The behaviour of pesticides was investigated at different intensities of crop management for the assessment of pesticide persistence after long-term application. A crop rotation of sugar beets - winter wheat - winter barley has been conducted over several vegetation periods (1987-1989). Variations of agricultural practice have been followed, namely a. extensive plant production using a minimum of means of production, b. integrated plant production in order to obtain an economic optimum of crop yield using a minimum amount of means of production and c. conventional plant production using registered products and dosages of pesticides and fertilizers in order to obtain maximum yield.During the 3 vegetation periods, the residue dynamics mainly of anilazine, carbofuran, chloridazonc, ethofumesate, fenpropimorph, isoproturon, lindane, metamitron, pendimethalin, phenmedipham, pirimicarb, procbloraz, Propiconazol, triadimefon, triadimenol and tri-allate have been studied preferably in the 0-5 and 5-10 cm soil layer.In the top layer of the soil (0-5 cm) the residue level of the herbicides did not exceed a maximum concentration level of 1-3 mg a. i./kg soil immediately after application while the maximum of the residual amounts of the insecticides and fungicides were about 0.1-1 mg a.i./kg soil, depending on the amounts applied.Some groups of pesticides can be classified according to their dynamical behaviour: - The residual amounts of anilazine, chloridazone, ethofumesate, fenpropimorph isoproturon, metamitron, phenmedipham, pirimicarb, propiconazol and triadimenol declined during the vegetation period below the limits of detection. - Other compounds like pendimethalin, procbloraz, and tri-allate persisted in the soil for more than one vegetation period at a very low concentration level. Some pesticides like anilazine and isoproturon could not be detected in the soil even within a 4-12 weeks period after application.The different intensities of crop management did not affect pesticide persistence but the influence of weather conditions was dominant.

Dieser Beitrag geht der Frage nach, inwieweit die gegenwärtig erhebbaren Daten die Kontamination eines definierten Bodenareals hinreichend zu bewerten gestalten. Die für diese Fragestellung benötigten und erhebbaren Daten wurden tabellarisch zusammengestellt. Daraus wurde abgeleitet, welche Aussagen für die Risiko-Bewertung einer konkreten Kontaminationssituation auf einem definierten Bodenstandort getroffen werden können.

Mit dem Ziel, die wesentlichen HPLC-spezifischen rückstandsanalytischen Daten von Pflanzenschutzmitteln aus Originalarbeiten zugänglich zu machen, veröffentlicht in den wissenschaftlichen Zeitschriften der Chromatographie, Chemischen Analytik und Umweltwissenschaften, wurde die Faktendatenbank „HPLC DATABASE” mittels eines menügesteuerten, in dBASE IV geschriebenen Daten-Verwaltungsprogrammes erstellt. Die Datenbank wird nach ihrer Fertigstellung die meisten Originalarbeiten, zurückgehend auf das Jahr 1973, erfassen und mit Neuerscheinungen aktualisiert.

The vapour phase extraction technique according to Bleidner has been applied to the trace analysis of organochlorine pesticides and PCB in water sediments. This method eliminates time consuming drying, extracting, and clean-up steps in comparison with the conventional (Soxhlet) methods. The method developed is sufficiently sensitive and shows satisfying recovery results — with the exception of γ-HCH. Low yields of the DDT family are not caused by artifacts but are rather due to irreversible adsorption to sediment and fast metabolizing power of this substrate.

Toxicity values were obtained for pentachlorophenol (PCP) and other compounds in the standard OECD and EEC earthworm test. To help explain the uptake and bioaccumulation mechanisms of PCP which affect toxicity, experiments have been conducted using the earthworm Allolobophora caliginosa. The experiments showed that radiolabelled PCP and its sodium salt, PCP-Na, were taken up rapidly by the earthworms during 24 h from aqueous solution (1 and 10 micrograms ml-1) in a limited volume (5 ml) to give a bioconcentration factor (BCF) of 2.5, and that the solution concentration had no apparent influence on uptake. Exposure of worms over a period of 14 days in a large volume of soil under laboratory conditions increased the BCF, which was approximately 8 and 13 in the low (2.2 mg g-1 soil) and high (11.2 mg g-1 soil) soil concentration respectively. Longer exposures of the same worm species for 131 days in another soil type, in lysimeters under outdoor conditions, did not increase the BCF beyond that reached after 14 days exposure in the artificial soil. There were differences between earthworm species in their bioconcentration ability: Lumbricus terrestris accumulated 3 times more radiocarbon than A. caliginosa. Irrespective of the concentrations in solution, the binding of free phenol (PCP) in worm tissues was greater than for its sodium salt (PCP-Na), but there were no apparent differences in the amount of these substances eliminated, which was rather low. Metabolic studies have shown that PCP is metabolised more rapidly than PCP-Na in the worms body, resulting in the formation of metabolites which are polar in nature and also probably of conjugates. The results are discussed in relation to the mechanisms which may be responsible for the detoxification of PCP in earthworms.

Deutlich vor Beginn des Pilotprojektes Umweltprobenbank fiel der Berliner Arbeitsgruppe innerhalb der Biologischen Bundesanstalt die Aufgabe zu, nach den Haltbarkeitsbedingungen für Pflanzenmaterial über eine überdurchschnittlich lange Aufbewahrungszeit zu suchen, wobei insbesondere die Spurengehalte organisch-chemischer Fremdchemikalien zu beobachten waren.

