Environmental impact and human health risks of polychlorinated dibenzo-p-dioxins and dibenzofurans in the vicinity of a new hazardous waste incinerator: a case study

The purpose of this study was to assess the environmental impact of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in the vicinity of a new hazardous waste incinerator (HWI) 4 years after regular operation of the facility. A double approach was carried out. The PCDD/F congener profiles corresponding to environmental samples, soil and herbage, collected before the HWI (baseline) and 4 years after starting regular operations, as well as PCDD/F profiles of air emission samples, were compared. The potential health risks (carcinogenic and noncarcinogenic) due to PCDD/F exposure were assessed for adults and children living in the neighborhood of the facility. Human exposure to PCDD/Fs was mainly due to dietary food intake. Comparisons between the PCDD/F congener profiles corresponding to the baseline and current surveys, as well as data concerning the human health risk assessment, indicate that the HWI in question does not cause additional risks to the environment orto the population living in the vicinity of the facility.     

Impact of natural organic matter on monochloramine reduction by granular activated carbon: the role of porosity and electrostatic surface properties

Steady-state monochloramine reduction in fixed-bed reactors (FBRs) was quantified on five types of granular activated carbon (GAC) using two background waters-one natural source water (LAW) containing 2.5-3.5 mg/L organic carbon and one synthetic organic-free water (NW). While more monochloramine was reduced at steady-state using NW compared to LAW for each GAC and empty-bed contact time studied, the differences in removal varied considerably among the GACs tested. Physical characterization of the GACs suggested that the degree of interference caused by natural organic matter (NOM) increased with increasing GAC surface area contained within pores greater than 2 nm in width. Acid/base and electrostatic properties of the GACs were not found to be significant in terms of NOM uptake, which indicated that size exclusion effects of the GAC pores overwhelmed the impact of the GAC surface chemistry. Therefore, selection of GAC to limit the impact of NOM on monochloramine reduction in FBRs should be based on pore size distribution alone, with the impact of NOM decreasing with decreasing mesoporosity and macroporosity.     

Natural and anthropogenic ethanol sources in north america and potential atmospheric impacts of ethanol fuel use

We used an ensemble of aircraft measurements with the GEOS-Chem chemical transport model to constrain present-day North American ethanol sources, and gauge potential long-range impacts of increased ethanol fuel use. We find that current ethanol emissions are underestimated by 50% in Western North America, and overestimated by a factor of 2 in the east. Our best estimate for year-2005 North American ethanol emissions is 670 GgC/y, with 440 GgC/y from the continental U.S. We apply these optimized source estimates to investigate two scenarios for increased ethanol fuel use in the U.S.: one that assumes a complete transition from gasoline to E85 fuel, and one tied to the biofuel requirements of the U.S. Energy Indepence and Security Act (EISA). For both scenarios, increased ethanol emissions lead to higher atmospheric acetaldehyde concentrations (by up to 14% during winter for the All-E85 scenario and 2% for the EISA scenario) and an associated shift in reactive nitrogen partitioning reflected by an increase in the peroxyacetyl nitrate (PAN) to NO(y) ratio. The largest relative impacts occur during fall, winter, and spring because of large natural emissions of ethanol and other organic compounds during summer. Projected changes in atmospheric PAN reflect a balance between an increased supply of peroxyacetyl radicals from acetaldehyde oxidation, and the lower NO(x) emissions for E85 relative to gasoline vehicles. The net effect is a general PAN increase in fall through spring, and a weak decrease over the U.S. Southeast and the Atlantic Ocean during summer. Predicted NO(x) concentrations decrease in surface air over North America (by as much 5% in the All-E85 scenario). Downwind of North America this effect is counteracted by higher NO(x) export efficiency driven by increased PAN production and transport. From the point of view of NO(x) export from North America, the increased PAN formation associated with E85 fuel use thus acts to offset the associated lower NO(x) emissions.     

Physical and oxidative stability of pre-emulsified oil bodies extracted from soybeans

Soybeans contain oil bodies that are coated by a layer of oleosin proteins. In nature, this protein coating protects the oil bodies from environmental stresses and might be utilised by food manufacturers for the same purpose. In this study, an aqueous extraction method was developed to increase the yield of oil bodies extracted from soybean. This method involved a two-step procedure: (i) blending, dispersion, and filtration of soybeans; (ii) homogenisation, suspension, and centrifugation of the filter cake. Using this extraction method about 65% of the oil bodies could be obtained. The mean particle diameter (d₄₃) and sedimentation of the resulting oil bodies increased during storage, suggesting they were prone to aggregation. Heat treatment (90 °C, 30 min) of the oil body suspensions immediately after extraction improved their storage stability, which was attributed to deactivation of endogenous enzymes such as lipase and lipoxygenase. Heat treatment did not adversely affect the oxidative stability of the oil body suspensions at pH 3 or 7 during storage at 37 °C. These results suggest that this aqueous extraction method can be used to prepare oil body suspensions with improved long-term stability.     

