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7. Guidance for summarizing and evaluating aquatic micro- and mesocosm studies : a guidance document of the Dutch Platform for the Assessment of Higher Tier Studies

Author

de Jong, F.M.W., Brock, T.C.M., Foekema, E.M., and Leeuwangh, P.

Subjects
surface water, methodology, experiments, pesticides, richtlijnen (guidelines), ecosystemen, Wageningen Marine Research, oppervlaktewater, registration, pesticiden, Alterra - Centre for Water and Climate, aquatische ecosystemen, Wageningen Environmental Research, guidelines, experimenten, ecosystems, registratie, methodologie, Alterra - Centrum Water en Klimaat, aquatic ecosystems
Abstract

A guidance document has been developed for ensuring that the test results required for the registration of pesticides be supplied in a uniform and transparent manner. This document is specifically directed at experiments carried out in artificial ecosystems in surface water (micro- and mesocosm studies)

Published
2008

10. Guidance for summarizing and evaluating aquatic micro- and mesocosm studies. A guidance document of the Dutch Platform for the Assessment of Higher Tier Studies

Author

SEC, de Jong FMW, Brock TCM, Foekema EM, Leeuwangh P, SEC, de Jong FMW, Brock TCM, Foekema EM, and Leeuwangh P

Abstract

RIVM rapport:Er is een richtsnoer ontwikkeld om testresultaten voor de toelatingsprocedure voor gewasbeschermingsmiddelen eenvormig en transparant aan te reiken. Het richtsnoer geldt specifiek voor experimenten in nagebootste ecosystemen in oppervlaktewater (zogenoemde micro- en mesocosm studies). Het richtsnoer is ontwikkeld door het Nederlandse Platform voor de Beoordeling van Higher Tier Studies, waarvan het RIVM het secretariaat voert. Bij de toelatingsprocedure voor gewasbeschermingsmiddelen leveren aanvragers (bijvoorbeeld de bestrijdingsmiddelenfabrikanten) informatie aan het College voor de toelating van gewasbeschermingsmiddelen en biociden (Ctgb). Aan de hand hiervan beoordeelt het Ctgb of een bepaald gebruik van een middel toelaatbaar is in Nederland. De geleverde informatie betreft onder andere complexe en vaak omvangrijke informatie over micro- en mesocosm studies. Het Ctgb laat deze studies vervolgens door verschillende externe partijen samenvatten en evalueren. Door verschillen in werkwijze kunnen de vorm van deze samenvattingen en evaluaties, en soms zelfs de conclusies, verschillen. Vandaar de wens van het Ctgb om de evaluaties en samenvattingen van ecosystemen in oppervlaktewater te standaardiseren. Een aanverwant doel is hiermee het beoordelingsproces transparanter maken., A guidance document has been developed for ensuring that the test results required for the registration of pesticides be supplied in a uniform and transparent manner. This document is specifically directed at experiments carried out in artificial ecosystems in surface water (micro- and mesocosm studies). It has been developed by the Dutch Platform for the Assessment of Higher Tier Studies (PHTS), of which the Netherlands National Institute of Public Health and the Environment (RIVM) is the secretariat. Within the framework of the rules and regulations governing pesticide registration in the Netherlands, applicants (e.g. manufacturers of crop protection agents) are required to supply all necessary information to the Dutch Board for the Authorisation of Crop Protection Products and Biocides (Ctgb). Based on this information the Ctgb assesses whether the use specified for a specific product is acceptable. Complex and often extensive data on micro- and mesocosm studies can be a necessary part of the information provided. The Ctgb, an independent administrative body, requests various external institutes to summarize and evaluate these studies. Potential differences in the evaluator's methodology may lead to a lack of uniformity in the form and content of the summaries and evaluations and - occasionally - in the conclusions. These differences were the primary motivating factor for Ctgb to harmonize the evaluation reports of studies on ecosystems of surface water bodies. A secondary aim was to increase the transparency of the registration process.

