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Analytical Measurement and Levelsof Dioxins and PCBs in Biological Samples
2008
Focant, Jean-François | Eppe, Gauthier | De Pauw, Edwin
Nitrogen flows associated with food production and consumption system of Shanghai
2021
Liao, Chengsong | Xia, Yuling | Wu, Dianming
The release of reactive nitrogen (Nᵣ) from food production and consumption constitute the primary source of nitrogen pollution. However, nitrogen flows and the driving factors of food chain of Shanghai, China have not been previously studied. Here, we used a substance flow analysis model to analyze the changes in Nᵣ inputs and outputs in agricultural production, livestock and poultry farming, and food consumption related to the Shanghai food chain between 2000 and 2018. The driving forces of Nᵣ inputs, Nᵣ use efficiency, and Nᵣ surpluses/deficits in the food production and consumption system were also investigated. The results indicated that the main sources of Nᵣ input in the food production and consumption system were nitrogen fertilizers, livestock and poultry feed from external sources, and plant-based foods, which accounted for 36.28–59.45% of Nᵣ input in agricultural production, 37.32–76.57% of Nᵣ input in livestock and poultry farming, and 35.38–59.37% of Nᵣ input in food consumption, respectively. The main forms of Nᵣ outputs were surplus nitrogen in the soil, excretal nitrogen from livestock and poultry animals, and excretal nitrogen from humans, which accounted for 38.2–48.89% of Nᵣ output in agricultural production, 36.78–55.18% of Nᵣ output in livestock and poultry farming, and 85.36% of Nᵣ output in food consumption, respectively. From 2000 to 2018, the Nᵣ inputs per unit area from agricultural production decreased at a rate of 20.42% before 2012, and then increased at a rate of 5.72%. Moreover, the Nᵣ use efficiency of agricultural production component of Shanghai was at a low level, only 18.43–27.6%. Cultivation area of crops was the main driving forces of the Nᵣ input to food production and consumption system. These results provide essential data for controlling nitrogen pollution caused by Shanghai food production and consumption, which can serve as a reference for administrative agencies in formulating policies.
Mostrar más [+] Menos [-]Concentrations and distribution of chlorinated paraffins in Belgian foods
2021
McGrath, Thomas J. | Limonier, Franck | Poma, Giulia | Bombeke, Jasper | Winand, Raf | Vanneste, Kevin | Andjelkovic, Mirjana | Van Hoeck, Els | Joly, Laure | Covaci, Adrian
This study reports on concentrations of short- and medium-chain chlorinated paraffins (SCCPs and MCCPs, respectively) in a wide range of food samples (n = 211) purchased in Belgium during 2020. Samples were analysed by gas chromatography-mass spectrometry (GC-MS) and quantified using chlorine content calibration. ∑SCCPs were present above LOQ in 25% of samples with an overall range of <LOQ to 58 ng/g wet weight (ww), while ∑MCCPs were identified in 66% of samples ranging from <LOQ to 250 ng/g ww. ∑MCCP concentrations were greater than those of ∑SCCPs in all 48 samples in which both groups were detected with an average ∑MCCP/∑SCCP ratio of 5.8 (ranging from 1.3 to 81). In general, the greatest CP concentrations were observed in foods classified as animal and vegetable fats and oils and sugar and confectionary for both SCCPs and MCCPs. Significant correlations between lipid content in food samples and CP levels illustrated the role of lipids in accumulating CPs within foodstuffs, while industrial processing, food packaging and environmental conditions are each likely to contribute to overall CP loads. Selected samples (n = 20) were further analysed by liquid chromatography-high resolution MS (LC-HRMS) to investigate homologue profiles and the occurrence of long-chain CPs (LCCPs). LCCPs were detected in 35% of the 20 subset samples while the HRMS results for SCCPs and MCCPs matched closely with those obtained by GC-MS. This study reveals the widespread occurrence of SCCPs and MCCPs in Belgian food and indicates that LCCPs may represent a substantial contribution to overall CP levels in foodstuffs.
