A hidden artefact: how surfactants can distort the results of springtail reproduction tests

Jonas Fischer ¹, Borbála Szabó ¹, Leonid Manikhin ¹

⁰University of Bremen, UFT, General and Theoretical Ecology, Bremen, Germany.

Environmental Toxicology and Chemistry +

|

February 25, 2025

View abstract on PubMed

Summary

Surfactants like Break-Thru® S 301 can interfere with soil invertebrate testing, causing false negatives in reproduction tests. Heat extraction is a more reliable method than flotation for assessing surfactant toxicity in springtails.

Area Of Science

Environmental Toxicology
Soil Ecotoxicology
Invertebrate Biology

Background

Surfactants are common soil contaminants, impacting soil health.
The standard springtail reproduction test (OECD guideline 232) is used to assess chemical toxicity.
Break-Thru® S 301 is a trisiloxane surfactant used in firefighting liquids and pesticide mixtures.

Purpose Of The Study

To evaluate the effects of Break-Thru® S 301 on the reproduction of Folsomia candida.
To compare juvenile extraction methods (heat vs. flotation) for accuracy in surfactant toxicity testing.
To assess the impact of Break-Thru® S 301 on reproduction investment and hatching success.

Main Methods

Testing the effects of Break-Thru® S 301 on Folsomia candida reproduction in three soil types.
Employing both heat extraction and flotation methods for juvenile recovery.
Measuring reproduction investment and hatching success as additional endpoints.

Main Results

Flotation method showed a significant decline in recovered springtails at 2 mg/kg Break-Thru® S 301 in sandy soils.
Heat extraction method revealed no significant effects at the same concentrations.
Reproduction investment and hatching success showed no toxicity indication for Break-Thru® S 301.

Conclusions

Break-Thru® S 301 artificially reduced water surface tension during flotation, causing juveniles to sink, leading to false negatives.
The flotation method in OECD guideline 232 is susceptible to artefacts when testing surfactants.
Recommendations include pre-testing surfactant effects on flotation or using heat extraction, with suggested guideline revisions for accurate chemical risk assessment.

Keywords:

Organisation for Economic Co-operation and Development (OECD) guideline 232 reproduction test springtail surfactants