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Berlin Brandenburg

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  • 1
    Language: English
    In: Chemosphere, 2001, Vol.45(4), pp.543-551
    Description: Spray drift and edge-of-field runoff are regarded as important routes of nonpoint-source pesticide input into aquatic surface waters, with current regulatory risk assessment in Europe focussing largely on spray drift. However, the two routes of entry had rarely been compared directly in the same catchment. To this end, the concentrations and loads of the current-use insecticides azinphos-methyl (AZP) and endosulfan (END) were monitored in the Lourens River, South Africa downstream of a 400-ha fruit orchard area during normal farming practice. Spray drift-related peak pesticide levels in the tributaries were in the range of 95th-percentiles of standard drift values according to regulatory risk assessment procedures. Resulting concentrations in Lourens River water samples (n = 3) at a discharge of 0.28 m super(3)/s were as high as 0.04 plus or minus 0.01 mu g/l AZP and 0.07 plus or minus 0.02 mu g/l END. Pesticide levels at the same site during runoff following 3 storm events varying in rainfall between 6.8 and 18.4 mm/d (discharge: 7.5-22.4 m super(3)/s) were considerably higher: by factors between 6 and 37 for AZP (0.26-1.5 mu g/l) and between 2 and 41 for END (0.13-2.9 mu g/l). Levels of pesticides associated with suspended particles were increased during runoff only up to 1247 mu g/kg AZP and 12082 mu g/kg END. A possible reason for the relative importance of runoff is that runoff largely integrates potential pesticide input over both time and space, because the prerequisites for the occurrence of runoff in terms of application and plot characteristics as well as meteorological conditions are far less specific than for spray drift. A probability analysis based on pesticide application patterns and 10-yr rainfall data indicates that the frequencies of rainfall events greater than or equal to 10 and greater than or equal to 15 mm/d are 3.4 and 1.7 per spraying season, respectively.
    Keywords: Catchment ; Exposure Assessment ; Insecticides ; Nonpoint-Source Pollution ; Orchards ; Runoff ; Spray Drift ; Chemistry ; Ecology
    ISSN: 0045-6535
    E-ISSN: 1879-1298
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  • 2
    Language: English
    In: Chemosphere, 2003, Vol.51(6), pp.509-513
    Description: A water-sampling device to monitor the quality of water periodically and temporarily flowing out of concrete tubes, sewers or channels is described. It inexpensively and easily enables a qualitative characterization of contamination via these point-source entry routes. The water sampler can be reverse engineered with different sizes and materials, once installed needs no maintenance, passively samples the first surge, and the emptying procedure is short. In an agricultural catchment area in Germany we monitored an emergency overflow of a sewage sewer, an outlet of a rainwater sewer and two small drainage channels as input sources to a small stream. Seven inflow events were analysed for 20 pesticide agents (insecticides, fungicides and herbicides). All three entry routes were remarkably contaminated. We found parathion-ethyl concentrations of 0.3 mu g l super(-1), diuron up to 17.3 mu g l super(-1), ethofumesate up to 51.1 mu g l super(-1), metamitron up to 92 mu g l super(-1) and prosulfocarb up to 130 mu g l super(-1).
    Keywords: Herbicides ; Fungicides ; Insecticides ; Small Streams ; Point Sources ; Sewage Plant ; Rainwater Sewer ; Pipes ; Chemistry ; Ecology
    ISSN: 0045-6535
    E-ISSN: 1879-1298
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  • 3
    Language: English
    In: Chemosphere, 1996, Vol.32(10), pp.1963-1969
    Description: The suspended particle sampler (SPS) for monitoring pesticide concentrations in small streams is described. The sampler was evaluated in a small headwater stream in northern Germany which was contaminated with the insecticide fenvalerate during rainfall in June 1994. The amount retained by the SPS decreased with increasing flow rate. The results obtained with the SPS were compared with those obtained using a runoff-triggered sampler and with those obtained by analysis of bottom sediment. Concentrations obtained using the SPS, runoff-triggered sampler and analysis of bottom sediment were 71, 302 and 10.9 ug fenvalerate per kg. Suspended particles were more heavily contaminated than the stream bed. Temporal dynamics of contamination of suspended particles with fenvalerate and parathion were studied.
