dioxins and DL-PCBs), beginning from the 3rd week of trial.

Estimation of PCDD/F and PCB detoxification rates in contaminated Tapes philippinarum in the Lagoon of Venice.

This work presents the results of a short-term natural detoxification experiment carried out with the contaminated Manila clam (Tapes philippinarum), an edible bivalve species subjected to intense exploitation in the Venice Lagoon. The concentrations of seventeen PCDD/F congeners and twelve dioxin-like PCBs were determined in sediments as well as T. philippinarum specimen sampled in a lagoon area contaminated by industrial pollution. Clam specimen were then transplanted and reared in an area of low contamination. Concentrations of PCDD/Fs and PCBs in clam flesh were determined from samples collected after 10, 20, 30, 45, 60 and 120 days from redeployment. The results show a very rapid decrease of pollutant concentrations towards asymptotic values. Due to rapid decrease, the estimated first-order decay constants were statistically significant (p

Monitoring of polychlorinated dibenzo-p-dioxins and dibenzofurans, dioxin-like PCBs and polycyclic aromatic hydrocarbons in food and feed samples from Ismailia city, Egypt.

Concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyl (PCBs) and polycyclic aromatic hydrocarbons (PAHs) have been determined using GC/HRMS in food (butter, seafood and meat) and feed samples (chicken, cattle and fish) purchased from Ismailia city, Egypt. PCDD/F concentrations in food samples ranged between 0.12 and 3.35 pg WHO TEQ/g wet w, while those in feed samples were between 0.08 and 0.2 pg WHO TEQ/g dry w. Levels of PCB TEQ ranged from 0.14 to 3.2 pg/g wet w in the food samples. The feed samples have an average of 0.35 pg PCB TEQ /g dry w. In this study, butter samples showed the highest contamination levels of PCDD/Fs and PCBs. The PCBs contribution to the total TEQ was on average 63% in seafood and on average 49% for meat and butter. The highest contamination levels of PCDD/Fs and PCBs were found in butter samples. The butter TEQ content is several times higher than that reported in all EU countries and exceeded the EU limits, while the PCDD/F levels in seafood and the feed samples is far below the current EU limit. Generally, congener profiles in the food samples reflect the non-industrialized nature of the city and suggest solid waste burning as a significant source of emission. Nevertheless, the profiles for butter suggest an impact from various sources. In the case of the sum of 16 PAH contamination levels in food samples were in the range of 11.7-154.3 ng/g wet w and feed samples had a range of 116-393 ng/g dry w. Benzo(a)pyrene (BaP) has been detected in the range of 0.05-3.29 ng/g wet w in the food samples; butter showed the highest contamination which exceeded the EU standard set for fats and oil. Fingerprints of PAHs suggested both petrogenic and pyrolytic sources of contamination.

Dietary intake of dioxins and dioxin-like PCBs, due to the consumption of dairy products, fish/seafood and meat from Ismailia city, Egypt.

Although dietary intake studies have been carried out extensively in most developed countries, to evaluate the health risks of PCDD/Fs and DL-PCBs, no data of this kind exists for Egypt. In this study, concentrations of PCDD/Fs and DL-PCBs were measured using HRGC/HRMS in the most contributing foodstuffs (dairy products, fish/seafood, and meat) randomly collected from Ismailia city, Egypt. The dietary intake of PCDD/Fs and DL-PCBs were subsequently determined, and compared with the most recent studies. To provide a primary estimation of the whole TEQ intake in Egypt if all the main food categories included, an estimation of the dietary intake (based on EU data) for some important and non-measured groups (cereals, vegetables/fruits, eggs and milk) was carried out. The calculated dietary intake based on the WHO assumption of 60 kg bw ranged from 3.69 to 4.0 pg WHO-TEQ/kg bw/day for PCDD/Fs and from, 6.04 to 6.68 pg WHO-TEQ/kg bw/day, if DL-PCBs were included. PCBs intake contributed about 40% of the total TEQ intake. Dairy products (mainly cheese) were the main contributor to the intake of PCDD/Fs (89%), while fish/seafood and meat have more or less the same percent share (5.4%). The dairy products contamination was the reason for our elevated dietary intake, as the content of PCDD/Fs and DL-PCBs is several times higher than in all the developed countries. The total intake (PCDD/Fs+DL-PCBs) due to consumption of dairy products, fish/seafood and meat, is close to that reported in EU countries at the beginning of 1980s, but much higher than all those mentioned in all the recent reports, and higher than the maximum WHO TDI of 4 pg TEQ/kg bw/day. A recalculation of the dietary intake to include not only our measured data but also the data for the non-measured groups, yielded a total intake in the range of 4.06-6.38 pg TEQ/kg bw/day for PCDD/Fs and a range of 6.59-9.98 pg TEQ/kg bw/day for total including PCBs. Results show that cereals and vegetables/fruits contribute significantly to PCDD/Fs TEQ intake in Egypt and play a more important role than fish/seafood and meat. This is the case even though the intake for cereals and vegetables/fruits based on EU data.

