Researchers studied the degradation effect of humic acid on organophosphorus pesticides. In the research example, the decomposition rate of methyl parathion mixed with humic acid in a ratio of 10:3 and methyl parathion without humic acid was compared with that of methyl parathion after 15 days at 40°C. The decomposition rates of pesticides after 30 days at 40°C were 5.8% and 29.7%, respectively. This example shows that the decomposition rate of methyl parathion under experimental conditions can be reduced by 80%.
The test of four other commonly used pesticides with different ratios of humic acid at 40°C for 30 days found that humic acid had a significant effect on reducing the decomposition rate of the tested pesticides.
There are reports on the release rates of pesticides such as methyl parathion carried by humic acid and its salts under different conditions. The results show that when humic acid and methyl parathion are in different ratios, there are different release rates, and the release rate becomes slower as the amount of humic acid increases.