Published
2008

11. Effects of the insecticide Dursban 4E (active ingredient chlorpyrifos) in outdoor experimental ditches: I. comparison of short-term toxicity between the laboratory and the field

Author

Wijngaarden, R. P. A., Paul van den brink, Crum, S. J. H., Oude Voshaar, J. H., Brock, T. C. M., and Leeuwangh, P.

Subjects
experimenteel veldonderzoek, plant protection, gewasbescherming, pesticide residues, Winand Staring Centre for Integrated Land, Soil and Water Research, chemicals, field experimentation, persistentie, toxicologie, persistence, pesticides, pesticidenresiduen, Staring Centrum, chemicaliën, pesticiden, toxicology
Abstract

By means of the insecticide chlorpyrifos, results of acute single-species toxicity tests were compared with direct effects in outdoor mesocosms. In the mesocosms, chlorpyrifos concentrations between 0.1 and 44 Šg/l were sprayed once. Acute effects were observed on arthropods. Effects could be quantified for seven species. For these species, EC50s were similar to their laboratory EC50s. The most sensitive standard test species was about representative of susceptible indigenous species. Effects were negligible at 0.1 Šg/l. A factor of 0.1 * 48-h LC50 of Daphnia magna may have protected most species in the community from direct effects. A safety factor of 0.01 may have protected the most susceptible taxa we found.

Published
1996

12. Beleidsadvisering over bestrijdingsmiddelen en nutriënten

Author

Leeuwangh, P. and Noij, I.G.A.M.

Subjects
Staring Centrum, Winand Staring Centre for Integrated Land, Soil and Water Research, Life Science
Abstract

Bij advisering over te voeren milieu- of natuurbeleid moet disciplinaire kennis uit verschillende vakgebieden worden geontegreerd. Dit artikel geeft hiervan drie voorbeelden: de risicobeoordeling van bestrijdingsmiddelen voor het milieu; de Milieubalans, waarin de huidige milieukwaliteit wordt beschreven; en de Milieuverkenning, waarin vooraf de gevolgen van mogelijk nieuw beleid worden doorgerekend. De adviezen zijn ogenschijnlijk duidelijk. De gekozen uitgangspunten en onzekerheden in de rekenmodellen kunnen het advies echter vergaand beonvloeden.

Published
1996

13. Effects of the insecticide Dursban 4E (active ingredient chlorpyrifos) in outdoor experimental ditches: II. invertebrate community responses and recovery

Author

Paul van den brink, Wijngaarden, R. P. A., Lucassen, W. G. H., Brock, T. C. M., and Leeuwangh, P.

Subjects
experimenteel veldonderzoek, plant protection, gewasbescherming, pesticide residues, Winand Staring Centre for Integrated Land, Soil and Water Research, chemicals, field experimentation, persistentie, toxicologie, persistence, pesticides, pesticidenresiduen, Staring Centrum, chemicaliën, pesticiden, toxicology
Abstract

This paper describes long-term effects of chlorpyrifos on macro-invertebrates and zooplankton after a single application. Crustaceans and insects showed a rapid, concentration-dependent decrease in numbers after application (direct effects). A significant increase in gastropods and oligochaetes was found, suggesting indirect effects. The start of recovery of the invertebrate populations affected depended not only on the susceptibility of the taxa, but also on ecological characteristics, such as length of the life cycle. Safe concentrations, based on no observed short-term effect levels for some characteristic indigenous taxa susceptible to chlorpyrifos, also appeared to protect the total invertebrate community in the long term.

Published
1996

14. Future applications of TOXSWA

Author

Leeuwangh, P.

