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1.
Phthalate and PAH concentrations in dust collected from Danish homes and daycare centers 总被引:1,自引:0,他引:1
Sarka Langer Charles J. Weschler Andreas Fischer Gabriel Bekö Jørn Toftum Geo Clausen 《Atmospheric environment (Oxford, England : 1994)》2010,44(19):2294-2301
As part of the Danish Indoor Environment and Children’s Health (IECH) study, dust samples were collected from 500 bedrooms and 151 daycare centers of children (ages 3 to 5) living on the island of Fyn. The present paper reports results from the analyses of these samples for five phthalate esters (diethyl phthalate (DEP), di(n-butyl) phthalate (DnBP), di(isobutyl) phthalate (DiBP), butyl benzyl phthalate (BBzP), di(2-ethylhexyl) phthalate (DEHP)) and three PAHs (pyrene, benz[a]anthracene (B[a]A) and benzo[a]pyrene (B[a]P)). The three PAHs and DEHP were detected in dust samples from all sites, while DEP, DnBP, DiBP and BBzP were detected in more than 75% of the bedrooms and more than 90% of the daycare centers. The dust mass-fractions of both phthalates and PAHs were log-normally distributed. With the exception of DEP, the mass-fractions of phthalates in dust were higher in daycare centers than homes; PAH mass-fractions in dust were similar in the two locations. There was no correlation among the different phthalates in either homes or daycare centers. In contrast, the PAH were correlated with one another – more strongly so in homes (R2 = 0.80–0.90) than in daycare centers (R2 = 0.28–0.45). The dust levels of several phthalates (BBzP, DnBP and DEHP) were substantially lower than those measured in a comparable study conducted 6–7 years earlier in Sweden. Although usage patterns in Denmark differ from those in Sweden, the current results may also reflect a change in the plasticizers that are used in common products including toys. PAH levels were roughly an order of magnitude lower than those measured in Berlin and Cape Cod residences, suggesting that the Danish sites are less impacted by motor vehicle emissions. 相似文献
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Daphnia magna, a freshwater microcrustacean, is currently tested as an alternative experimental species in research dealing with nerve agents poisonings treatment. Because of this, the toxicity of the nerve agent tabun (a cyanide-group containing organophosphate) to Daphnia had to be examined by estimating the EC50 values. The immobilization of daphnids was chosen as the end-point. It was found that D. magna is sensitive to small amounts of tabun, even after 15 min exposure, and tabun toxicity increases with time. The estimated EC50 values for 15, 30, 45, and 60 min exposure were as follows: 67.39, 38.10, 26.95, and 21.9 μg l-1. In addition, the toxicity of media to which tabun was added 24 h before the start of experiments was examined. The results obtained indicate that daphnids can be used in experiments with nerve-agent intoxication treatment. 相似文献
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This paper presents a new tool for promoting business sustainability — indicators of sustainable production. It first introduces the concept of sustainable production as defined by the Lowell Center for Sustainable Production, University of Massachusetts Lowell. Indicators of sustainable production are discussed next, including their dimensions and desirable qualities. Based on the Lowell Center Indicator Framework, the authors suggest a new methodology of core and supplemental indicators for raising companies' awareness and measuring their progress toward sustainable production systems. Twenty-two core indicators are proposed and a detailed guidance for their application is included. An eight-step model provides a context for indicator implementation. The paper concludes with a summary of the strengths and weaknesses of the methodology as well as recommendations for testing the indicators. 相似文献
4.
Vesela I. Chalova Jihyuk Kim Paul H. Patterson Steven C. Ricke 《Journal of environmental science and health. Part. B》2016,51(4):230-235
Organic poultry is an alternative to conventional poultry which is rapidly developing as a response to customers' demand for better food and a cleaner environment. Although organic poultry manure can partially be utilized by organic horticultural producers, litter accumulation as well as excessive nitrogen still remains a challenge to maintain environment pureness, animal, and human health. Compared to conventional poultry, diet formulation without nitrogen overloading in organic poultry is even more complicated due to specific standards and regulations which limit the application of some supplements and imposes specific criteria to the ingredients in use. This is especially valid for methionine provision which supplementation as a crystalline form is only temporarily allowed. This review is focused on the utilization of various protein sources in the preparation of a diet composed of 100% organic ingredients which meet the avian physiology need for methionine, while avoiding protein overload. The potential to use unconventional protein sources such as invertebrates and microbial proteins to achieve optimal amino acid provision is also discussed. 相似文献
5.