Measurement of atmospheric deposition of polychlorinated dibenzo-p-dioxins and dibenzofurans in the Lagoon of Venice, Italy.

Data on atmospheric fall-out of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) were provided by collecting bulk deposition in four stations inside the Lagoon of Venice. A total of 44 monthly samples was collected during the period July 1998-July 1999 in one site near an industrial area (Porto Marghera), one site in the city of Venice, and two sites in the southern- and northernmost ends of the Lagoon. Fluxes of PCDD/Fs were between 0.1 and 470 pg m(-2) d(-1), corresponding to 0-9.2 pg of 2,3,7,8-TCDD equivalents (TEQ) m(-2) d(-1), with a gradient increasing from remote to urban/industrial stations. Thus, annual deposition of PCDD/Fs to the Lagoon (total area=550 km2), calculated with various methods, turned out to be approximately 12 g, corresponding to approximately 400 mg TEQ. Significant differences were found among the stations, with a clear fingerprinting signature (PCDF/PCDD>1) of the deposition collected near Porto Marghera, and a reversed pattern (PCDF/PCDD<1) in the rest of the Lagoon, which pattern was similar to the sediments collected in the same locations. Lastly, the amount of bulk sigmaTEQ of all stations was compared with the guide values for dioxins in depositions proposed by De Fré et al. [Organohalogen Compounds 45 (2000) 324].

Polychlorinated biphenyls in sediments of the Venice Lagoon.

Twenty-four surficial sediment samples, representing different environments within the Venice Lagoon, were analyzed for polychlorinated biphenyls (PCBs) in order to assess degrees of pollution, sources, areal distribution, and potential risk for the environment. Concentrations in surficial sediments range from 2 to more than 2049 microg kg(-1) dw. The maximum is probably due to the discharge of industrial wastes into the Brentella Canal, within the first Industrial Area. Lagoon samples are 11-205 times less contaminated, being influenced by pollutants stored in the canals only occasionally. Congener profiles distinguish PCBs in two main categories. The baseline pollution is probably due to a variety of sources within the lagoon system, whereas less chlorinated PCBs were discharged into the Brentella Canal. Our estimates suggest that, due to high concentrations, toxic equivalents (TEQs) of PCBs are comparable to those relative to PCDD/Fs for the least contaminated samples, whereas they are lower in case of heavy PCDD/F contamination.

Dioxins in the Venice lagoon: Present situation, projects and recovering hypotheses.

Venice is famous around the world for its uniqueness and architectural splendours, arts and the history of the "Serenissima Repubblica", as it was known in the past, but few are aware that Venice economy is strongly dependent on the industrial activities based mainly on the adjacent Porto Marghera area. For many years, the lagoon that physically separates the city from the dry land has avoided association between the concern connected with the pollution derived from these industrial activities and the public perception of Venice. Since 1995, dioxins have appeared as a lagoon contaminant, and their presence, at such a level requiring immediate "in depth" studies and interventions, has been fully realized for decades.

Polychlorinated biphenyl pollution caused by resuspension of surface sediments in the lagoon of Venice.

A mechanical device was used to reproduce in the laboratory the sediment resuspension caused by tidal currents and wind waves in the lagoon of Venice. Shear stresses comparable to those observed in the field were applied to the sediment surface. Series of experiments were run at 6.6 and 9.0 dyn/cm2. The concentration of polychlorinated biphenyls (PCBs) were determined in the sediments and resuspended particulate matter by means of gas chromatographic techniques. At the two different stresses, particulate matter with different grain size and different concentrations of PCBs was resuspended. However, no significant differences were observed in the amounts of PCBs mobilized per litre of water. In fact, by increasing the applied stress, coarser particulate matter was resuspended with a lower concentration of PCBs per unit of dry weight.