Subjects
Staring Centrum, Winand Staring Centre for Integrated Land, Soil and Water Research, Life Science
Abstract

A tiered strategy is proposed for the use of TOXSWA in the registration procedure. For a quick scan of the potential environmental risk it is suggested that TOXSWA should be used in a standard setting of environmental conditions. Several standard settings, reflecting different Dutch situations, under which TOXSWA will be used will be identified. To enable a quick scan, it is intented to present TOXSWA in the form of tables. In case a more refined risk assessment is needed, the specific conditions have to be identified and implemented in the model. It is recommended that TOXSWA should be validated under various environmental conditions before it is used the model in the registration of pesticides.

Published
1995

15. Modellering van emissieroutes naar en lotgevallen van bestrijdingsmiddelen in kleine waterlopen

Author

Groenendijk, P. and Leeuwangh, P.

Subjects
plant protection, gewasbescherming, pesticide residues, Winand Staring Centre for Integrated Land, Soil and Water Research, persistentie, pesticidenresiduen, water quality, soil, models, oppervlaktewater, waterlopen, Staring Centrum, pesticiden, uitspoelen, modellen, water pollution, research, surface water, persistence, pesticides, waterkwaliteit, streams, onderzoek, rivers, leaching, bodem, rivieren, waterverontreiniging
Abstract

De emissieroutes snelle drainage en uitspoeling via de bodem van bestrijdingsmiddelen naar het oppervlaktewater zijn gekwantificeerd. Concentraties in deze afvoeren lopen op tot enkele milligrammen per liter. Andere emissieroutes zijn overwaaiing en oppervlakkige afspoeling. Het simulatiemodel TOXSWA berekent realistische blootstellingsconcentraties in watergangen. Het berekent de verdeling van bestrijdingsmiddelen in waterkolom en waterbodem van een sloot en bevat alle relevante processen die de lotgevallen ervan in het oppervlaktewater beonvloeden. Sorptie aan waterplanten is een belangrijk maar onbekend proces. De nieuwe methodiek maakt een gebiedsgerichte normstelling voor effecten op waterorganismen mogelijk.

Published
1995

16. Voortgangsbewaking emissiedoelstellingen in het meerjarenplan gewasbescherming

Author

Leeuwangh, P., Boesten, J.J.T.I., Leistra, M., and Merkelbach, R.C.M.

Subjects
Staring Centrum, Winand Staring Centre for Integrated Land, Soil and Water Research, Life Science
Abstract

Om de taakstellingen voor emissiereductie te evalueren moeten meetinstrumenten worden ontwikkeld. Instrumenten om de emissiereductie voor grond- en oppervlaktewater te evalueren kunnen snel toepasbaar worden gemaakt. Een instrument voor lucht vraagt meer tijd maar is zeer belangrijk, aangezien meer dan 20% van de gebruikshoeveelheid bestrijdingsmiddelen de lucht ingaat. Doordat er niet genoeg gegevens uit de referentieperiode 1984-1988 zijn, is er slechts een indicatie van de mate waarin taakstellingen voor 1995 zijn gehaald. Sinds 1992 worden de gegevens beter vastgelegd, zodat de evaluatie-instrumenten een betrouwbare kwantitatieve evaluatie kunnen geven voor het ijkjaar 2000 ten opzichte van de periode vanaf 1992.

Published
1995

18. Fate and effects of the insecticide Dursban 4E in indoor Elodea-dominated and macrophyte-free model ecosystems: 1. Fate and primary effects of the active ingredient chloropyrifos

Author

Brock, T.C.M., Crum, S.J.H., van Wijngaarden, R., Budde, B.J., Tijink, J., Zuppelli, A., and Leeuwangh, P.

Subjects
plant protection, chloride, gewasbescherming, milieu, fenolen, organophosphorus compounds, phenols, Toxicology, dioxinen, derivaten, dioxins, pesticiden, Nature Conservation Department, phenol, pollution, nontarget effects, pentachlorophenol, Toxicologie, verontreinigende stoffen, pentachloorfenol, toxiciteit, selectivity, toxicity, pesticides, Afdeling Natuurbehoud en Natuurbeheer, nadelige gevolgen, pollutants, adverse effects, derivatives, fenol, organo-fosforverbindingen, verontreiniging, nontarget organisms, environment, onbedoelde effecten, selectiviteit, niet-doelorganismen
Published
1992

22. Acute toxicity of chlorpyrifos to fish, a newt, and aquatic invertebrates.

Author

Wijngaarden, R., Leeuwangh, P., Lucassen, W., Romijn, K., Ronday, R., Velde, R., and Willigenburg, W.