Mostrar más [+] Menos [-]Pentachlorophenol from an old henhouse as a dioxin source in eggs and related human exposure
2016
Piskorska-Pliszczynska, Jadwiga | Strucinski, Pawel | Mikolajczyk, Szczepan | Maszewski, Sebastian | Rachubik, Jaroslaw | Pajurek, Marek
High levels of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were detected in free-range eggs, and these levels reached a concentration of 29.84 ± 7.45 pg of WHO-TEQ/g of fat. This value exceeded the EU maximum permitted level of 2.5 pg of WHO-TEQ/g of fat for PCDD/F congeners by twelve-fold. A chemical analysis (HRGC-HRMS) revealed elevated amounts of OCDD, OCDF, HxCDD, HpCDD and HpCDF. During the investigation, samples of feed, soil, wall scrapings, wooden ceiling of the henhouse and tissues from laying hens were examined for dioxin contents (30 samples altogether). The long and complicated investigation found that the source of dioxins in the poultry farm was pentachlorophenol-treated wood, which was used as structural components in the 40-year-old farm building adapted to a henhouse. The wooden building material contained PCDD/Fs at a concentration of 3922.60 ± 560.93 pg of WHO-TEQ/g and 11.0 ± 2.8 μg/kg of PCP. The potential risk associated with dioxin intake was characterized by comparing the theoretically calculated weekly and monthly intakes with the toxicological reference values (TRVs), namely the Tolerable Weekly Intake (TWI) and Provisional Tolerable Monthly Intake (PTMI) values of 14 pg of WHO-TEQ/kg of bw and 70 pg of WHO-TEQ/kg of bw, respectively. The intake of dioxins estimated for high egg consumers (approximately 5–6 eggs/week) exceeded the TWI and PTMI values, which may pose a risk of delayed adverse health effects. The estimated dose of PCDD/Fs and DL-PCBs for children consuming 5 eggs per week exceeded the TWI by as much as 450% because of their nearly 5-fold-lower body weight. Although the dioxin intake estimated for the average consumption of eggs in the general population did not exceed any of the TRVs applied (58.7% TWI and 51.1% PTMI), such a situation should be considered unacceptable from a public health perspective because eggs are not the only source of these contaminants.
Mostrar más [+] Menos [-]Hexabromocyclododecane (HBCD) in the Korean food basket and estimation of dietary exposure
2016
Barghi, Mandana | Shin, Eun-su | Son, Min-Hui | Choi, Sung-Deuk | Pyo, Heesoo | Chang, Yoon Seok
1,2,5,6,9,10-hexabromocyclododecane (HBCD) is a brominated flame retardant that is used worldwide in expanded and extruded polystyrene foam and simultaneously emitted to the environment. HBCD can easily accumulate in animals and humans and cause neurotoxicity, thyroid hormone disruption, and reproductive disorders. Therefore, it is essential to monitor the HBCD concentrations in foods and estimate the human exposure through the diet. In this study a total of 521 food samples from eight food categories were sampled and analyzed for their HBCD content. Based on consumption data, the average dietary intake of the general Korean population and specific subgroups was calculated. The highest levels of HBCD were found in fish and shellfish (0.47 ng g−1 ww), and this was attributed to natural exposure to the contaminated marine environments and the HBCD bioaccumulation. In addition, the use of expanded polystyrene buoys in aquaculture was also found to be a potential source of HBCD in bivalves. The high solubility of α-HBCD in water and the persistence of this diastereomer compared to β- and γ-HBCD in biological tissues, led to higher accumulation of α-HBCD in animal-based foods. In contrast, the diastereomeric selectivity and lower metabolic capacity in plants compared with animals led to the predominance of γ-HBCD in plant-based foods. The dietary intake of HBCD was estimated to be 0.82 ng kg−1 bw d−1 in the general population and 2.89 ng kg−1 bw d−1 in children up to 5 years of age. The high HBCD intake in children was found to be a result of their lower body weight and their high consumption of milk and homemade Korean baby foods that usually contain fish.
Mostrar más [+] Menos [-]Plant senescence: A mechanism for nutrient release in temperate agricultural wetlands
2007
Kröger, R. | Holland, M.M. | Moore, M.T. | Cooper, C.M.
The beneficial uptake of nutrients by wetland plants is countered to some extent by nutrient release back into the aquatic environment due to vegetative die-back. This current study examined whether Leersia oryzoides, a common wetland plant, exhibits luxury uptake of nutrients from simulated farm runoff. The study also tested whether with subsequent decomposition, these nutrients are released back into the water column. When exposed to elevated (>2 mg/L N and P) runoff, L. oryzoides assimilated significantly higher concentrations of nitrogen (p < 0.001) and phosphorus (p < 0.001) in above-ground biomass as compared to non-enriched treatments (<0.05 mg/L N and P). Subsequently, senescence of enriched above-ground biomass yielded significantly higher concentrations of phosphorus (2.19 ± 0.84 mg P/L). Using L. oryzoides as our model, this study demonstrates nitrogen and phosphorus sequestration during the growing season and release of phosphorus in the winter. Release of sequestered nutrients during plant senescence.
Mostrar más [+] Menos [-]Biosafety risk assessment of nanoparticles: Evidence from food case studies
2021
Deng, Jing | Ding, Quan Ming | Jia, Ming Xi | Li, Wen | Zuberi, Zavuga | Wang, Jian Hui | Ren, Jia Li | Fu, Da | Zeng, Xiao Xi | Luo, Jun Fei
Nanotechnology provides a wide range of benefits in the food industry in improving food tastes, textures, sensations, quality, shelf life, and food safety. Recently, potential adverse effects such as toxicity and safety concerns have been associated with the increasing use of engineered nanoparticles in food industry. Additionally, very limited information is known concerning the behavior, properties and effects of food nano-materials in the gastrointestinal tract. There is explores the current advances and provides insights of the potential risks of nanoparticles in the food industry. Specifically, characteristics of food nanoparticles and their absorption in the gastrointestinal tract, the effects of food nanoparticles against the gastrointestinal microflora, and the potential toxicity mechanisms in different organs and body systems are discussed. This review would provide references for further investigation of nano-materials toxicity effect in foods and their molecular mechanisms. It will help to develop safer foods and expand nano-materials applications in safe manner.
