Contamination levels and congener distributions of PCDDs, PCDFs and Co-PCBs in several fast foods in Japan

We determined the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and coplanar polychlorinated biphenyls (Co-PCBs) in three types of fast foods [(1) seventeen hamburgers and two hot dogs, (2) six portions of fried potatoes and (3) three chicken products] obtained from fast food shops or convenience stores in Japan. All samples tested showed low toxic equivalent quantity (TEQ) levels of dioxins in the range of 0.001-0.083 pg-TEQ/g wet weight (0.006-0.053 pg-TEQ/g for hamburgers and hot dogs, 0.001-0.083 pg-TEQ/g for fried potatoes and 0.053-0.065 pg-TEQ/g for chicken products). The congener profile in hamburgers and hot dogs suggested that the total TEQ was mainly determined by Co-PCBs, especially by 3,3',4,4',5-PeCB (#126), which accounted for 44% of the total TEQ value. Findings for animal foods such as beef and cheese were consistent with this result. For fried potatoes, PCDD/Fs accounted for 94% of the total TEQ value, and 2,3,4,7,8-PeCDF accounted for 32% of PCDD/Fs. Dioxins in the chicken products consisted of 3,3',4,4',5-PeCB (#126) and 1,2,3,7,8-PeCDD, which accounted for 23% and 21% of the total TEQ, respectively. If an adult (50 kg weight) eats 150 g of hamburger, 100 g of potatoes and 150 g of chicken, the daily intake is estimated to be 0.299 pg-TEQ/kg b.w./day using the average values (0.022, 0.028 and 0.059 pg-TEQ/g, respectively) obtained in this study. This value corresponds to 7.5% of the tolerable daily intake (TDI) for PCDD/Fs and Co-PCBs in Japan.     

Estimation of daily intake of PCDDs, PCDFs and Co-PCBs from baby foods

A study of the dietary intake of dioxins, consisting of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and coplanar polychlorinated biphenyls (Co-PCBs) through baby foods in the metropolitan Tokyo area was carried out. The samples were homemade baby foods prepared by the total diet-market basket method and baby foods (mainly commercial items) prepared by the duplicate portion method. The daily intake of dioxins per kg of body weight from baby foods in each weaning stage for the case of half intake of homemade baby foods and the other half of mainly commercial items was 0.32 pg TEQ/kg/day in the early stage, 0.45 pg TEQ/kg/day in the intermediate stage, 0.58 pg TEQ/kg/day in the late stage and 1.25 pg TEQ/kg/day in the completed stage. While the daily intakes increase with the weaning progress, they were less than the tolerable daily intake (TDI) of 4 pg TEQ/kg/day for dioxins established in Japan. Dioxins were mainly taken through formula milk in early stage of weaning period, but then were taken through protein-based foods in the subsequent weaning stage.     

Levels and congener distributions of PCDDs, PCDFs and Co-PCBs in Japanese retail fresh and frozen vegetables

To evaluate dioxin contamination in retail vegetables, congener analyses of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and coplanar polychlorinated biphenyls (Co-PCBs) were performed on sixty varieties of fresh vegetables including cereals and mushrooms, obtained from Japanese supermarkets in 2002. The toxic equivalent quantity (TEQ) levels for dioxins in samples ranged from < 0.001 to 0.089 pg-TEQ/g wet weight, when undetected and trace were taken as zero. Among the samples, dioxins were generally detected in green leafy vegetables. The highest TEQ value was for mulukhiya (0.089 pg-TEQ/g), followed by spinach and komatsuna (Japanese mustard spinach) (0.077 and 0.074 pg-TEQ/g, respectively). Additionally, the dioxin levels in seventeen varieties of frozen vegetables were also determined, and showed TEQ values ranging from < 0.001 to 0.080 pg-TEQ/g. The total TEQ in commercial vegetables mainly reflected the levels of 1,2,3,7,8-PeCDD, 2,3,4,7,8-PeCDF and 3,3',4,4',5-PeCB (#126) (the sum of them represented 63% of the total TEQ).     