Subjects
ACUTE toxicity testing, CHLORPYRIFOS, ORGANOPHOSPHORUS insecticides, FISHES, LISSOTRITON vulgaris, AQUATIC invertebrates, ACETONE, DISTILLED water
Abstract

The article presents a study regarding the acute toxicity of chlorpyrifos to fish, a newt Triturus vulgaris, and aquatic invertebrates. The study performed all tests on the organo-phosphorus insecticide chlorpyrifos and stock solutions were made by diluting chlorpyrifos in acetone or Dursban® 4E in distilled water. The study has found that the Dursban® 4E Blank has no observable effects on the tested species.

Published
1993
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23. Ordination techniques for analysing response of biological communities to toxic stress in experimental ecosystems

Author

Wijngaarden, René P. A., Brink, Paul J., Oude Voshaar, Jan H., and Leeuwangh, Peter

Abstract

The ordination techniques principal component analysis (PCA) and redundancy analysis (RDA) are considered to be useful tools for evaluating community responses in experimental ecotoxicology. Concepts and interpretation of these techniques are summarized. Application of PCA and RDA is illustrated in a case study. In this study, the effects of a single application of the insecticide Dursban® 4E (a.i. chlorpyrifos) on an aquatic macroinvertebrate community in microcosms were analysed. Four treatment (nominal chlorpyrifos concentration: 35 µg l-1) and four control microcosms were used. PCA visualized a change in species composition with time. Immediately after treatment, a major shift in species composition occurred in treated microcosms. RDA demonstrated that this shift was due to the treatment. RDA also showed that non-arthropods were generally insusceptible to chlorpyrifos; most arthropods were affected. Dynamics of separate taxa were visualized, giving indications of possible primary and secondary effects for these taxa. A Monte Carlo permutation test was used to decide whether treatment had a significant effect on the species composition and to investigate the state of recovery in time. In general, the RDA results gave an adequate condensation of detailed information on abundance and effects obtained by more conventional univariate statistical analysis for some individual taxa of the community. In combination with toxicity and ecological data, ordination techniques can provide insight into effects of toxic substances in complex biological communities.

Published
1995
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24. An Evaluation of Four Types of Freshwater Model Ecosystem for Assessing the Hazard of Pesticides

Author

Leeuwangh, Peter, Brock, Theo C.M., and Kersting, Kees

Abstract

Experimental results are reported on four types of freshwater model ecosystem after administration of a single dose of chlorpyrifos. The fate, and primary and secondary effects of chlorpyrifos were compared between the model ecosystems, and were evaluated in the light of the predictive value of the current ecotoxicological hazard assessment procedure for pesticides. 'Slootbox', a fate model used in the ecotoxicological risk assessment of pesticides in the Netherlands, overestimated chlorpyrifos concentrations. The primary effects of chlorpyrifos can be predicted accurately on the basis of single species laboratory toxicity data. The population effects observed in the microecosystems, microcosms, and mesocosms were consistent between all experiments and with the single species tests. Community metabolism, as a functional endpoint, was less sensitive than the structural parameters measured. Secondary effects, both for structural and functional endpoints, varied between the micro- and mesocosm experiments. At the present 'state of the art' in ecotoxicology, no a priori prediction of secondary effects in natural ecosystems will generally be possible. 0.1 times the lowest acute L(E)C50for chlorpyrifos, as measured in the current ecotoxicological hazard assessment procedure, matched the NOECmesocosmfor a single dose of chlorpyrifos. Recovery of populations affected by insecticide stress was found to depend on factors such as life cycle characteristics and ecological infrastructure, in addition to the toxicant concentration. The onset of (potential) recovery is likely to start at an approximate concentration of the EC10(48 h).

