Ecotoxicity of bioinsecticide spinosad to soil organisms: Commercial formulation versus active ingredient

Comp Biochem Physiol C Toxicol Pharmacol. 2025 Jan:287:110056. doi: 10.1016/j.cbpc.2024.110056. Epub 2024 Oct 21.

Abstract

Spintor® (SPIT®) is a commercial formulation of a bioinsecticide with the active ingredient Spinosad (SPIN). Despite the efforts of regulatory agencies, there still is a lack of information regarding short- and long-term exposures to soil-dwellers, as well as effects at environmentally relevant concentrations. This work aimed to evaluate the effects of SPIT® and SPIN, on the oligochaete Eisenia fetida, and the arthropod Folsomia candida. For this, natural soil was spiked with environmentally relevant concentrations (0.00-1.49 mg of the active ingredient·kg-1 of dry soil) to assess avoidance behaviour in E. fetida and reproduction effects on both species. Further, in E. fetida adults exposed for 2- and 28-day biomarkers of oxidative stress, energetic reserves, neurotoxicity and genotoxicity were evaluated. A significant reduction in juvenile production for F. candida was observed for SPIT® at ≥0.66 mg kg-1 and SPIN at ≥0.13 mg kg-1, and although no effect was observed on E. fetida reproduction, the oligochaeta revealed a tendency to avoid soil spiked with SPIT® at 0.44, 0.66 and 1.49 mg kg-1. The sub-individual responses of E. fetida demonstrate genotoxicity upon exposure to SPIT® and SPIN for 2 days. The 2-day exposures of SPIT® and SPIN seem to induce defence mechanisms, and in general, SPIN exerted higher effects than SPIT® on the oligochaetes. Overall, the pro-oxidant performance and energy metabolism pathways were disrupted in both exposures to SPIT® and SPIN. The results suggest that spinosyns-based products can have an impact on soil arthropods F. candida and oligochaete's health, possibly affecting their essential functions in terrestrial ecosystems.

Keywords: Acute/chronic; Behaviour; Cellular alterations; Eisenia fetida; Folsomia candida; Spinosad and Spintor.

MeSH terms

  • Animals
  • Arthropods / drug effects
  • Drug Combinations*
  • Insecticides* / toxicity
  • Macrolides* / toxicity
  • Oligochaeta* / drug effects
  • Oxidative Stress / drug effects
  • Reproduction / drug effects
  • Soil / chemistry
  • Soil Pollutants* / toxicity

Substances

  • spinosad
  • Macrolides
  • Soil Pollutants
  • Drug Combinations
  • Insecticides
  • Soil