Trichlorfon applicators

Trichlorfon is widely used in agriculture to protect plants, in sanitation and veterinary medicine. More information about trichlorfon applications can be found in Part 6. Trichlorfon is toxic however, it is less toxic than DDT, hexachlorane, thiophos and other pesticides. 

Other studies were conducted by the FS in 1976 to expand the data base on the size of drops which deposited on Douglas-fir needles. These studies provided an opportunity to determine if the drop size distribution would be similar to drop size distributions of tank mixes studied earlier. The 1976 study involved aerial application of acephate and trichlorfon, and the 1981 study involved Bacillus thuringiensis (Dipel 4L and Thuricide 16B). These data have not been published or reported previously. The chemical tank mixes were applied by helicopter and the B.t. tank mixes were applied by fixed-wing aircraft. 

It dissolves worse in diethyl ether and carbon tetrachloride. If stored for a long time, its aqueous solutions become acidic. The stability of trichlorfon largely depends on the pH of the medium at pH > 5.5 it slowly transforms into 0,0-dimethyl-0-(2,2-dichlorovinyl)phosphate, which finds an increasing application in agriculture and household. 

Few experiments in field conditions have been reported. The earliest one showed that a population of M rotundata females reared in an alfalfa field was not reduced significantly after a treatment with trichlorfon in late evening. However, the number of cells completed per day was reduced during the post-treatment period (Figure 7.4) and the number of dead immature individuals was a maximum the day following application. It was concluded that trichlorfon was a short residual substance [58]. In a similar... 

The fecundity of M. rotundata females foraging in a field sprayed with trichlorfon was significantly affected, since 4 days after application the number of cells completed per female dropped by 66 percent compared to control [58]. 

Torchio, P.F. (1983). The effects of field applications of naled and trichlorfon on the alfalfa leafcutting bee. Megachile rotundata (Fabricins). I. Kansas Entomol. Soc. 56, 62-68. 

In this report tests of operator exposure were conducted with the Nice N Green Company and ChemLawn Corporation. Studies to evaluate potential applicator exposure to diazinon (0,0-diethyl 0-[methyl-2-(I-methyl ethyl)-4-primidinyl]phosphorothioate) insecticide were made on 3 August, 18 and 28 September, 1979 and for the insecticide trichlorfon (dimethyl 2,2,2, trichloro-I-hydroxy-ethyl) phosphonate) on 5 September, 1979. 

The following data were collected from each of four exposure studies. Three were for diazinon and one for trichlorfon exposure. All studies were made under actual conditions normal for the application procedure. 

Location Indianapolis, Indiana Date of application 5 September 1979 Insecticide Dylox (trichlorfon) wettable powder Application rate 8 lbs. ai/acre... 

There appears to be no available TWA or TLV-STEL for trichlorfon. However, based on the organophosphate level as established for diazinon, the concentrations of 0.002 for the total work day and 0.007 yg/m for the application time were low. A concentration of 0.109 yg/m was measured during tank preparation. The TWA limit is 0.I yg/m . 

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