Contamination levels of PCDDs, PCDFs and CoPCbs in fish oils used as raw materials for margarine and shortening and retailed fish

Toxic equivalent (TEQ) levels of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/DFs) and coplanar polychlorinated biphenyls (CoPCBs) were analyzed in both crude (n = 5) and refined-hardening fish oils (n = 2), which are used in part as the raw materials of margarine and shortening, and in some retailed fish (n = 6), which may be similar to those used as sources of fish oil. PCDDs/DFs-TEQ levels ranged from 0.1 to 13.5 pg TEQ/g fat weight in crude fish oils, from 0.5 to 1.6 pg TEQ/g fat weight in refined-hardening fish oils, and ranged from 1.4 to 31.2 pg TEQ/g fat weight in retailed fish. The ranges of PCDDs/DFs-TEQ in crude fish oils, in refined-hardening fish oils and in retailed fish overlapped each other. In addition, CoPCBs-TEQ levels ranged from 4.9 to 19.6 pg TEQ/g fat weight in crude fish oils, from 0.2 to 1.4 pg TEQ/g fat weight in refined-hardening fish oils, and from 2.7 to 165.8 pg TEQ/g fat weight in retailed fish. TEQ levels of CoPCBs in refined-hardening fish oils were much lower than those in crude fish oils and in retailed fish. This was due to the lower concentrations of less-chlorinated congeners in refined-hardening fish oils, as compared to those in crude fish oils and retailed fish. It appears that less-chlorinated PCBs congeners in refined-hardening fish oils are partly removed during the refining process.     

Stability of arsenobetaine levels in manufactured baby foods

The stability of arsenobetaine in baby foods under different experimental conditions is evaluated. Total arsenic was analyzed by electrothermal atomic absorption spectrometry, and the speciation of arsenicals was carried out by coupling liquid chromatography to hydride generation-atomic absorption spectrometry. The highest arsenic levels in the analyzed baby foods corresponded to those containing plaice (2 to 3 microg/g). The speciation data indicated that arsenobetaine, a nontoxic species, was the only arsenical present in the baby foods analyzed at levels between 0.2 and 3 microg/g. Two different procedures for extracting arsenicals from baby foods, involving a water-methanol-chloroform mixture and enzymatic hydrolysis, were tested, and similar results were obtained. Furthermore, the arsenobetaine levels remained unchanged when the baby foods were stored for different times or when the samples were freeze-dried, thus confirming the stability of arsenobetaine and the nonappearance of other arsenic species by interconversion. The reliability of the procedure was checked by analyzing a certified reference material.     

Nutritional evaluation of some commercial baby foods consumed in Pakistan

The nutritive value of some commercial baby foods commonly consumed in Pakistan was evaluated by means of chemical and biological assays. The protein content of milk based formulas and cereal-milk blends ranged from 13.3–26.0 and 11.1–13.2%, respectively. The fat content was highest (27%) in P-7f and was lowest (3%) in Robinson Baby Food. The available carbohydrates in milk based formulas were lower (44.1–59.9%) than cereal-milk blends (71.5–77.7%). The highest content of ash (5.6%) was found in Ostermilk. The metabolisable energy (ME) values ranged from 428–473 and 349–391 kcal, respectively, in milk based formulas and cereal-milk blends. The net protein utilisation (NPU) values of milk based formulas varied between 0.68 and 0.75 and NPU values of cereal-milk blends ranged from 0.69 to 0.71. The protein quality of baby foods was compared with the standards and the low NPU values reflected the influence of the processing technique.     

