What aspect of granular herbicides reduces toxicity to fish?

Granular herbicides are formulated in a way that minimizes their toxicity to aquatic life, particularly fish. A key factor in this is the low concentration of active ingredients present in granular formulations. When these herbicides are applied, their lower concentrations decrease their potential to exert harmful effects on non-target organisms in aquatic environments.

In contrast, higher concentrations would increase toxicity, and immediate dissolution could lead to a rapid release of active substances into the water, elevating the risk of negative impacts on aquatic species. Aggregation with soil may help to contain the herbicides closer to the application site but doesn't primarily address the inherent toxicity of the herbicide itself in relation to aquatic organisms. By having a lower concentration, granular herbicides are designed to target specific pests while posing minimal risk to other forms of life, particularly aquatic ones.