nonchemical

Nonchemical is an adjective used to describe methods, products, or processes that do not rely on chemical substances or chemical reactions to achieve their intended effect. The term is often used across disciplines to distinguish approaches that are physical, mechanical, biological, or behavioral from those that depend on chemical agents such as pesticides, solvents, or additives. Because it is a broad, non-technical label, its precise meaning varies with context.

In pest management, nonchemical methods include sanitation, mechanical traps, physical barriers, crop rotation, and biological controls, often assembled into an integrated pest management program. In cleaning and maintenance, nonchemical or chemical-free approaches use high-temperature steam, abrasion, pressure washing, or microfiber materials rather than detergents or solvents. In agriculture and horticulture, nonchemical farming emphasizes soil health, biodiversity, and cultural practices to reduce pest and disease pressures without synthetic inputs. In health and wellness, nonchemical interventions include physical therapy, exercise, psychotherapy, and other modalities that do not employ pharmaceutical drugs or chemical treatments.

A related distinction is between nonchemical and natural or organic. Some products labeled natural may contain chemical substances derived from natural sources, and some nonchemical methods may not be suitable for all goals. The term can be criticized for vagueness and for masking tradeoffs, because even nonchemical approaches can have environmental or health impacts, and some chemical-free products may still be derived from or involve energy use, heat, or irradiation.

Because nonchemical strategies can be slower to achieve results and may require specialized knowledge to implement effectively, they are often used in conjunction with other methods. They are widely discussed in ecological, environmental, and public health contexts as part of minimizing chemical exposure, reducing environmental contamination, and promoting sustainable practices.

See also: integrated pest management, mechanical control, biological control, sanitation, chemical-free cleaning.