Pesticide characteristics Many plant-derived pesticides(e.g, pyrethrin from chrysanthemums)or their derivatives are easily broken down by microorganisms and do not persist long in the environment Most of the second generation man-made pesticides (e.g., DDT)are broad spectrum and slow to degrade(half-life 15 years in soil and as much as 150 years in aquatic environments)Pesticide Characteristics Many plant-derived pesticides (e.g., pyrethrin from chrysanthemums) or their derivatives are easily broken down by microorganisms and do not persist long in the environment. Most of the second generation man-made pesticides (e.g., DDT) are broad spectrum and slow to degrade (half-life 15 years in soil and as much as 150 years in aquatic environments)