Causes of pesticide residues
There are many reasons that lead to and affect pesticide residues. The main factors affecting pesticide residues are the nature of pesticides, environmental factors and the use of pesticides.
Pesticide properties and pesticide residues
Pesticides, such as organic arsenic and mercury, have been banned from the environment and plant bodies because of their metabolites arsenic and mercury that are ultimately unable to degrade.
666, DDT and other organic chlorine pesticides and their metabolites are stable in chemical properties, slow in digestion in crops and environment, and easy to accumulate in human and animal body fat. So although the organochlorine pesticides and their metabolites toxicity is not high, but they are still residue problem.
The chemical properties of organophosphorus and carbamate pesticides are unstable. After application, they are easily decomposed by the influence of external conditions. But there are some highly toxic and highly toxic species of organophosphate and carbamate pesticides such as methamidophos, parathion, aldicarb, G Budweiser, optunal, if be short growth period, continuous harvest of vegetables for, it is difficult to avoid the residual amount exceed the standard caused livestock poisoning.
In addition, a part of the pesticide though itself has low toxicity, but the production of impurities or metabolites residues is higher, such as impurities generated during the production of two thiocarbamate fungicide and the metabolite ethylenethiourea is carcinogenic, three chlorine impurities in alcohol DDT kill mites, Ding Liuke Budweiser, C Liuke Budweiser main metabolic detective Budweiser and Budweiser 3- hydroxy grams.
The internal absorbability, volatility, water solubility and adsorbability of pesticides have a direct impact on the residues in the surrounding environment of plants, atmosphere, water and soil. Environmental factors such as temperature, light, rainfall, soil pH and organic matter content, vegetation condition and microorganism also affect the degradation rate of pesticide and affect pesticide residues to some extent.