This is a measure of a substance’s ability to remain as a discrete chemical entity in the environment for a prolonged period of time. A common measuring tool for persistence is “half-life” (t1/2), which is the amount of time required for half of the substance to break down. If halflife is greater than 30 days in the air, or if half-life is greater than 50 days in soil, water, or any other media, the substance is considered to be persistent.
Source: MBDC
Category: Green