What to Do About Expired Pesticides? Learn How to Avoid Using Expired Pesticides
Every pesticide has a certain shelf life, and it can only be used safely and effectively within that shelf life. Once a crop is treated with a pesticide past its shelf life, not only will it fail to control disease and kill pests, but it will also cause pests and diseases to develop resistance, miss the best time for prevention and control, and make control difficult or impossible. More importantly, it will cause phytotoxicity to the crops, leading to irreparable consequences. Therefore, farmers must never use expired pesticides. So, how can you avoid using expired pesticides?
Check the production date clearly when buying pesticides
Be sure to buy pesticides from legitimate agricultural supply outlets. When purchasing, first check clearly the pesticide variety you intend to buy, then check clearly the production date and the product instructions, because all pesticides have a shelf life. If you find a pesticide past its shelf life, do not buy it under any circumstances. For pesticides close to their shelf life, try to buy only as much as you will use, and use them right after purchase.
Do not use leftover pesticides at home that are past their shelf life or that have no solid evidence proving they are still effective
If a farming household still has pesticides left over from last year, before using them this year, first check clearly whether the label is intact and whether they are still within the shelf life. If you find pesticides past their shelf life, it is best not to use them. If the label of the leftover pesticide has fallen off and you cannot confirm the pesticide variety, do not use it wrongly or carelessly, so as to avoid causing phytotoxicity to crops and greater economic losses.
Put labels on leftover pesticides
Leftover pesticides stored by farming households must have a complete bottle label, with the pesticide name, batch number, production date and shelf life clearly legible. If the bottle label is damaged, the farming household must write down the pesticide's shelf life and precautions for use and stick it on the outer packaging of the pesticide.
Store leftover pesticides properly
Improper storage of leftover pesticides will reduce their insecticidal effect and may even cause phytotoxicity. Therefore, if a farming household has not used up the pesticides bought this year and plans to use them next year, the following points should be observed during storage:
1. Keep sealed: Some pesticides volatilize easily and lose effectiveness, causing air pollution. When storing, be sure to tighten the bottle cap and keep them sealed.
2. Maintain temperature: Most powder-form pesticides are prone to having their quality affected under high temperatures. The higher the temperature, the easier it is for pesticides to melt, decompose, volatilize, or even burn and explode. Some emulsion pesticides, when exposed to high temperatures, will also have their emulsifying properties destroyed, reducing their efficacy. And some liquid pesticides in bottles freeze when exposed to low temperatures, forming lumps, or cause the bottles to crack. When storing such pesticides, the indoor temperature should be kept above 1°C.
3. Avoid light: Some pesticides are sensitive to light. Long-term exposure to light and sun will cause the pesticides to decompose, deteriorate and lose effectiveness. When storing, avoid high temperatures and sunlight.
4. Keep dry: Powder-form pesticides and plant regulators easily absorb moisture and cake. Therefore, the place where pesticides are stored should be kept dry, strictly preventing rain leakage and snow drifting in. Windows should also be left for ventilation and air exchange, maintaining the relative humidity below 75%.
5. Avoid mixed storage: Pesticides are divided into alkaline, acidic and neutral types. Alkaline pesticides include propanil, lime sulfur mixture, Bordeaux mixture, etc.; acidic pesticides include deltamethrin, etc.; neutral pesticides include hinosan, etc. These three pesticides of different properties must be stored separately when being stored, with a distance of more than 0.5 m, otherwise the pesticides will deteriorate and lose effectiveness.
6. Strictly avoid mixed packaging: Two pesticides left over from the year that have not been used up must not be mixed in one bottle, to avoid loss of effectiveness.