Magnification and toxicity of PCBs, PCDDs, and PCDFs in upriver-migrating Pacific salmon

The depletion of lipids associated with pre-spawning migration of Pacific salmon has the potential to magnify concentrations of hydrophobic organic contaminants (HOCs), which elevates risk of toxic effects. We present data from a field study of sockeye salmon (Oncorhynchus nerka) migrating to spawn in Great Central Lake, BC, which demonstrate that pre-spawning migration causes a magnification of PCB, PCDD, and PCDF concentrations in female gonads (1.9-2.5-fold), female soma (3.4-5.6-fold), and male soma (5.6-9.7-fold). We further develop a model of prespawning migration chemical magnification for sockeye salmon stocks as a function of migration distance. This model is shown to be consistent with available empirical data on pre-spawning magnification and predicts magnification factors ranging between 1.4 and 7.9 in gonad and between 1.6 and 10.4 in soma in seven Pacific salmon stocks in British Columbia. Post-migration (prespawning) toxic equivalent dioxin concentrations in roe were measured to be approximately 3 pg/g lipid in salmon from the Great Central Lake sockeye stock and estimated to range between 1.5 pg/g lipid for the shortest-migrating stocks and 7 pg/g lipid for the longest-migrating stocks. Concentrations in certain stocks approach or exceed the concentration of 3 pg/g lipid associated with 30% egg mortality in Oncorhynchus mykiss. This indicates the potential for population-level effects of current contaminant levels. It also suggests that historic contaminant concentrations, which were greater than current concentrations, may have contributed significantly to the decline of certain Pacific salmon stocks in British Columbia.     

Health risks to infants from exposure to PCBs, PCDDs and PCDFs

Global contamination by a variety of anthropogenic persistent organic chemicals, such as dioxins and PCBs, has resulted in human exposure throughout all phases of development. Detectable concentrations of PCBs and dioxins have been found in amniotic fluid, placenta and foetal tissue samples while infants who are breast-fed can obtain blood levels greater than those of their mother's. In two separate food poisoning episodes where infants were exposed in utero to elevated levels of heat-degraded PCBs (PCBs, PCQs, PCDFs), a variety of adverse mental and physical developmental abnormalities have been observed. In additional human cohorts where exposure could be considered as environmental or background, more subtle effects, including lower birth weights, alterations in thyroid hormones and lymphocyte subpopulations and detriments in neurological development, have been consistently seen. In most instances, negative associations were made between in utero exposure to contaminants compared with lactational. Although the observed neurodevelopmental deficits have been described as subtle, there could be unknown consequences related to future intellectual functionality. Current regulatory efforts should focus on identification and control of environment and food chain contamination as in utero exposure is a direct consequence of the accumulated maternal body burdens.     

PCDDs, PCDFs, and coplanar PCBs in albatross from the North Pacific and Southern Oceans: levels, patterns, and toxicological implications

Concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and coplanar polychlorinated biphenyls (coplanar PCBs) were determined in five albatross species collected from the North Pacific and Southern Oceans to assess the north-south differences in residue levels, accumulation patterns, and toxic potential. Black-footed and Laysan albatrosses from the North Pacific Ocean contained higher levels of PCDD/Fs and coplanar PCBs than albatrosses from the Southern Ocean, indicating that emission sources of these contaminants were predominant in the northern hemisphere. Residue levels in albatrosses from the remote North Pacific Ocean far from the point source of pollution were comparable to or higher than those in terrestrial and coastal birds from contaminated areas in developed nations, suggesting the specific exposure and accumulation of PCDD/Fs and coplanar PCBs in albatross. The long life span and ingestion of plastic resin pellets by albatrosses could be the plausible explanations for the elevated accumulation of persistent and lipophilic contaminants including PCDD/Fs and coplanar PCBs in these birds. Relative proportions of PCDFs and coplanar PCBs in albatross were higher than those observed in birds inhabiting terrestrial and coastal areas, suggesting that these toxic chemicals may have higher transportability by air and water than PCDDs. Congener patterns of PCDD/Fs in albatross showed less variability as compared to those in terrestrial species, indicating that contamination patterns of PCDD/Fs were similar within the open ocean environment. Contributions of PCDD/Fs to total TEQs in albatrosses from the open ocean were generally lower than those in terrestrial birds, suggesting different toxic potency of PCDD/Fs and coplanar PCBs on animals inhabiting open ocean and terrestrial environment. Whereas albatrosses from southern oceans retained lower TEQ concentrations, possible adverse effects of PCDD/Fs and coplanar PCBs to black-footed and Laysan albatrosses of the North Pacific Ocean may be suspected from TEQ levels.     

