spinosyns

Spinosyns are a class of naturally derived insecticidal compounds produced by the soil bacterium Saccharopolyspora spinosa. They are used as broad-spectrum insecticides in agriculture, horticulture, and some home garden products. The most active members of the group are spinosyn A and spinosyn D, and commercial formulations often combine these as spinosad.

Chemically, spinosyns are macrocyclic lactones with two sugar moieties. They are produced by fermentation of the producing organism and occur as a family of closely related analogs, with spinosyn A and D being the primary active components in many products.

Mechanism of action: spinosyns target the nervous system of insects by binding to nicotinic acetylcholine receptors at a site that is distinct from that used by neonicotinoids. This interaction causes sustained neural excitation, leading to rapid paralysis and death in susceptible insects. The activity profile tends to be broad within many arthropod pests.

Uses and formulation: spinosyns are formulated as liquid concentrates, wettable powders, and ready-to-use sprays for crops, ornamentals, and some indoor pest control applications. They act primarily through contact and ingestion, and their effectiveness can depend on pest biology, developmental stage, and environmental conditions.

Safety and environmental considerations: spinosyns generally exhibit relatively low acute mammalian toxicity, but they can be harmful to aquatic invertebrates and may affect pollinators when exposure occurs on blooming crops. As a result, regulatory labels commonly include precautions to avoid application during bee foraging periods and to protect waterways, with guidance on timing and application methods to minimize non-target impacts.