Carbofuran persistence

Gorder, G.W., PA. Dahm, and J.J. Tollefson. 1982. Carbofuran persistence in cornfield soils. Jour. Econ. Entomol. 75 637-642. 

Research on control failures during the late 1970 s and early 1980 s focused on carbofuran, a compound that had earlier provided excellent control and had captured a considerable share of the rootworm insecticide market (e.g. 20% of treated acres in Iowa in 1977)(9). Although some studies found no correlation between prior use of carbofuran and an enhanced rate of carbofuran degradation (10.11) both monitoring of field residues (12-14) and laboratory degradation tests (15-17) conclusively demonstrated enhanced microbial degradation as the cause of decreased carbofuran persistence in fields with histories of carbofuran use. Thus, a... 

Environmental. The A/-methylcarbamates generally are biodegradable and of low soil persistence with half-Hves for carbaryl and aldicarb of 1—2 weeks and of carbofuran of 1—4 months. Certain carbamates are highly toxic to birds with oral LD qS for mallard, eg, pheasant, in mg/kg carbofuran, 0.40, 4.2 mexacarbate, 3.0, 4.5 and methomyl, 16, 15 compared to carbaryl >2000. Fish toxicity of carbamates is generally low, but these compounds are extremely toxic to bees. In cases of human poisoning, atropine is a specific antidote. 

Brahmaprakash GP, Panda S, Sethunathan N. 1987. Relative persistence of hexachlorocyclohexane, methyl parathion and carbofuran in an alluvial soil under flooded and non-flooded conditions. Agric Ecos Environ 19 29-39. 

Arunachalam, K. and M. Lakshmanan. 1982. Translocation, accumulation and persistence of carbofuran in paddy, ground nut, and cotton. Bull. Environ. Contam. Toxicol. 28 230-238. 

Deuel, L.E., Jr., J.D. Price, F.T. Turner, and K.W. Brown. 1979. Persistence of carbofuran and its metabolites, 3-keto and 3-hydroxy carbofuran, under flooded rice culture. Jour Environ. Qual. 8 23-26. 

Getzin, L.W. 1973. Persistence and degradation of carbofuran in soil. Environ. Entomol. 2 461-467. 

Mathur, S.P., H.A. Hamilton, R. Greenhalgh, K.A. Macmillan, and S.U. Khan. 1976. Effect on microorganisms and persistence of field-applied carbofuran and dyfonate in a humic mesisol. Canad Jour. Soil Sci. 56 89-96. 

Greenhalgh, R. and Belanger, A. Persistence and uptake of carbofuran in a humic mesisol and the effects of drying and storing soil samples on residue levels, J. Agric. Food Chem., 29(2) 231-235, 1981. 

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. 

Venkateswarlu, K., Gowda, T.K.S., and Sethunathan, N. Persistence and biodegradation of carbofuran in flooded soils, J. Agric. Food Chem., 25(3) 533-536,1977. 

Williams, I.H., Brown. M.J., and Whitehead. P. Persistence of carbofuran residues in some British Columbia soils. Bull. Environ. Contam. Toxicol., 15(2) 242-243,1976. 

The lab half-life of carbofuran In six soils (each under 4 different levels of moisture and 2-3 different temperatures) was In the range of 5-261 days. After 28 days of aerobic Incubation In two of the six soils, parent carbofuran was the major extractable compound degradation products comprised <5% of the extractable material (65). However, under anaerobic (flooded soil) conditions, the degradation product carbofuran phenol was found to be the principal product and to persist (66). 

Mora, A., Cornejo J., Revilla, E., Hermosin, M.C. (1996) Persistence and degradation of carbofuran in Spanish soil suspensions. Chemosphere 32, 1585-1598. 

Aquino, G.B. Pathak, M.D. Enhanced absorption and persistence of carbofuran and chlordimeform in rice plants on root zone application. J. Econ. Entomol., 1976, 69, 686. 

Most soils have a pH ranging from 4 to 9. The degradation of pesticides such as organo-phosphates and carbamates is affected by the pH of the soil. Most organophosphates are hydrolyzed under alkaline conditions, but diazinon is unstable in acid soils. Carbamates such as carbofuran are also hydrolyzed under alkaline conditions. The persistence of neonicotinoids is primarily determined by the pH. Imidacloprid and thiamethoxam are hydrolyzed under alkaline conditions, whereas thiacloprid and acetamiprid are less stable... 

Any factors that stimulate the growth of soil microorganisms or that increase the availability of pesticides in soil will enhance the degradation of the chemical. Felsot et al. (1981) found that the persistence of carbofuran was inversely correlated with microbial activity in corn-cropped soils. Tu and Miles (1976) reported that 88% of parathion was lost from soil in 7 months diazinon, 92% lost in 20 weeks paraoxon, 100% hydrolyzed in 12 hr mala-thion, 50-90% lost in 24 hr and carbofuran, 50% lost in 3-50 weeks. 

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