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P. C. Oloffs L. J. Albright S. Y. Szeto 《Journal of environmental science and health. Part. B》2013,48(1):47-58
Abstract A fresh‐water lake, free from detectable pesticide residues before this study, was treated with a commercial formulation of technical chlordane. Water and sediment samples were analysed for chlordane residues 7, 24, 52, 279. and 421 days after treatment. Residues moved rapidly from the water to the lake bottom, supporting earlier results of a laboratory study with other organochlorines. In water, α‐ and γ‐chlordane concentrations remained proportional to total chlordane concentrations, as determined by total‐peak area measurements of gas‐liquid chronatogrammes. But in bottom sediments, α‐ and γ‐chlordane were more persistent than other constituents of technical chlordane, supporting recent evidence that quantification of technical chlordane residues on the basis of γ‐chlordane quantification only (or that of a‐ and γ‐chlordane only), can lead to incorrect results and that this method, although simple and fast, should no longer be recommended. 相似文献
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Sven Kullander 《Ambio》2010,39(3):249-256
Humankind is currently faced with the huge challenge of securing a sustainable energy supply and biofuels constitute one of
the major options. However, the commercially traded edible crops are barely sufficient to meet food demand of the present
world population. Certain regions, for example EU-27, do not even have a sufficient indigenous crop production. Of this follows
that motor biofuels based on edible crops should be avoided. To replace more than some percent of the fossil motor fuels,
non-edible biomass—rest products and wastes—should instead be considered for conversion to biofuels. In this way, about 10%
of the current fossil fuels can be replaced. Feeding a world population expected to grow by some 50% during the next 50 years
will be a major challenge. For environmental reasons it seems that agricultural land cannot be expanded very much, maybe not
at all. The solution to the increasing food demand seems therefore to be using the present crop production more efficiently
and increasing output from present agricultural land, maintaining biodiversity and climate stability within reasonable limits.
In the future, agriculture will need more energy and more water irrigation. Food production is, however, already very energy
demanding, requiring several times more externally provided energy than the energy content of the food itself. A sufficient
energy supply will be a key issue for the future farming! 相似文献
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The coasts of the Gulf of Mexico are zones exposed to the exploration and exploitation of petroleum sources, and the products generated in agricultural zones may become contaminated by persistent organic pollutants (POPs). The objective of the present study was to evaluate the presence of polychlorinated biphenyl compounds (PCBs) in milk from dairy production units near sources of environmental pollutants. It was confirmed that the seven congeners of nondioxin-like PCBs (NDL-PCBs) are present in milk where compounds PCB101, PCB118, PCB153 and PCB180 appear in 100% of the samples analyzed, the rank of concentration for the sum of the seven congeners fluctuating between 2.6 and 26 ng g−1 with a median of 6 ng g−1. None of the samples surpassed the provisional value established by the EU of 40 ng g−1 of milk fat for the sum of the seven congeners, indicator that was not affected by the season of the year (p < 0.05), whose median of 8.6 ng g−1 and 6.3 ng g−1 for rain and drought respectively. The concentrations of NDL-PCBs found in milk do not represent a problem for human health; however, they alert the existence of spontaneously generated, uncontrolled sources that may represent a potential danger for human and animal health. 相似文献
35.
KOMAL VIG D. K. SINGH H. C. AGARWAL 《Journal of environmental science and health. Part. B》2013,48(4):377-383
Dissipation and leaching behavior of 14C-monocrotophos was studied for 365 days under field conditions using PVC cylinders. The first set (24 cylinders) was spiked with 1.0 μCi 14C-labeled monocrotophos along with 1.06 mg unlabeled monocrotophos to give a concentration of 2 mg kg ?1 in the soil up to 15 cm depth. The second set (24 cylinders) received 14C-labeled monocrotophos along with other non-labeled insecticides viz., dimethoate @ 300 g a.i ha?1, deltamethrin @ 12.5 g a.i ha?1, endosulfan @ 750 g a.i ha?1, cypermethrin @ 60 g a.i ha?1, and triazophos @ 600 g a.i ha?1 at an interval of 15 days each as recommended for the cotton crop. 14C-monocrotophos dissipated faster, up to 45% in first 90 days in columns treated with only monocrotophos compared to 25% in columns that received monocrotophos along with other insecticides. However, both the columns showed similar residues 180 days onward. After 180 days of treatment, 46% radiolabeled residues were observed, which reduced up to 39.6% after 365 days. Leaching of 14C-monocrotophos to 15–30 cm soil layer was observed in both the experimental setups. In the 15–30 cm soil layer of both soil columns, up to 0.19 mg 14C-monocrotophos kg?1d. wt. soil was detected after 270 days. 相似文献
36.
Valorization of winery waste vs. the costs of not recycling 总被引:1,自引:0,他引:1
Devesa-Rey R Vecino X Varela-Alende JL Barral MT Cruz JM Moldes AB 《Waste management (New York, N.Y.)》2011,31(11):2327-2335
Wine production generates huge amounts of waste. Before the 1990s, the most economical option for waste removal was the payment of a disposal fee usually being of around 3000 Euros. However, in recent years the disposal fee and fines for unauthorized discharges have increased considerably, often reaching 30,000–40,000 Euros, and a prison sentence is sometimes also imposed. Some environmental friendly technologies have been proposed for the valorization of winery waste products. Fermentation of grape marc, trimming vine shoot or vinification lees has been reported to produce lactic acid, biosurfactants, xylitol, ethanol and other compounds. Furthermore, grape marc and seeds are rich in phenolic compounds, which have antioxidants properties, and vinasse contains tartaric acid that can be extracted and commercialized. Companies must therefore invest in new technologies to decrease the impact of agro-industrial residues on the environment and to establish new processes that will provide additional sources of income. 相似文献
37.
KHALIL TALEBI 《Journal of environmental science and health. Part. B》2013,48(5):595-603
The objectives of this study were to determine the persistence of phosalone (S-6-chloro-2,3-dihydro-2-oxobenzoxazol-3-ylmethyl O, O-diethyl phosphorodithioate) and diazinon (O,O-diethyl O-2-isopropyl-6-methylpyrimidin-4-yl phosphorothioate) residues in fresh and baled alfalfa under field conditions. Plots of alfalfa were sprayed with each insecticide. Fresh alfalfa was sampled up to 20 days after treatment, and dried alfalfa was sampled up to 25 weeks after baling. Samples were analyzed for residues using high performance liquid chromatography (HPLC) equipped with a UV detector. The half-lives of diazinon and phosalone in fresh alfalfa were 1.8 and 3.3 days, respectively. In baled alfalfa the half-life of diazinon and phosalone were 2.8 and 16.7 weeks, respectively. No diazinon residues were detected in baled alfalfa, sampled after week 9, although the concentration of phosalone found at week 25 was 5.51 mg/kg. 相似文献
38.
Henry F. Enos 《Journal of environmental science and health. Part. B》2013,48(6):1059-1070
Abstract The importance of quality control procedures to the collection of pesticide residue data is discussed. The equipment requirements of an adequate, safe pesticide residue laboratory are presented. Equipment maintenance, personnel training, and preservation of samples is also reviewed. Appropriate objectives for an intra‐laboratory quality control program are outlined. 相似文献