Comparison of sulfuric acid treatment and multi-layer silica gel column chromatography in cleanup methods for determination of PCDDs,PCDFs and dioxin-like PCBs in foods

Two typical cleanup methods, sulfuric acid treatment and multi-layer silica gel column chromatography, for the determination of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (dioxin-like PCBs) in seventeen food samples were examined and compared. Vegetables, fruits, cereals, fish, meat and dairy foods were extracted by conventional methods (shaking with acetone/n-hexane or with n-hexane after alkaline treatment). The extracts were cleaned up by sulfuric acid treatment or multi-layer silica gel column chromatography, followed by several column chromatographic steps. Of the samples treated, the vegetable, fruit and cereal samples could be directly applied to the multi-layer silica gel column after extraction. However, the samples containing fats and oils such as fish, meat and dairy foods needed to be treated several times with concentrated sulfuric acid before multi-layer column chromatography, because these samples plugged the column with oily residues. Both cleanup methods gave similar values of isomeric concentrations and showed similar efficiency of purification, and the recoveries ranged from 40 to 120%. These results are considered to provide useful data for the efficient analysis of dioxins in foods which have wide-ranging compositions.     

On-road emissions of PCDDs and PCDFs from heavy duty diesel vehicles

This work characterized emission factors of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDDs/Fs) from on-road sampling of three heavy duty diesel vehicles (HDDVs) under experimental conditions of city and highway driving; idling operation; high (>400 ppm) and low (<5 ppm) sulfur (S) fuels; and high mileage and rebuilt engine testing. Emission factors, homologue profiles, and isomer patterns were compared to determine whether the experimental conditions had an impact on PCDD/F emissions, or whether these conditions were uninfluential in determining a fleet-representative emission factor. For a single HDDV tested under conditions of a high mileage engine, a newly rebuilt engine, and the newly rebuilt engine with low S diesel fuel, emission factors were 0.023 (+/- 0.022), 0.008 (+/- 0.002), and 0.016 (+/- 0.013) ng toxic equivalency (TEQ)/km, respectively. These results may infer some limited condition-specific differences in PCDD/F emissions, but these differences do not appear to have a significant effect on the HDDV emission factor. An older HDDV with mechanical fuel controls resulted in a single test value of 0.164 ng TEQ/km, significantly higher than all other results. Observed differences in emission factors, homologue profiles, and TEQ-related isomer patterns from this on-vehicle sampling and others' tunnel sampling suggest limitations in our present characterization of fleet PCDD/F emissions.     

Quantitation by magnetic resonance imaging of heating of commercial baby foods in glass jars

This study demonstrates how magnetic resonance imaging can be used to quantitate the heating of commercially available baby foods as sold in glass jars either ‘on‐line’ during immersion in warmed water in the scanner's magnet, or ‘off‐line’ following microwave heating. The internal temperature distribution can be measured in 2‐ or 3‐dimensions with a precision of ±1.5 °C compared with fibre optical thermo‐probe measurements. Illustrative examples include jars of Heinz ‘Banana & Apple’, Sainsbury's ‘Organic Banana Rice Pudding’ and Cow & Gate ‘Organic Roasted Vegetable Lasagne’. Localised thermal lags induced by pieces of vegetable in the lasagne were observed during on‐line immersion heating. Importantly, the spatially heterogeneous heating by microwaves demonstrates the need for strong warnings about using microwave ovens for heating baby foods.     

