Which of the following is NOT a consequence of pesticide incompatibility?

• A. Enhanced rate of biodegradation in soil
• B. Loss of effectiveness against target pests
• C. Phytotoxicity (injury to plants)
• D. Increased hazard to the applicator or treated animals

Answer: (A)

Incompatibility between pesticides means that when two products are mixed, chemical reactions or physical incompatibilities can occur that change how the mixtures behave. These reactions can inactivate one or both products, form harmful degradation products, or create conditions that injure plants or raise risks to people and animals. That often shows up as reduced effectiveness against target pests, or phytotoxicity to crops, and can also increase hazards for the applicator or treated animals because the mix may be more toxic or volatile. An enhanced rate of biodegradation in soil isn’t a typical or reliable outcome of incompatibility; incompatibility is more commonly associated with loss of efficacy, plant injury, or increased risk, rather than faster breakdown in the soil.