Carbofuran, insecticidal activity

This compound was much less toxic to the white mouse but comparable to carbofuran in insecticidal activity. Toxicological properties for some of these compounds are presented in Table III. It is apparent from the data that the thiobiscarbamates... 

G formulation. In related work with aldicarb, Coppedge et al. (21) concluded that slow-release formulations may extend bioactivity over a longer time but not improve efficacy of compounds with moderate or low insecticidal activity at normal application rates. Pertinently, of the currently registered soil insecticides, carbofuran is the least toxic to CRW (22.), and therefore, rate of release would be critical to its bioactivity. 

There is a great deal of activity in the synthesis of 2,2-dimethylbenzofm-ans such as Carbofuran (179). Carbofuran is a systemic insecticide active against flies, aphids, larvae, and mosquitos. 

Cambon, C., C. Declume, and R. Derache. 1979. Effect of the insecticidal carbamate derivatives (Carbofuran, Pirimicarb and Aldicarb) on the activity of acetylcholinesterase in tissues from pregnant rats and fetuses. Toxicol. Appl. Pharmacol. 49 203-208. 

Sahoo, A., Sahu, S.K., Sharmila, M., and Sethnnathan, N. Persistence of carbamate insecticides, carbosulfan and carbofuran in soils as influenced by temperature and microbial activity. Bull Environ. Contam. Toxicol, 44(6) 948-954, 1990. 

Carbosulfan, CGA-73,102, and ONCOL are derivatives of carbofuran (2,3-dihydr0-2,2-dimethylbenzofuran-7-yl methylcarbamate) which have broad spectrum activity similar to that of carbofuran but are substantially less toxic to mammals. CGA-73,102 is particularly effective as a soil insecticide by both contact and systemic action (9). Thiodicarb (10) and U-56,299 (11) are highly effective lepidopterous larvicides but are less toxic to plants and mammals than me thorny 1. U-56,299, with a rat acute... 

Owls are, however, threatened by other activities of humans. They are exposed to toxic chemicals in forestry and agriculture, and this has taken a toll on some species of owls. Burrowing owls, for example, have been poisoned by exposure to the insecticide carbofuran, which is used to control epideirric populations of grasshoppers in prairie agriculture. 

In collaboration with 5IPCAM (Italia) we studied the synthesis and activity as insecticides of two new types of Carbofuran derivatives (V) et (VI) depicted in scheme 154 (Ref. 209, 210). 

The most important inhibitors of CarbEs are organo-phosphorus insecticides (malathion, parathion, para-oxon, methyl parathion, EPN, and others), nerve agents (DFP, soman, sarin, tabun, and VX) and carbamate insecticides (carbofuran, carbaryl, aldicarb, propoxur, oxamyl, methomyl, and others). Organo-phosphorus toxicants inhibit CarbEs irreversibly by phosphorylation and carbamates inhibit CarbEs reversibly by carbamylation similar to the basic mechanism (i.e., acylation of the active site) ... 

The reactions show some typical oxidations of insecticides catalyzed by CYP enzymes. Carbofuran is hydroxylated to another active compound carbaryl is demethylated or hydroxylated and aldrin is epoxidated to diel-drin, which also has insecticidal properties. Phosphorothionates must be oxidized to the phosphates by CYP enzymes in order to become inhibitors of acetyl cholinesterase. Parathion-methyl is transformed to the oxon analogue, paraoxon-methyl, which is the toxic compound. It also can be demethylated to the inactive desmethyl-parathion-methyl. 

To examine the effect of initial concentration on the development of activity, four soil types were initially treated with five levels of carbofuran ranging from 0.01 to 100 ppm. The results of the subsequent activity tests are summarized in Table V. Concentrations of 1 ppm were sufficient to cause activity to develop in the three mineral soils. Concentrations in excess of 1 ppm were required for the organic soil. Activity appears to develop quickly over a broad range of conditions that one would encounter naturally during use of the insecticide. 

Cultivation treatments of carbofuran (Furadan 15G, 1.12 kg Al/ha) were made four to six weeks after planting, when CRW larvae were actively feeding on corn roots. Plastic tubes, positioned directly in front of the cultivator sweeps, directed the insecticide to both sides of the corn row where soil was thrown over the granules to effect incorporation. For planting-time applications, Furadan 15G (1.12 kg Al/ha) was placed in an 18-cm band in front of the firming wheels and incorporated with a drag chain. 

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