An urban terrestrial microecosystem has been used under outdoor conditions to study the transfer of chemical residues within the system components. The microecosystem consisted of soil monoliths obtained from a site with an established vegetation cover dominated by goldenrod, Solidago gigantea. The microecosystem contained integrated food chain elements composed of primary producers, herbivores and carnivores. The system was stocked with indicator insect species, snails (Cepaea nemoralis) and earthworms (Allolobophora caliginosa), captured from the original site. Evaluation of the system was made using radiolabelled sodium pentachlorophenate (PCP-Na) which was applied as a single application at an equivalent rate of 5 kg ha-1. The mass balance revealed that, after 131 days, in the autumn, and after 222 days, in the winter, that 43 and 39% radiocarbon, respectively, was recoverable from the microecosystem. The unaccounted radiocarbon was very probably removed through volatilization and photomineralization of the compound. PCP residues on foliage decreased rapidly, 50% of which were metabolised within 15 days. Most of the radiocarbon remaining in the system after 131 days was in the top soil and plant litter, transmitted mainly through washing off by rain and leaf litter fall. There was a variation in the uptake of PCP-Na residues in the food chain organisms, where the total radiocarbon concentrations during the first 19 days of exposure ranged, e.g. in snails, from 3 to 0.6 micrograms g-1, in springtails from 5 to 105; in beetles (Amara fusca) from 3 to 1, in spiders from 13 to 11, and in harvestman from 31 to 77 micrograms g-1. The ecological magnification indices (EM) of all the organisms with respect to their main food source, i.e. plant litter, demonstrated no bioconcentration effects. This is attributed to the metabolism of PCP-Na by the organisms and its rapid excretion. The urban wasteland ecosystem contained in outdoor lysimeters employed as a model gives valuable information and has considerable value in predicting the ecological fate of industrial chemicals.

The fungicide (/sup 3/H)imazalil was formulated as a seed dressing in a one and a four component product; the latter corresponding to Drawigran plus. After dressing of spring barley seeds with the one and the four component formulation, they were sown and grown in outdoor lysimeters to study the influence of the other three components fenfuram, thiabendazol and quintozen on the uptake and metabolism of imazalil in plants and soil. The uptake of (/sup 3/H)imazalil in shoots at the tillering stage of growth was 4.3 and 2.8% in the one and four component seed dressings, respectively. Out of the total amount taken up, only about 14 and 4%, respectively, was the intact imazalil present at this stage. The root uptake was 5.7% from the one component and 4.3% from the four component mixture of the initial applied radioactivity, and the amount of unchanged imazalil fraction in this was 40 and 32%, respectively. These differences in uptake and metabolism were consistent till the deadripe stage of growth. The grains, ear-chaff and straw contained together a total of 1.10 and 0.94% of the initially applied radioactivity in the one and four component formulation, respectively. The grains, thus, had a total residue content (imazalil + metabolites) of less than 0.001 mg/kg. The soil retained about 79% of the applied radioactivity in each of the two experiments and 60% (0.04 mg/kg dry soil) of this was localized in the upper soil layer (0-3 cm). About half of this, was the unchanged imazalil present after one vegetation period in both cases.

Es wird ein Verfahren zur jahrelangen Tieftemperaturlagerung biologischer Proben aus dem Pflanze/Boden-Bereich mit organisch-chemischen Kontaminanten beschrieben, das den Bedarf sowohl der Rückstandsanalytiker als auch die Bedürfnisse von Umwelt-Bewertungsstellen erfüllt. Zu diesem Zweck wurde biologisches Probenmaterial unter verschiedenen Tieftemperaturbedingungen in unterschiedlichen Behältnistypen eingelagert und in Intervallen untersucht.

Our previous method for the determination of insecticide residues in bees is now supplemented by an additional one for 9 pyrethroids used in the Federal Republic of Germany. By this method, the pyrethrum insecticide components may also be analysed. In absence of singular standards, the pyrethrum insecticides are quantified as sum. The minimum detectable amounts of the gas Chromatographic method range between 0.01 and 1 μg/g and the mean recoveries from 76 to 103%. The literature survey about residue analytical methods for bees given in part I of this series has been completed.

A standard screening procedure using sterile soybean and wheat cell suspension cultures has been developed to study the metabolic profiles of established xenobiotics as well as new synthesized compounds. This short term test provides quantitative data on the distribution of metabolites and the parent compound between the nutrient medium and the plant cells, on the amount of more and less polare metabolite fractions in comparison to the parent compound and the amount of substance bound or irreversibly absorbed to the extracted cell fragments. From this data turnover rates are calculated for ranking purpose. Results obtained for 2,4-D, PCP, DEHP and monolinuron as model substances are presented and compared with data from other environmental tests.

The described methodology allows the determination of metabolic turnover, biomineralization and volatilization of organic environmental chemicals. The overall accountability of radiolabelled chemicals with standardized soybean and wheat cell cultures determined is nearly quantitative. The total balance of the radiolabelled dichlofluanid, 2,4-dichlorophenoxyacetic acid, monolinuron, lindane, parathion and pentachlorophenol recovered by this method are reported.

A guideline is drafted describing the screening procedure in detail. The aim for this is to facilitate an adoption of this test by bodies supervising environmental chemicals. Successful introduction of this method into the respective laboratories will cause no problems, as the procedure has been collaboratively established and improved.