Published
1994
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37. Quantitative structure-activity relationships and mixture toxicity studies of chloro- and alkylanilines at an acute lethal toxicity level to the guppy (Poecilia reticulata).

Author

Hermens J, Leeuwangh P, and Musch A

Subjects
Animals, Chemical Phenomena, Chemistry, Physical, Lethal Dose 50, Structure-Activity Relationship, Aniline Compounds toxicity, Fishes physiology
Abstract

Quantitative structure-activity relationships (QSARs) were calculated for the acute lethal toxicities (14-day LC50) to the guppy (Poecilia reticulata) of anilines, with several hydrophobicity characteristics and the Hammett sigma constant as parameters. Calculated and experimental Poct values and II constants were used as hydrophobicity characteristics. Introduction of Hammett constants improved the quality of the QSARs. Together with the QSAR studies the toxicities of mixtures of the anilines were determined. The toxicities of three mixtures did not deviate from concentration addition.

Published
1984
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39. Quantitative structure-activity relationships and mixture toxicity of organic chemicals in Photobacterium phosphoreum: the Microtox test.

Author

Hermens J, Busser F, Leeuwangh P, and Musch A

Subjects
Chemical Phenomena, Chemistry, Physical, Computers, Luminescent Measurements, Structure-Activity Relationship, Water Pollutants, Chemical toxicity, Photobacterium drug effects
Abstract

Quantitative structure-activity relationships were calculated for the inhibition of bioluminescence of Photobacterium phosphoreum by 22 nonreactive organic chemicals. The inhibition was measured using the Microtox test and correlated with the partition coefficient between n-octanol and water (Poct), molar refractivity (MR), and molar volume (MW/d). At log Poct less than 1 and greater than 3, deviations from linearity were observed. Introduction of MR and MW/d improved the quality of the relationships. The influences of MR or MW/d may be related with an interaction of the tested chemicals to the enzyme system which produces the light emission. The sensitivity of the Microtox test to the 22 tested compounds is comparable to a 14-day acute mortality test with guppies for chemicals with log Poct less than 4. The inhibition of bioluminescence by a mixture of the tested compounds was slightly less than was expected in case of concentration addition. The Microtox test can give a good estimate of the total aspecific "minimum toxicity" of polluted waters. When rather lipophilic compounds or pollutants with more specific modes of action are present, this test will underestimate the toxicity to other aquatic life.

Published
1985
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40. Joint toxicity of mixtures of groups of organic aquatic pollutants to the guppy (Poecilia reticulata).

Author

Hermens J, Leeuwangh P, and Musch A

Subjects
Aniline Compounds toxicity, Animals, Chlorophenols toxicity, Drug Interactions, Hydrocarbons, Chlorinated toxicity, Structure-Activity Relationship, Fishes physiology, Water Pollutants toxicity, Water Pollutants, Chemical toxicity
Abstract

In this study acute lethal concentrations (LC50) to the guppy (Poecilia reticulata) were determined for mixtures of 4 groups of aquatic pollutants. The groups were composed of 11 nonreactive, nonionized organic chemicals, 11 chloroanilines, 11 chlorophenols, and 9 reactive organic halides. Earlier studies indicated that the joint toxicity within each of these groups was concentration additive, probably because of a similar mode of action. The joint toxicity of combinations of one representative from each group showed a high variance, but generally tended to be partially additive to concentration additive. This high variance is probably caused by the low number of compounds in these mixtures. Experiments with mixtures of whole groups gave more accurate results. The toxicity of a mixture of the first three groups, containing 33 well-known aquatic pollutants, was almost completely concentration additive. Concentrations of 0.04 of the individual LC50 values contributed to the toxicity of this mixture.

Published
1985
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