Pesticide Storage: Avoiding Point-Source Contamination
Montana State University
You can simplify your life when buying pesticides such as herbicides, fungicides, or insecticides, by purchasing only enough for the job at hand or what you know you will use in one season. This avoids the issue of storage or disposal.
However, in those instances when you do have pesticides left over, proper storage is important. Pesticide containers that are stored for long periods of time on the damp ground of a shed, for example, can rust out or fall apart when lifted. This can result in large amounts of toxic material concentrated in a very small area. This is called point source contamination. Point source contamination can lead to ground- and surface water contamination as well as presenting a hazard to persons or animals in the area. In addition, many stored pesticides become outdated, ineffective, or are impossible to identify if stored in containers other than the original or if the label deteriorates or is lost.
To properly store a pesticide, first read the label to see if it will be affected by high temperatures or freezing. If so, store where those conditions will not occur. Make sure the conditions are dry to avoid rusting or deterioration of containers. Don't store solution that has been mixed with water or other materials, and store the pesticides in their original containers. And finally, store the products in a locked storage area, out of reach of children.