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Jan Bernd Barhorst Roland Kubiak 《Environmental science and pollution research international》2009,16(5):582-589
Background, aim and scope The use of sodium hypochlorite (HYP) in viticulture results in effluents which are contaminated with halogenated substances.
These disinfection by-products (DBPs) can be quantified as group parameter ‘adsorbable organic halogens’ (AOX) and have not
been determined in effluents of viticulture yet. The substances that are detected as AOX are unknown. The AOX can be composed
of harmless substances, but even toxic contaminants. Thus, it is impossible to assess ecological impacts. The aim of this
study is to determine the quantification of AOX and DBPs after the use of HYP. This will be helpful to reduce environmental
pollution by AOX.
Materials and methods The potential of HYP to generate AOX was determined in laboratory-scale experiments. Different model solutions were treated
with HYP according to disinfection processes in viticulture and conditions of AOX formation in effluents were simulated. AOX
were quantified using the flask-shaking method and identified DBPs were investigated by gas chromatography–mass spectrometry.
Results Treatment with HYP resulted in the formation of AOX. The percentage conversion of HYP to AOX was up to 11%. Most important
identified DBPs in viticulture are chloroform, dichloroacetic acid and trichloroacetaldehyde. In addition, the formation of
carbon tetrachloride (CT), 1,1,1-trichloropropanone, 2,4-dichlorobenzoic acid and 2-chloro-/2,4-dichlorophenylacetic acid
was investigated. It was demonstrated that reaction temperature, concentration of HYP and type of organic matter have important
influence on the formation of chlorinated DBPs.
Discussion The percentage conversion of HYP to AOX was similar to other published studies. Although a correlation of single compounds
and AOX is difficult, chloroform was the predominant AOX. Generation of the volatile chloroform should be avoided due to possible
adverse effects. The generation of dichloroacetic acid is of minor importance on account of biodegradation. Trichloroacetaldehyde
and 1,1,1-trichloropropanone are weak mutagens and their formation should be avoided.
Conclusions The generation of AOX and chlorinated DBPs can be minimised by reducing the concentrations of the organic materials in the
effluents. The removal of organic matter before disinfection results in a decreased formation of AOX. HYP is an effective
disinfectant; therefore, it should be used at low temperatures and concentrations to reduce the amount of AOX. If possible,
disinfection should be accomplished by the use of no chlorine-containing agents. By this means, negative influences of HYP
on the quality of wine can also be avoided.
Recommendations and perspectives Our results indicate that HYP has a high potential to form AOX in effluents of viticulture. The predominant by-products are
chloroform, dichloroacetic acid and trichloroacetaldehyde. In further research, wastewaters from a winery and the in- and
outflows of two sewage treatment plants were sampled during vintage and analysed. These results will be discussed in a following
paper. 相似文献
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This study aimed to investigate the persistence of imidacloprid in soil after application to cotton seeds and to obtain a complete picture on the mass balance of this compound in soil and cotton plants. The study was carried out as a pot culture experiment under laboratory conditions using a Gaucho formulation containing 14C-labeled imidacloprid. Three treatments of cotton seeds were made in sandy loamy soil: live seeds grown in autoclaved soil, dead seeds put in live soil and live seeds grown in live soil. Results showed that total 14C recoveries decreased by time ranging 93.8–96.2, 77.1–88.4 and 53.5–62.4% of the applied radioactivity at 7, 14, and 21 d after application, respectively. The reduction in the extracted 14C from soil coincided with the increase of non-extracted ones. Levels of bound 14C was always less in autoclaved soil than in live ones. Results revealed also that only 1.8–6.8% of the applied 14C was taken up by the plants and fluctuated within the test period. 14C levels were higher in plants grown in autoclaved soil than those in live ones and the radioactivity tended to accumulate on the edges of cotton leaves. Most of the radioactivity in the soil extracts was identified as unchanged 14C-imidacloprid. 相似文献
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The fate of 14C-labelled formulated parathion-methyl was investigated for 24 h after application to French beans in a laboratory chamber, where the air temperature and air humidity fluctuations as measured outdoors during a day in August 1993 could be simulated. The wind velocity directly above the plant stand and the radiation intensity could also be simulated with slight restrictions. Under these conditions, 65.9 % and 65.3 % of the A.I. applied volatilized and were directly determined in air samples in two experiments carried out under identical conditions. 28.9 % and 27.8% were determined after 24 h on the plants, only a part of this radioactivity still representing unchanged parathion methyl. The recovery of the radioactivity applied was 94.8 % and 93.1 %, respectively in the two experiments. 相似文献
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