    Keywords: Chemistry ; Ecology
    ISSN: 0045-6535
    E-ISSN: 1879-1298
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  • 4
    Language: English
    In: Chemosphere, 2007, Vol.68(4), pp.605-612
    Description: Spraydrift and edge-of-field runoff are important routes of pesticide entry into streams. Pesticide contamination originating from spraydrift usually resides in the water phase, while pesticides in contaminated runoff are to a large extent associated with suspended particles (SPs). The effects of two organophosphorous insecticides (OPs), chloropyrifos (CPF) and azinphos-methyl (AZP), on acetylcholinesterase (AChE) activity in rainbow trout were compared between two exposure scenarios, simulating spraydrift- and runoff-borne contamination events in the Lourens River (LR), Western Cape, South Africa. NOECs of brain AChE inhibition, determined after 1 h of exposure followed by 24 h of recovery, were 0.33 μg l for aqueous CPF, 200 mg kg for SP-associated CPF and 20 mg kg for SP-associated AZP (at 0.5 g l SP). The highest aqueous AZP concentration tested (3.3 μg l ) was without significant effects. Previously reported peak levels of aqueous CPF in the LR (∼0.2 μg l ) are close to its NOEC (this study), suggesting a significant toxicological risk to fish in the LR. By contrast, reported levels of SP-associated OPs in the LR are 20–200-fold lower than their NOECs (this study). In a comparative in situ study, trout were exposed for seven days at agricultural (LR2, LR3) and upstream reference (LR1) sites. No runoff occurred during the study. Brain AChE was significantly inhibited at LR3. However, OP levels at LR3 (CPF 0.01 μg l ; AZP 0.14 μg l ) were minor compared to concentrations having effects in the laboratory (see above). Additionally, muscle AChE activity was significantly higher in caged trout from LR1 than in animals maintained in laboratory tanks.
    Keywords: Biomonitoring ; Fish ; Biomarker ; Spraydrift ; Runoff ; Chemistry ; Ecology
    ISSN: 0045-6535
    E-ISSN: 1879-1298
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  • 5
    Language: English
    In: Chemosphere, 2005, Vol.58(5), pp.683-691
    Description: Short-term pollution events via runoff are typical of streams in agricultural areas. Existing runoff models that simulate pesticide loss from agricultural fields require extensive input of information. There is thus a need for a simple model that can predict runoff-related pesticide concentrations in many streams on a landscape level when only limited data are available. To validate such a model, the runoff-related pesticide load of 18 small lowland streams was predicted with an extended version of the model "simplified formula for indirect loadings caused by runoff" (available from the Organisation for Economic Cooperation and Development, OECD). The authors suggest that the model presented here is suitable for use in routine exposure assessment of pesticides on a landscape level, as all input data (soil, slope, precipitation, pesticide application) are readily available from public authorities or could be generated by simple regional flood hydrograph curves. The predicted concentrations were compared with measured concentrations obtained by runoff-triggered sampling. Fungicides, insecticides and herbicides were detected in 17 streams, with max. concentrations measuring up to 29.7 mu g/l for the fungicide azoxystrobin and 0.3 mu g/l for the insecticide parathion- ethyl. Herbicides were detected in 16 streams, with max. concentrations between 13.7 and 1.2 mu g/l. The linear regression between the predicted and measured concentrations (log-values) shows significant correlations for the following pesticides: azoxystrobin: r super(2)=0.43; p=0.03; epoxiconazole: r super(2)=0.71; p〈=0.01; tebuconazole: r super(2)=0.77; p〈=0.01. The present model successfully explains the pesticide concentrations associated with single entry events caused by runoff, especially at concentration levels above ([gt-or-equal, slanted]0.5 mu g/l).
