Organochlorines/organophosphate

Supercritical extractions such as that illustrated in Procedure 12.3 have been used to extract phenols, organochlorine, organophosphate compounds, and amines from soil [9,10,12],... 

Decreased uptake as a mechanism of resistance was also observed in houseflies resistant to organochlorine, organophosphate, and carbamate insecticides. Resistant strains had higher total lipids, monoglycerides, diglycerides, fatty acids, sterols, and phospholipids in the cuticle than did the susceptible strain (Patil and Guthrie, 1979). 

Year Organochlorines Organophosphates Carbamates Pyrethroids Other... 

Pyrethroid pesticides were developed as synthetic versions of the naturally occurring pesticide pyrethrin, which is found in chrysanthemums. Most pyrethroids are safer than the organochlorines, organophosphates, and carbamates, although some synthetic pyrethroids are toxic to the nervous system. Pyrethroids have been modified to increase their stability in the environment, and many different pyrethroids are being used today. 

A number of pesticides are used in vast amounts in agriculture and horticulture each year. As a result, waters, soils, and plants are frequently contaminated with these substances, which therefore constitute one of the major sources of potential environmental hazards to man and animals through their presence and concentration in the food chain. Pesticides are classified according to their chemical structure into organochlorines, organophosphates, carbamates, triazine herbicides,... 

Fen valerate is a highly active contact insecticide which is very useful because it controls some strains which are resistant to organochlorine, organophosphate and carbamate insecticides. It has the structure shown below. 

Pesticides are further subdivided into classes of compounds. Historically, insecticides included the organochlorine, methyl carbamate, and organophosphate classes of pesticides. Herbicides comprise about 10—12 principal classes of compounds. Within each class of pesticide there may be several hundred active ingredients. 

Since the problems with DDT, organochlorine insecticides have largely been replaced by organophosphates. Early organophosphates developed in... 

Chemicals degraded by WRF include pesticides such as organochlorines DDT and its very toxic metabolite DDE [8, 9] and organophosphate pesticides such as chlorpyrifos, fonofos and terbufos [10] polychlorinated biphenyls (PCBs) of different degrees of chlorine substitution [11-13], some even to mineralization [14, 15] diverse polycyclic aromatic hydrocarbons (PAHs) in liquid media and from contaminated soils or in complex mixtures such as creosote [16-18] components of munition wastes including TNT and its metabolites DNT [19-23], nitroglycerin [24] and RDX [25]. 

Snyder JL, Grob RL, McNally ME, OostdykTS.The effect of instrumental parameters and soil matrix on the recovery of organochlorine and organophosphate pesticides from soils using supercritical fluid extraction. J. Chromatogr. Sci. 1993 31 183-191. 

Pylypiw HM Jr, 1993. Rapid gas chromatographic method for the multiresidue screening of fruits and vegetables for organochlorine and organophosphate pesticides. J AOAC Int 76(6) 1369-1373. 

Ito et al. (1995) examined the combined dietary administration to rats of 19 organophosphate pesticides and 1 organochlorine pesticide, aU permitted for use in Japan, each at its ADI level. The dietary exposure at this level did not enhance the development of diethyl nitrosamine initiated pre-neoplastic lesions whereas at 100 times the ADI, the number and area of lesions were increased. The authors concluded that the study provided direct support for the present use of the safety factor approach in the quantitative hazard evaluation of pesticides. 

The newest class of insecticide, pyrethroids, is loosely based upon the naturally occurring pyrethrum derived from chrysanthemum flowers. Synthetic pyrethroids were developed in the 1980s but the naturally occurring pyrethrum was first commercially used in the 1800s. The chemical structure of pyrethroids is quite different from organochlorines and organophosphates, but the primary site of... 

Methotrexate Organophosphate and organochlorine insecticides Ozone Polybrominated and polychlorinated biphenyls... 

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