Calcium-promoted catalytic degradation of PCDDs, PCDFs, and coplanar PCBs under a mild wet process

The authors achieved highly efficient degradation of polychlorinated aromatic compounds, including polychlorinated dibenzo-p-dioxins, dibenzofurans, and dioxin-like compounds such as coplanar polychlorinated biphenyls (co-PCBs), which are known as persistent organic pollutants. Degradation was accomplished in 24 h through a simple stirring operation using safe and high workability metallic calcium, which acts as both a scavenger and a reducing agent, and Rh/C catalyst in an alcohol solution under mild conditions in a sealed tube at 25 degrees C without a temperature increase within 0.15 MPa of increasing internal pressure during the reaction. In this system, reductive dechlorination by metallic calcium and catalytic reduction by Rh/C and generated hydrogen gas, without any external addition of hydrogen, exert a synergistic effect on the degradation of chlorinated compounds. Alcohol was used as a proton source and hydrogen, which was generated by a side reaction, causes an increase in the activity of Rh/C catalyst. Through the degradation of 4-chloroanisole in ethyl alcohol, anisole and cyclohexyl methyl ether were obtained in good conversions. Using ethyl alcohol as a solvent, treatment of dioxins and co-PCBs in a solution was markedly effective for degradation to reduce 2806 pg TEQ/ml of initial concentration to 31.8 pg TEQ/ml; its yield was 98.5%. Moreover, degradation in methyl alcohol took place in a 99.3% yield. That concentration ultimately reached 20.3 pg TEQ/ml under a mild wet process. All congeners of dioxins and co-PCBs were degraded in high conversions. In this degradation, lower aliphatic alcohol, such as methyl alcohol, is effective for making a new calcium surface as compared to alcohol with more methylene chains. In addition, it seemed that a higher pressure of hydrogen was easily generated in methyl alcohol, and then catalytic degradation was effectivley influenced.     

Statistical comparison of residential soil concentrations of PCDDs, PCDFs, and PCBs from two communities in Michigan

The University of Michigan dioxin exposure study was undertaken to address concerns that the industrial discharge of dioxin-like compounds in the Midland, MI area had resulted in contamination of soils in the Tittabawassee River floodplain and downwind of the incinerator. The study was designed in a rigorously statistical manner comprising soil measurements of 29 polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and polychlorinated biphenyls (PCBs) from 766 residential properties, selected probabilistically, in the Midland area and in Jackson and Calhoun Counties (Michigan) as a background comparison. A statistical comparison determined that the geometric mean toxic equivalent (TEQ) levels in samples from the target populations were statistically significantly above background. In addition, the probabilities of being above the 75th and 95th percentiles of background were also greater. Congener contributions to the TEQ were dominated by 2,3,4,7,8-PeCDF and 2,3,7,8-TCDF in the floodplain and by 2,3,7,8-TCDD in the incinerator plume. However, PCB 126 was the top congener contributing to the background TEQ. On the basis of statistical inference to the total population, it was estimated that about 36% of the properties in the floodplain and incinerator plume have at least one soil sample over the Michigan Department of Environmental Quality's soil direct contact criterion of 90 pg/g TEQ.     

Formation of PCDDs, PCDFs, and coplanar PCBs from polyvinyl chloride during combustion in an incinerator

Exhaust gases from the combustion of poly(vinyl chloride) (PVC), polyethylene (PE), polystyrene (PS), poly(ethylene terephthalate) (PET), and theirvarious mixtureswere analyzed for PCDDs, PCDFs, and coplanar PCBs by gas chromatography/mass spectrometry (GC/MS) in order to investigate the role of PVC in these chlorinated compounds. Total amounts of dioxins (PCDDs + PCDFs) found in the samples were 11.7 ng/g PE alone, 1.17 ng/g from PS alone, 25.3 ng/g from PET alone, 448 ng/g from PE with PVC, 140 ng/g from PS with PVC, 126 ng/g from PET with PVC, 824 ng/g from PVC alone under low-CO level, and 8,920 ng/g from PVC alone under high-CO level. CO level in high-CO level condition was 880 ppm which was 20 times greater than that in low-CO level condition. Formation of coplanar PCBs ranged from 0.095 ng/g (PE alone) to 77 ng/g (PVC alone under high-CO level). There is a clear correlation between dioxin formation and chloride content. PCDFs composed 80% (PET + PVC)--98% (PET alone) of the total dioxins formed in the exhaust gases. The results indicate that PVC contributes significantly to the formation of PCDDs, PCDFs, and coplanar PCBs from mixtures of plastics upon combustion.     

