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[en] In most instances residues must be determined by chemical or biochemical methods without the use of radioisotopes. These methods assume that the nature of the toxic cpmpounds present is known, and that they can be extracted in known yields. Neither assumption is easily validated except by using radioisotopes. The use of radioisotopes to investigate these problems is described, with examples taken from work on demeton, dieldrin and the fungicide triphenyltin acetate. (author)
[fr]
Dans la plupart des cas, les residus doivent etre determines par des methodes chimiques ou biochimiques, sans recourir aux radioisotopes. Ces methodes sont fondees sur l'hypothese que l'on connait la nature des composes toxiques presents et que l'on peut les extraire en quantites connues. Aucune de ces deux conditions n'est facile a realiser si ce n'est a l'aide de radioisotopes. L'auteur decrit l'utilisation des radioisotopes dans l'etude de ces problemes et donne des exemples tires de travaux sur le demeton, la dieldrine et un fongicide (l'acetate de triphenyltine). (author)[es]
En la mayor parte de los casos la determinacion de los residuos de insecticidas debe efectuarse por metodos quimicos o bioquimicos, sin emplear radioisotopos. Para estos metodos se parte de dos supuestos: que se conoce la naturaleza de los compuestos toxicos presentes y que esos pueden extraerse con rendimientos conocidos. Ninguno de estos supuestos puede justificarse facilmente si no es mediante el empleo de radioisotopos. El autor de la memoria examina este empleo de los radioisotopos y cita ejemplos tomados de trabajos efectuados con ios insecticidas Demeton y Dieldrin. y con el fungicida acetato de trifenilestatlo. (author)[ru]
V bol'shinstve sluchaev ostatochnye insektitsidy dolzhny opredelyat'sya khimicheskimi i biokhimicheskimi sposobami bez primeneniya radioizotopov. Pri primenenii ehtikh metodov predpolagaetsya, chto izvesten kharakter prisutstvuyushchikh toksicheskikh smesej i chto oni mogut byt' ehkstragirovany v izvestnykh kolichestvakh. Ni odno predpolozhenie ne mozhet byt' svobodno prinyato, esli ono ne podtverzhdeno radioizotopnoj metodikoj. Opisyvaetsya primenenie radioizotopov dlya issledovaniya ehtikh problem i privodyatsya primery, vzyatye iz rabot, svyazannykh s demetonom, dil'drikom i fungitsidnym trifenilatsetatom olova. (author)Source
International Atomic Energy Agency, Vienna (Austria); Food and Agriculture Organization of the United Nations, Rome (Italy); 526 p; Sep 1963; p. 185-193; Symposium on the Use and Application of Radioisotopes and Radiation in the Control of Plant and Animal Insect Pests; Athens (Greece); 22-26 Apr 1963; ISSN 0074-1884; 
; 3 tabs., 19 refs.
; 3 tabs., 19 refs.
[en] The marine polychaete worm, Nereis virens, is resistant to organochlorine pesticides. When exposed to each of five pesticides (endosulfan, chlordane, endrin, dieldrin, and DDT) in concentrations ranging from 0.03 mg/L (DDT) to 22.0 mg/L (chlordane), only endosulfan and chlordane killed Nereis. In comparison, the same compounds were much more toxic to another marine invertebrate, Crangon septemspinosa. The authors wondered if the resistance of N. virens to organochlorines was related to their response to hypoxia. N. virens is a sediment dweller often found in intertidal regions and consequently may experience periods of severe oxygen deprivation; varying degrees of hypoxia can initiate a switch to anaerobic energy metabolism. When N. virens encounter hypoxic conditions, they can also exhibit a compensatory ventilation response. In the present study, the authors measured the bioaccumulation of endosulfan, dieldrin, and DDT by N. virens under normoxic and hypoxic conditions
Journal
Bulletin of Environmental Contamination and Toxicology; ISSN 0007-4861; ; CODEN BECTA; v. 40(2); p. 170-177
; CODEN BECTA; v. 40(2); p. 170-177
[en] The effects of soil amendments on the phytoextraction of ΣDDT (DDT + DDD + DDE) from soil ([ΣDDT] ∼ 1500 ng/g) by a pumpkin variety of Cucurbita pepo ssp pepo were tested and the patterns of ΣDDT storage throughout the plant shoot were examined. The soil amendments did not increase the total amount of ΣDDT extracted into plant shoots, but new information about ΣDDT distribution in the plants was obtained. As observed previously, the ΣDDT concentration in plant leaves (mean 290 ng/g) was significantly lower than in plant stems (mean 2600 ng/g). Further analysis revealed that ΣDDT composition was consistent throughout the plant shoot and that ΣDDT concentration in leaves and stems decreased exponentially as distance from the root increased, which was previously unknown. This new information about the patterns of ΣDDT uptake and translocation within pumpkin plants highlights the need for appropriate plant sampling strategies in future POPs phytoextraction research. - Patterns of ΣDDT storage in a pumpkin plant are elucidated and specific surfactant and mycorrhizal soil amendments did not increase the total amount of ΣDDT phytoextracted into plant shoots.
Journal
[en] The mass transport budgets of 1,1,1-trichloro-2,2-bis(chlorophenyl)ethane (p,p'-DDT) and decabromodiphenyl ether (BDE-209) in the Pearl River Delta, South China were calculated based on previously collected data. Residual p,p'-DDT, mostly related to historical use, has largely settled into soil (780,000 kg), while the soil BDE-209 inventory (44,000 kg) is considerably smaller. Conversely, large amounts of BDE-209 currently used in numerous commercial products have resulted in a much higher atmospheric depositional flux of BDE-209 (28,100 kg/yr) relative to p,p'-DDT (310 kg/yr). The soil inventory of p,p'-DDT is predicted to decrease to half of its current value after 22 years, and the percent area containing soil p,p'-DDT at levels exceeding the effects range-medium (27 ng/g) will decrease from 40% to 20%. Finally, soil BDE-209 inventory will reach an equilibrium value of 940 tons in ∼60 years, when BDE-209 levels in 50% of soil will be above an equivalent risk guideline value (125 ng/g). - Highlights: → Transport budgets of p,p'-DDT and BDE-209 in the Pearl River Delta were built. → Dry aerial deposition is the dominant route to transport p,p'-DDT and BDE-209. → Soil inventory of p,p'-DDT is much larger than that of BDE-209. → Soil inventory of p,p'-DDT would decline to half of its current value in 22 years. → Soil BDE-209 inventory is expected to reach an equilibrium value in ∼60 years. - Regional dynamics of p,p'-DDT and BDE-209 in the Pearl River Delta (South China) are examined and used to predict temporal variances.
Journal
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