Pathways of pesticide spread in the environment

Biological breakdown most common

In what ways and how quickly are the substances broken down? The risk of accumulation and spread in the environment decreases the faster a pesticide is broken down. Breakdown of pesticides can occur in the plant, air, soil and water, mainly in one of three ways:

• Photochemical breakdown: Ultraviolet solar radiation breaks down chemical bonds. As a rule the breakdown is not complete and leads to the formation of breakdown products.
• Chemical breakdown: Occurs mainly in soil water and is affected to a great extent by the degree of acidity in the soil (pH)
• Biological breakdown: Is the most common form of pesticide breakdown in nature. Occurs in plants, in the soil and in water. Microorganisms such as bacteria and fungi, with the help of their enzymes, are responsible for most of the breakdown.