Toxicity of the nerve agent tabun to Daphnia magna,a new experimental species in military toxicology
Daphnia magna, a freshwater microcrustacean, is currently tested as an alternative experimental species in research dealing with nerve agents poisonings treatment. Because of this, the toxicity of the nerve agent tabun (a cyanide-group containing organophosphate) to Daphnia had to be examined by estimating the EC50 values. The immobilization of daphnids was chosen as the end-point. It was found that D. magna is sensitive to small amounts of tabun, even after 15 min exposure, and tabun toxicity increases with time. The estimated EC50 values for 15, 30, 45, and 60 min exposure were as follows: 67.39, 38.10, 26.95, and 21.9 μg l?1. In addition, the toxicity of media to which tabun was added 24 h before the start of experiments was examined. The results obtained indicate that daphnids can be used in experiments with nerve-agent intoxication treatment. 相似文献
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Irene B. Zabala Díaz Vesela I. Chalova Corliss A. O'Bryan Philip G. Crandall Steven C. Ricke 《Journal of environmental science and health. Part. B》2013,48(2):162-166
The presence of Maillard reaction products (MRP) in foods and food components is due to the non-enzymatic reaction between protein and carbohydrate residues triggered by thermal steps during food processing. The objective of this study was to assess the effect of MRPs and increasing lysine concentrations on S. Typhimurium growth and the expression of cadA which may be an indirect determinant of Salmonella virulence response. Variations in lysine concentrations (from 0 to 0.5 mM) did not exert any effect either on the final optical density after 6-hour incubation or the growth rates of S. Typhimurium in media containing MRPs. In contrast to the reduced final absorbancy of the bacterial cultures grown with histidine and arginine MRPs supplementations (0.1%), growth rates, in general, remained unaltered by all MRPs at each lysine concentration when compared to the control (M9 pH 5.8, no MRPs added). The induction levels of cadA in media containing 0.1% MRPs were close to cadA induction in the reference media (M9, pH 5.8 and no MRPs) and did not exceed the corresponding values by more than approximately 30%. Although the observed negligible induction of cadA under these conditions complies with the concept of its potential “anti-virulence” function, additional studies involving various concentrations and more refined MRPs are needed. 相似文献
9.
Olofsson M Ek-Olausson B Ljungström E Langer S 《Journal of environmental monitoring : JEM》2003,5(6):963-970
Fluxes of some Volatile Organic Compounds (VOC) from grass were measured at a golf course in western Sweden, using the Relaxed Eddy Accumulation (REA) technique. The sampling was done by collecting VOC onto adsorbent tubes and the analysis was performed by thermal desorption followed by GC/MS. High emissions were observed after cutting. Transient fluxes of (Z)-3-hexenyl acetate (0.51 microg m(-2) s(-1)), (Z)-3-hexen-1-ol (0.14 microg m(-2) s(-1)) and (Z)-3-hexenal (0.40 microg m(-2) s(-1)) were measured, even at low temperatures. The REA technique requires a relatively large fetch area that is sometimes not available. Therefore, a procedure for correcting measured fluxes from a limited fetch is suggested. 相似文献
10.
While regulations have advanced product take-back in some markets, challenges to increasing product reuse and remanufacturing remain. Most research to date has focused on original equipment manufacturers taking back and remanufacturing their products, which is often problematic. The present study demonstrates that there are emerging opportunities for small companies with innovative business models to enter the market and advance product end-of-life (EoL) management. The paper examines the biotechnology industry – a growing sector with high spending on lab equipment and relatively short lifespans of research and development instruments. Building on previous research and analysis of industry practices and emerging drivers for product reuse and remanufacturing, the authors propose a framework for sustainable EoL management that includes five managerial drivers: financial benefits, space, ease/convenience, information, and sustainability goals. The paper concludes with discussion of the lessons learned and practical implications for managers in charge of purchasing or disposing of surplus equipment. 相似文献