Soil effects, insecticides

Standard control practices developed within these limitations have taken all the various factors into consideration. Entomologists recognize the inadequacy of many of the recommended control measures. They have initiated the effort to develop new and more effective insecticides and welcomed the interest and assistance of others. The recent accelerated development of new insecticides has opened new fields and done much to stimulate public interest in insect control. Much more needs to be learned than to know that the new materials will kill insects, before their true worth can be determined. We must determine many things. Knowledge of the effect on beneficial insects, wild life, soil, and machines is important. Of greater importance is Are they safe for the operator and for those who handle and use the product ... 

Beall, M.L., Nash, R.G. (1972) Insecticide depth in soil - Effect on soyabean uptake in the greenhouse. J. Environ. Qual. 1, 283-288. 

It is important to remember that, for insecticides, enhanced degradation in Boil is not a new phenomenon, but only a newly observed one. It iB unreasonable to think that the effect of the first encounter between an insecticide and a soil microbial population in 1983 or 1989 would differ from that same encounter occurring in 1965 or 1970. It follows that, some soil applied insecticides were subjected to "enhanced degradation" within a few weeks of their introduction. Therefore, it iB unscientific to describe a particular chemical as "once having been a good material but now is of questionable value because enhanced degradative activity developed after a history of uBe". A more scientific... 

Laboratory results show that this compound is an effective insecticide, primarily for controlling larvae of Lepidoptera and Coleoptera, either by foliar or soil contact or soil systemic applications. Soil application is particularly worth noting because none of the current insect growth regulators has measurable systemic activity. 

DDT, a chlorinated hydrocarbon, is an effective insecticide and is relatively nontoxic toward humans. However, many insects became resistant to DDT, rendering it ineffective. DDT s excellent chemical stability became a liability. DDT became concentrated in the soil and eventually moved up the food chain, killing fish and birds, including the bald eagle. 

Stotzky, G. 2002. Release, persistence, and biological activity in soil of insecticidal proteins from Bacillus thuringiensis. In Letournear, D.K. and B.E. Burrows (Eds.), Genetically Engineered Organisms Assessing Environmental and Human Health Effects. CRC Press, Boca Raton, Fla. p 187-222. 

Regarding soils, a central issue is the persistence and movement of pesticides that are widely used in agriculture. Many different insecticides, fungicides, herbicides, and molluscicides are applied to agricultural soils, and there is concern not only about effects that they may have on nontarget species residing in soil, but also on the possibility of the chemicals finding their way into adjacent water courses. 

Tattersfield E (1928) The decomposition of naphthalene in the soil, and the effect upon its insecticidal action. Ann Appl Biol 15 57-80. 

Field test work with technically pure gamma isomer of hexachlorocyclohexane has been extensive and involved and is being continued. It was necessary to know such factors as insecticidal value in field applications as compared to other insecticides, as well as residual life, residue from the poison standpoint, and residual taste or odor factors. These factors have been worked out on numerous crops and some of the results are dealt wTith in this paper. Because the pure gamma isomer was found to be effective on insects in the soil as well as on insect infestations on plants, its residual life in soil of all types and effects on tuber and root crops were also of major importance. 

Gambrell et al. [14] have described a procedure for the recovery of DDT (also kepone and Permethrin) added to soil suspensions incubated under controlled redox potential and pH conditions. They studied the effect of time on the levels of the insecticides and their breakdown products. 

DDT, Kepone and Permethrin were added to soil and incubated under controlled pH and redox potential conditions to determine the effect with time on the levels of the insecticides and their degradation products. Samples were analysed using gas chromatography, pH and redox potential affected the persistence of pesticides to different degrees. The recovery of DDT was affected by redox potential but not by pH. The stability of Kepone was not affected by pH or redox potential but Permethrin stability was affected by both. 

Chapman RA, Tolman JH, Cole C. 1994a. The effect of multiple soil applications of disulfoton 011 enhanced microbial degradation in soil and subsequent uptake of insecticidal chemicals by potato plants. J Environ Sci Health Part B Pest Food Contamin Agric 29(3) 485-506. 

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