Mostrar más [+] Menos [-]Chronic health risk comparison between China and Denmark on dietary exposure to chlorpyrifos
2020
Sang, Chenhui | Sørensen, Peter Borgen | An, Wei | Andersen, Jens Hinge | Yang, Min
Chlorpyrifos is one of the most heavily used pesticides in domestic and agricultural insect prevention globally. Given the potential neurotoxicity of chlorpyrifos and its high detection rates in food and drinking water, health risks attributable to chlorpyrifos residue in Chinese drinking water and food in both China and Denmark were assessed in this study. Mixed left-censored handling models were used to deal with the non-detected values in chlorpyrifos concentrations. Results show that chronic exposure imputed to chlorpyrifos residue is much lower than the reference dose, and will thus not pose appreciable health risk to the consumer. Compared to the total exposure from chlorpyrifos in drinking water and food sources, chronic exposure from drinking water sources in China accounts for 0–4.4%. Health risk owing to chlorpyrifos in food within China is 6-7-fold higher than in Denmark, and this coincides with the fact that all application of chlorpyrifos is banned in Denmark, in contrast to China. However, the Danish consumers are still exposed from imported food items. The main health risk contributors in China are the food groups of Grains and grain-based products and Vegetable and vegetable products, while the main chronic health risk contributor in Denmark is the food group of imported fruit and fruit products.
Mostrar más [+] Menos [-]Phthalates contamination in China: Status, trends and human exposure-with an emphasis on oral intake
2018
Wang, Wei | Leung, Anna Oi Wah | Chu, Lam Hang | Wong, Ming Hung
Despite the extensive production and use of phthalates in Asian countries, especially China, limited information is available about the current situation of human exposure in this region, and thus identification of further research needs is warranted. This review summarized the current trends of phthalates related to industrial production and human exposure by conducting a comprehensive assessment of phthalates contaminations in air, indoor dust, personal care products (PCPs), foodstuff and internal exposure in China, with comparisons with other countries. The concentrations of phthalates in indoor dust and PCPs in China were moderate, while concentrations in foods and air were among the highest worldwide. Dietary intake of phthalates varied with location, with hotspots in the southern and eastern coastal regions of China which correlated with the extensive industrial production recorded in these regions. This review firstly revealed the significantly differentiated food-type contribution profiles for phthalates in China and in other countries, which were affected by dietary habits and food contamination. The internal exposure for the Chinese population was found to be moderate, however there is a paucity of data available. Knowledge gaps identified concerning phthalates in China include trends in phthalates exposure, sources (e.g. PCPs, pharmaceuticals and medical treatment), and internal exposure derived from biomonitoring, warranting phthalates a research priority.
Mostrar más [+] Menos [-]Exposure risk of young population to lead: A case study in Le'an River Basin in Jiangxi Province, China
2016
Yu, Yanxin | Li, Qi | Wang, Hui | Wang, Bin | Lu, Qun | Yan, Zhenghong | Ding, Aizhong
Blood lead (Pb) level of children has widely been attracting public concern in China, particularly in the sites near mining or industrial areas. However, the policies about how to efficiently reduce the Pb intake of children are still under discussion. We collected six food types based on the local dietary habits and soils from Dexing, Leping, and Poyang Counties situated along the Le'an River Basin from upstream to downstream, and their Pb contents were analyzed. A Monte Carlo model was used to simulate the dietary chronic daily intake of Pb (CDIPb) from various foods and ingested soil by hand-to-mouth activities and its non-carcinogenic risk to children indicated by hazard quotient (HQ). Only in the rural area of Dexing, its soil and vegetables both had higher Pb content than the national tolerance limits of China, resulting its the highest CDIPb among all the areas. The Pb contents of the six food types and soils in other sites were overall below the limits. Vegetables and rice accounted for from 63% (Leping, urban) to 85% (Dexing, rural) of the total CDIPb and ingested soil overall took up ∼6%. In the rural area, Dexing had the highest proportion (82.8%) of children with HQ > 1, followed by Leping (36.1%) and Poyang (27.7%). Different order was found in the urban areas, i.e. Dexing (46.7%) > Poyang (41.0%) > Leping (26.4%). Vegetables and rice were overall the two major contributors to the total CDI of Pb, which should be focused on to control the Pb intake by the local children, especially for those living in the rural area of Dexing County.
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