Toxicity effects and biomarkers of tebufenozide exposure in Yuukianura szeptyckii (Collembola: Neanuridae)

Abstract

Tebufenozide is an insect growth regulator used to control pest caterpillar populations. As an ecdysone agonist, tebufenozide is equally toxic to several non-target arthropod species, binding the receptor sites of the molting hormone 20-hydroxyecdysone and causing premature and lethal molting. In this study, the toxic effects of tebufenozide were assessed, and biomarkers of tebufenozide exposure were identified, in the non-target soil collembolan species Yuukianura szeptyckii. Adult mortality and reproduction in Y. szeptyckii exposed to tebufenozide were evaluated after 28 days of exposure and were used to calculate LC and EC, respectively. The LC could not be determined, because the mortality values observed were below 50%, even when exposed to the highest concentration tested (700 mg/kg), but the EC was 95.5 mg/kg. Effects on hatching and molting rates were evaluated using compressed soils, to prevent experimental individuals from burrowing; thus, all eggs and exuviae were detectable on the soil surface. Significant negative effects of tebufenozide exposure on the hatching rate and molting frequency were observed only at the highest concentration tested (700 mg/kg). Proteomic analyses were conducted to detect the cryptic effects of toxicity in adult collembolans exposed for 28 days to 43.8 mg/kg of tebufenozide, a concentration at which no toxicity effects were observed. The production rates of two ribosomal proteins, as well as proteins involved in apoptotic cell signaling, were higher in collembolans exposed to tebufenozide than in the control group. However, the production of proteins involved in glycolysis and energy production was downregulated. Therefore, the ecotoxicoproteomic approach is a promising tool for measuring the cryptic effects of tebufenozide exposure in Y. szeptyckii at low concentrations.

Temperature and Aging Affect Glyphosate Toxicity and Fatty Acid Composition in Allonychiurus kimi (Lee) (Collembola)

“…In evaluating the risks of pesticides, identifying the effects of pesticides on organisms at the sub-individual level is important because pesticides may not only affect the survival or reproduction of organisms, but also impair the ecological fitness of individuals through sublethal effects [25,26,28]. Our study using fatty acids as a biomarker confirmed that A. kimi can be biochemically affected by glyphosate treatment even at the concentrations at which no glyphosate-induced adult mortality and juvenile reproduction were observed (Figure 2 and Table 2).…”

“…Biomarker-based approaches have been extensively applied to assess these sub-individual effects [25,26]. Enzyme activity [27], protein composition [28], and gene expression [29] have been mainly used as toxicity biomarkers for soil animals. In addition to these biomarkers, fatty acids are also considered potentially important biomarkers, because they are essential components of organisms and play a critical role in energy storage, cell structure, and regulatory physiology [30].…”

Bioaccumulation and Toxicity of Organic Chemicals in Terrestrial Invertebrates

“…Proteins related to glycolysis can be affected by low doses (e.g., <NOEC for reproduction of 43.8 mg a.i. kg À1 d.w.) of tebufenozide in the collembolan Yuukianura szeptyckii [93]. Neonicotinoids can induce gene downregulation in the brain of honey bee workers, namely, those encoding the enzymes related to glycolysis and lipids.…”

“…Body weight of P. scaber was not affected by chlorantraniliprole [104], but it was significantly lower in the presence of thiacloprid [105]. The molting frequency of Y. szeptyckii was affected by tebufenozide [93]. Yu et al [114] reported no effects of imidacloprid on the development time, pupation, and adult emergence of the ladybug Coccinella septempunctata, while egg production and hatching were compromised.…”

Determination, residue analysis, risk assessment and processing factors of tebufenozide in okra fruits under field conditions

“…As an ecdysone inhibitor, it has a specific insecticidal mechanism: tebufenozide mimics the function of natural insect ecdysone, interacts with the ecdysone receptor protein, induces early maturity of insects, and causes insects to moult to death. As a third‐generation insect growth regulator, tebufenozide was developed to replace traditional pesticides and to reduce environmental and food contamination . Due to its unique insecticidal mechanism and high selectivity, it is safe and reliable for the environment and non‐target organisms.…”