Die Bodenkultur - Journal for Land Management, Food and Environment


The Occurence of Pesticides in the Air


The volatilization of pesticides from model surfaces (glass-beads) was investigated in laboratory trials, which showed that 20 % of the total quantity of Parathion and Methidathion, 56 to 73 % of Mevinphos, 12 to 21 % of Chlorpyriphos and Pendimethalin, 5 to 14 % of Fenitrothion and 16 to 80 % of Lindane are lost by volatilization within 24 hours after the application. Atrazin, however, did not evaporate in significant quantities from glass beads in laboratory trials. Much higher volatilization rates than those produced in laboratory trials were observed in field trials 24 hours after the applications of Mevinphos, Atrazin and Lindane in cultures of sunflowers and sugarbeets. The evaporation of pesticides from deposits on foliage mounted up to 46 % Atrazin, 54 % Lindane and 89 % Mevinphos. Volatilization of 2,4-D from glass surfaces in a greenhouse resulted in typical symptoms produced by plant-growth regulators in sensitive testplant species. No such effects could be induced in fieldtrials with herbicides. This leads to the supposition that the concentrations of herbicides in the air are much too low to cause damage in plant cultures. As there is still insufficient data and theoretical development concerning the quantities of pesticides evaporating, their behaviour and their persistence in the air, available, no precise risk assessment of their impact on human beings and the environment can be given.