    Keywords: Exposure Assessment ; Non-Point Source ; Gis-Model ; Agricultural Active Agents ; Validation ; Chemistry ; Ecology
    ISSN: 0045-6535
    E-ISSN: 1879-1298
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  • 6
    Language: English
    In: Environmental Toxicology and Chemistry, August 2004, Vol.23(8), pp.1984-1990
    Description: We investigated the acute (5 d) effects of particle‐associated azinphosmethyl (AZP) in multispecies microcosms and assessed the results in the context to data obtained from a parallel field study undertaken in the Lourens River, South Africa. A runoff simulation was carried out in stream microcosms containing the macroinvertebrate fauna of an uncontaminated Lourens River site exposed to particle‐associated AZP (control and 200, 1,000, 5,000, 20,000 μg/kg; three replicates each) for 1 h. Measured AZP concentrations in filtered microcosm water resulted in the following values: Not detectable (control) and 0.03, 0.2, 1.1, and 6.9 μg/L, respectively. The two highest treatments resulted in significantly (analysis of variance [ANOVA]) reduced total numbers of individuals, while the number of taxa was affected in the 20,000 μg/kg treatment only. A comparison with previous data suggests that observed effects partly resulted from particle‐associated AZP. Particularly affected were six out of 14 macroinvertebrate taxa such as mayfly and stonefly taxa. In parallel, the distribution of macroinvertebrates at a pesticide‐free and a contaminated stretch of the Lourens River was monitored five times during the spraying season in 2001 and 2002. Out of the 14 core taxa found in the microcosm study as well as in the field approach, 10 showed comparable reactions in the microcosm experiment and in their field distribution; they were either classified as affected or unaffected in both studies. Thus, we conclude that particle‐associated AZP has the potential to affect the invertebrate community structure of the Lourens River and that microcosm studies employing fieldrelevant exposure scenarios may be valuable for a local risk assessment of pesticide‐related community disruptions in the Lourens River.
    Keywords: Aquatic Macroinvertebrates ; Community Structure ; Microcosms ; Particle‐Associated Azinphosmethyl ; Runoff
    ISSN: 0730-7268
    E-ISSN: 1552-8618
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  • 7
    Language: English
    In: Chemosphere, 1998, Vol.36(15), pp.3071-3082
    Description: A field method is described, which allows the qualitative estimation of pesticide contamination in the edge-of-field runoff. The method employs cheap and easy-to-use runoff sampling bottles, which were installed in an agricultural stream catchment over a period of three growing seasons. During this time 18 runoff events were detected, in nine of which insecticide contamination was measured (maximum concentrations: lindane 0.7 mu g l super(-1) and 12.7 mu g kg super(-1), parathion 20 mu g l super(-1) and 728 mu g kg super(-1), fenvalerate 18.4 mu g l super(-1) and 924 mu g kg super(-1)). These insecticides were detected mainly as particle-bound chemicals. On about 80 % of the occasions the presence or absence of runoff measured in the field was in agreement with a simulation of runoff presence or absence using the runoff model KINEROS.
    Keywords: Chemistry ; Ecology
    ISSN: 0045-6535
    E-ISSN: 1879-1298
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  • 8
    Language: English
    In: Environmental Toxicology and Chemistry, September 1999, Vol.18(9), pp.1948-1955
    Description: The study aims to evaluate the impact of insecticides associated with rainfall‐induced surface runoff from arable land on macroinvertebrate populations. These effects of insecticides were distinguished from the hydraulic stress also associated with surface runoff. Transient increase in discharge and insecticide contamination (maximum 6 μg/L parathion‐ethyl in stream water, 302 μg/L fenvalerate in suspended particulates) was observed in a headwater stream subsequent to surface runoff from arable land. In the aquatic macroinvertebrate community, eight of the eleven abundant species disappeared, and the remaining three were reduced significantly in abundance following the insecticide‐contaminated runoff. Recovery within 6 months was observed for four species and recovery within 11 months for nine species. Two species remained at a low population density for over a year. The effects of insecticides were distinguished from other parameters, such as hydraulic stress associated with surface runoff, as well. The causal connection between insecticide contamination and biological response was established by eliminating increased hydraulic stress during surface runoff using in‐parallel bypass microcosms containing the dominant species and . The mortality of these species was similar to that of the same species in the stream. Additional microcosms, disconnected from the stream during runoff events, served as a control. Thus, the toxic potential of the runoff water is considered to be responsible for the observed effect on the macroinvertebrates. It is concluded that agricultural insecticide input may alter the dynamics of macroinvertebrate communities in streams.
