How to Effectively Control Pesticide Residues in Chinese Medicinal Herbs
When pesticides are sprayed onto crops or soil, after a period of time, due to the effects of light, natural degradation, rain, high-temperature volatilization, microbial decomposition, and plant metabolism, the vast majority have disappeared, but trace amounts of pesticide residues will remain. Residual pesticides are ineffective against diseases, insects, and weeds, but they can cause harm to people who use them directly or indirectly for treating diseases. As the scope and amount of pesticide use continue to expand, controlling pesticide residues and ensuring the safety and health of humans and livestock has become a problem that needs to be solved. So, how can pesticide residues be controlled to the greatest extent possible?
1. Rational Use of Pesticides: Pesticides should be applied dialectically according to the different harvested parts of Chinese medicinal herbs, the properties of the pesticides, and the occurrence and development patterns of diseases, insects, and weeds, striving to achieve the greatest control effect with the smallest dosage. Rational pesticide use generally should pay attention to the following issues: 1. Use pesticides for the right target, grasp the critical period for application and the most effective application method; 2. Pay attention to the concentration and dosage of the pesticide, and master the correct application amount; 3. Improve pesticide performance, such as adding surfactants to improve the spreading performance of the spray solution; 4. Reasonably mix pesticides.
2. Safe Use of Pesticides: In accordance with the "Good Agricultural Practice for Chinese Medicinal Materials" (GAP), the "Regulations on the Safe Use of Pesticides", the "Standards for the Safe Use of Pesticides", and other regulations, prevention should be the priority and integrated control should be adopted. In particular, highly toxic and high-residue pesticides must not be used on Chinese medicinal herbs, and pesticides must be applied within the safe interval period.
3. Adopt Avoidance Measures: In areas severely contaminated by pesticides, crops that readily absorb pesticides should not be planted for a certain period of time; new crop varieties resistant to diseases and insects can be cultivated to reduce pesticide application.
4. Integrated Control: Actively carry out agricultural control and biological control, and implement rational crop rotation and stubble rotation. Actively develop high-efficiency, low-toxicity, and low-residue pesticide varieties, and prohibit the use of obsolete pesticide varieties.
5. Master the Harvest Period: It is strictly forbidden to harvest and sell Chinese medicinal herbs within the safe interval period. Because various agents decompose and disappear at different rates, and the growth trends and seasons of medicinal materials also differ, they have different safe interval periods. At harvest, the longer the time since the last spraying of the medicinal material, the better.
6. Carry Out Decontamination Treatment: Pesticides remaining on the surfaces of crops, fruits, and vegetables can be subjected to decontamination treatment. Methods such as sun exposure and washing can also reduce or remove pesticide residue contamination.