Effects of calf diet, antioxidants, packaging type and storage time on beef steak storage

The effect of basal dietary supplemented with vegetable oils plus vitamin E (sunflower, soybean, linseed and a basal diet control), type of packaging (MAP or vacuum), addition of natural antioxidant (grape seed, rosemary) and storage time (0, 7, 14 and 21 days) on lipid oxidation, color stability, vitamin E content, and total aerobic bacterial counts in steaks of Longissimus thoracis was studied. The triple interaction diet × time × packaging affected oxidative stability, redness and yellowness of the meat. TBARS values did not increase with time in vacuum-packaged samples for all dietary treatments. However, samples from MAP and control showed the highest TBARS values after 21 days of storage (0.72 mg MDA/kg of meat, P < 0.05). Both exogenous antioxidant extracts and MAP maintained low total aerobic counts in steaks until the 21st day. Calves should be fed a diet supplemented with L-VE, stored in MAP and treated with grape seed extract to extend the shelf life of their meat.     

Electric vehicles in China: emissions and health impacts

E-bikes in China are the single largest adoption of alternative fuel vehicles in history, with more than 100 million e-bikes purchased in the past decade and vehicle ownership about 2× larger for e-bikes as for conventional cars; e-car sales, too, are rapidly growing. We compare emissions (CO(2), PM(2.5), NO(X), HC) and environmental health impacts (primary PM(2.5)) from the use of conventional vehicles (CVs) and electric vehicles (EVs) in 34 major cities in China. CO(2) emissions (g km(-1)) vary and are an order of magnitude greater for e-cars (135-274) and CVs (150-180) than for e-bikes (14-27). PM(2.5) emission factors generally are lower for CVs (gasoline or diesel) than comparable EVs. However, intake fraction is often greater for CVs than for EVs because combustion emissions are generally closer to population centers for CVs (tailpipe emissions) than for EVs (power plant emissions). For most cities, the net result is that primary PM(2.5) environmental health impacts per passenger-km are greater for e-cars than for gasoline cars (3.6× on average), lower than for diesel cars (2.5× on average), and equal to diesel buses. In contrast, e-bikes yield lower environmental health impacts per passenger-km than the three CVs investigated: gasoline cars (2×), diesel cars (10×), and diesel buses (5×). Our findings highlight the importance of considering exposures, and especially the proximity of emissions to people, when evaluating environmental health impacts for EVs.     

Physicochemical properties of lactoferrin stabilized oil-in-water emulsions: Effects of pH,salt and heating

Lactoferrin is a globular protein from bovine milk with an unusually high isoelectric point (pI > 8), which may lead to novel functional properties in foods and other products because it is cationic across a wide pH range. In this study, we investigated the influence of pH (2–9), NaCl addition (0–200 mM), CaCl₂ addition (0–200 mM), and thermal processing (30–90 °C, 20 min) on the stability of lactoferrin (LF) stabilized oil-in-water emulsions. At ambient temperature, the emulsions were stable to droplet aggregation at low pH (pH ≤ 6), but exhibited some aggregation at pH ≈ pI (pH 7–9). The thermal stability of the emulsions depended on pH, holding temperature, and thermal history. When LF-coated droplets were heated in distilled water, and then their pH was adjusted in the range 2–9, they were highly unstable to aggregation at pH 7 and 8. On the other hand, when the pH was altered in the range 2–9 first, and then they were heated, the LF-coated droplets were highly unstable to aggregation at pH ≥ 5 when heated above 50 °C. The stability of the emulsions to salt addition depended on pH and salt type, which was attributed to counter-ion binding and electrostatic screening effects. For NaCl, emulsions were stable from 0 to 200 mM at pH 3 and 9, but aggregated at ≥100 mM at pH 6. For CaCl₂, emulsions were stable from 0 to 200 mM at pH 3, but aggregated with ≥150 mM CaCl₂ at pH 6 and 9. These results have important implications for the formulation and production of emulsion-based products using lactoferrin as an emulsifier.     

Structured biopolymer-based delivery systems for encapsulation,protection, and release of lipophilic compounds

Food-grade biopolymers, such as proteins and polysaccharides, can be used to create a diverse range of delivery systems suitable for encapsulating, protecting, and delivering lipophilic functional components, such as ω-3 rich oils, conjugated linoleic acid (CLA), oil-soluble vitamins, flavors, colors, and nutraceuticals. This article provides an overview of a number of different approaches that can be used to create structured delivery systems based on biopolymers, including molecular complexation, coacervation, thermodynamic incompatibility, moulding, and extrusion methods. These delivery systems can be produced from food-grade ingredients using simple processing operations (e.g., mixing, homogenizing, and thermal processing). The structure, production, performance, and potential applications of each type of structured delivery system are discussed.     

Physical and mechanical properties of gypsum particleboard reinforced with Portland cement

High thickness swelling, high water absorption and low mechanical properties of gypsum particleboard limit its utilization in building construction. Gypsum particleboard reinforced with Portland cement could result in a product with higher mechanical properties and an acceptable resistance to moisture. Physical and mechanical properties of gypsum-cement particleboards were analyzed for specimens previously conditioned at 20?°C and 60% relative humidity and then soaked in water for 24 hours. The results showed that Portland cement incorporation increased the mechanical resistance of the boards. In the dry state, Portland cement addition generated a modulus of rupture increase ratio of 53% and an internal bond strength increase ratio of 206%. Higher increase ratios were obtained after 24 hours water soaking. An increase ratio of 642% was obtained for the modulus of rupture and 97% for hardness. Furthermore, the addition of Portland cement resulted in a reduction ratio of 21% for water absorption after 2 hours water soaking and 26% after 24 hours water soaking. Moreover, reduction ratios of 43% and 61% in thickness swelling and 33% and 46% in linear variation were observed after 2 and 24 hours water soaking. It can be concluded that Portland cement is a suitable reinforcing material for improving the performance of gypsum particleboard.