    Keywords: Pesticides ; Headwater Stream ; Macroinvertebrates ; Recovery ; Microcosm
    ISSN: 0730-7268
    E-ISSN: 1552-8618
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  • 9
    Language: English
    In: Aquatic Toxicology, 1999, Vol.46(3), pp.155-176
    Description: Information about the effects of agriculturally derived insecticide input on the aquatic fauna in the field is sparse. Runoff-related insecticide input and the resulting toxicological effects on the aquatic fauna (abundance, drift, emergence) at three sampling sites at different distances (450-1150 m) from the input location of contaminated edge-of-field runoff (erosion rill) were investigated. By means of event-triggered sampling it was shown that the transient (about 1 h) insecticide contamination in the stream was very high (e.g. 6 mu g l super(-1) parathion-ethyl in water, 302 mu g kg super(-1) fenvalerate in suspended particulates). The rates of loss of applied substance calculated on the basis of the application rate, the concentrations measured in the stream, and discharge data for both insecticides were below 0.1%, the value usually reported in the literature. The measured insecticide contamination in the stream had a strong negative effect on the aquatic macroinvertebrate community. Eight of the 11 common species vanished from 19 May on for a period of 3-6 months, although their life cycles include much longer aquatic stages. The remaining three species were significantly (P〈0.001) reduced in their population density, although in their normal life cycle the population density would increase due to summer reproduction. These effects were observed for the entire longitudinal stream section investigated (up to 1150 m from the edge-of-field runoff location). In contrast, the increase of drift rate (mainly G. pulex) and of the mortality in the drift (mainly caddisfly species), declined with increasing distance from the runoff site. The comparison of runoff events with and without insecticide contamination substantiates the crucial importance of the insecticide contamination for the observed effects. There was no correlation between the hydraulic component (discharge), turbidity or nutrient content and the observed toxicological effects (decrease in number of species, increased drift; increased mortality in the drift) on the aquatic fauna. Considering all these facts, it can be concluded that agricultural insecticide input may play an important role in the dynamics of macroinvertebrate communities in agricultural streams.
    Keywords: Abundance ; Drift ; Emergence ; Fenvalerate ; Field Studies ; Hydraulics ; Insects ; Macroinvertebrates ; Parathion-Ethyl ; Pesticides ; Streams ; Stress ; Chemistry ; Ecology
    ISSN: 0166-445X
    E-ISSN: 1879-1514
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  • 10
    Language: English
    In: Water SA, Jan 2001, Vol.27(1), pp.65-70
    Description: Pesticide contamination resulting from agricultural runoff depends on the time period between application and rainfall. In Western Cape orchard areas, the last pesticide application of the growing season in summer takes place at the end of February. Pesticides, total phosphates and total suspended solids (TSS) were measured in the Lourens River at the beginning of April 1999 prior to the first rainfall of the rainy season and in the middle of April during high discharge following the first rainfall of 9.6 mm/d. Pre-runoff samples indicated only contamination with total endosulfan (α, β, sulphate) at levels up to 0.06 µg/l. Runoff during the first rainfall event resulted in an increase in the levels of endosulfan, chlorpyrifos and azinphos-methyl, to 0.16, 〈 0.01 and 0.38 µg/l, respectively, in water samples and 245, 344, and 244 µg/kg in suspended sediments. In terms of chemical load the single rainfall event caused a loss of 15.1 g/h endosulfan, 1.8 g/h chlorpyrifos and 20.5 g/h azinphos-methyl. The second rainfall event caused no measurable increase in pesticide levels, although the amount of rain was even higher (14.4 mm/d). Levels of both total phosphate and TSS were also increased during the first runoff event. Transient contamination levels exceeded the target water quality range proposed by the South African Department of Water Affairs and Forestry (DWAF). The Lourens River site downstream of the farming area is identified as a site where potentially toxic conditions might arise.
    Keywords: Resuspended Sediments ; Phosphates ; River Water ; Rainfall ; Pesticides ; Suspended Particulate Matter ; Seasonal Variations ; Water Analysis ; Agricultural Runoff ; Water Pollution ; Rivers ; Phosphates ; Insecticides ; Rainfall ; Pesticides ; Agricultural Runoff ; Freshwater Pollution ; Endosulfan ; Suspended-Solids ; Agricultural Chemicals ; Phosphates ; Precipitation (Atmospheric) ; Pesticides (See Also Bactericides, Weedkillers) ; Seasons ; Runoff (Agricultural) (See Also Return Flows) ; Water Analysis ; Pollution (Water) ; Pollutant Identification ; Seasonal Variations ; Agricultural Runoff ; Phosphates ; Agricultural Chemicals ; Water Analysis ; Water Pollution Sources ; Rainfall ; Suspended Solids ; Pesticides ; South Africa, Western Cape, Lourens R. ; South Africa, Lourens R. ; Azinphosmethyl ; Chlorpyrifos ; Sources and Fate of Pollution ; Water Quality ; Freshwater Pollution ; Mechanical and Natural Changes ; Composition of Water ; South Africa, Lourens R. ; Azinphosmethyl ; Chlorpyrifos;
    ISSN: 03784738
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