Formation of PCDDs,PCDFs, and coplanar PCBs from incineration of various woods in the presence of chlorides

Exhaust gases from the combustion of woods (Japanese red pine, Japanese cedar, Siebold's beech, seawater-impregnated Japanese red pine and Japanese cedar, waste woods containing chlordane, and waste woods containing pentachlorophenol) were collected at the outlet of a combustion chamber. A small-scale incinerator with a stationary grate was used. The samples were analyzed for PCDDs, PCDFs, and coplanar PCBs by gas chromatography/ mass spectrometry (GC/MS). When the grate temperature of the combustion chamber was lower than 700 degrees C, the total amount of PCDDs, PCDFs, and coplanar PCBs formed was proportional to the chlorine content of the combustion samples. On the other hand, when the grate temperature of the combustion chamber was higher than 800 degrees C, there was only a slight formation of PCDDs, PCDFs, and coplanar PCBs regardless of the chlorine content of the combustion samples. When the grate temperature was low, nearly 90% of total PCDDs, PCDFs, and coplanar PCBs formed were PCDFs, whereas when the grate temperature was higher, 50-80% of total PCDDs, PCDFs, and coplanar PCBs formed was PCDFs. The total amount of PCDDs, PCDFs, and coplanar PCBs formed in a high-temperature condition was approximately 1/50 of that formed in a low-temperature condition. Coplanar PCBs tended to form less than PCDDs or PCDFs did. Mono-ortho-PCBs were formed several times more than nonortho-PCBs. PCDDs or PCDFs contributed significantly to the values of TEQ, while coplanar PCBs contributed only slightly.     

Furan in commercial baby foods from the Spanish market: estimation of daily intake and risk assessment

ABSTRACT

The occurrence of furan in commercial baby food samples from the Spanish market was evaluated using an automated headspace solid-phase microextraction method coupled to gas chromatography-mass spectrometry (HS-SPME-GC-MS). A total of 76 baby food samples including infant formula, baby cereals, fruit in cans and/or jars, vegetables, meat, and fish, were surveyed for furan content. The lowest concentration of this compound was found in infant formula (<0.02–0.33 ng ml^?1), and cereal-based food (0.15–2.1 ng g^?1) while baby food containing fish showed the highest concentrations (19–84 ng g^?1). Following recommendation of the European Food Safety Authority (EFSA), the effect on furan content was evaluated of consumer home preparation of foods, heating and handling. Furan concentrations were reduced by up to 35% when samples were heated in a dish using microwave oven and by up to 53% when a hot water bath was used. Finally, we estimated the furan intake from baby food consumption (0.002–1.18 µg kg^?1 body weight day^?1) and we calculated the margin of exposure (MOE) from samples as purchased and also after home preparation of the food. For infant formula and cereal baby foods, the MOEs (26,278–412,776) indicated no infant health concern or priority, while for meat and fish-based baby foods the values pointed to a potential public health risk, even considering the furan losses during preparation at home.     

婴幼儿粉末食品的生产

<正> 婴幼儿配方食品是一种像乳一样的食品,用以补充或替代母乳,其主要成分应与母乳所蕴含的营养成分相同。要生产出高质量的婴幼儿配方食品,合适的生产工艺是关键。本文将介绍婴幼儿粉末食品的生产流程(图一),并探讨在设计工艺时应考虑的因素。