Why can biological pest control be less harmful to the environment than chemical pesticides?

Biological pest control is often considered less harmful to the environment than chemical pesticides because it avoids the widespread ecological damage associated with synthetic chemicals.12

Chemical pesticides, particularly broad-spectrum varieties, can be toxic to a wide range of organisms beyond the intended pests. Their use often leads to:23

• Environmental Contamination: Persistent chemicals can accumulate in soil and contaminate groundwater or surface water through runoff.24
• Disruption of Food Chains: Chemicals can build up in the tissues of organisms, causing toxic effects in wildlife, such as birds of prey, that occupy higher levels of the food chain.2
• Harm to Beneficial Species: Pesticides may inadvertently kill natural predators or parasites that help keep pest populations in check, potentially worsening the problem.12
• Development of Resistance: Repeated chemical use can lead to pest populations evolving resistance, requiring even more intensive intervention.2

In contrast, biological control utilizes natural enemies—such as predators, parasites, or specific diseases—to manage pest numbers. By focusing on targeted, ecologically based methods, this approach minimizes the risk of toxic residues and unintended harm to the broader environment.5162