Sensitivity of amphibian embryos and tadpoles to Mimic® 240 LV insecticide following single or double exposures

Abstract

Abstract-Mimic 240 LV is a novel, narrow-spectrum insecticide containing the active ingredient tebufenozide. Tebufenozide mimics the action of the insect molting hormone ecdysone and shows specific activity toward larval Lepidoptera. In Canada, Mimic 240 LV has been proposed for use in forest pest control, whereas a different formulation has been registered for use in agriculture. We examined the effects of single and double pulses of Mimic 240 LV (tebufenozide) on the development, growth, and predator avoidance behavior of four frog species (wood frogs Rana sylvatica, leopard frogs R. pipiens, green frogs R. clamitans, and bullfrogs R. catesbeiana) exposed in the laboratory as embryos or tadpoles. Nominal doses ranged from 3.0 mg/L to 9.0 mg/L tebufenozide, and exposures were terminated at 96 h following single, or 192 h following double, exposures. More than 90% of the animals exposed as embryos hatched. Embryos exposed late in development and subsequently hatching into tebufenozide-contaminated water all hatched and responded normally. Tadpole growth was not delayed following exposure, and premetamorphic green frogs successfully completed metamorphosis following exposure to the highest concentration. The results suggest that Mimic 240 LV, when used at the suggested application rates, will not severely affect the aquatic stages of ranid amphibians.

Uptake, Metabolism, and Effects on Detoxication Enzymes of Isoproturon in Spawn and Tadpoles of Amphibians

“…This insu$cient physical barrier of protection is reported for other pesticides for amphibians and "sh (Hashimoto et al, 1982;Wiegand et al, 2000). In contrast, Berrill et al (1998) and Pauli et al (1999) reported that for amphibians the jelly coat surrounding the embryo provided a protective layer during growth and development. The protection of the forming embryo from pesticide contamination appears to be strongly dependent on tested species and investigated pesticides.…”

“…Therefore, amphibians of these stage with complete operculum were used in exposure investigations. Pauli et al (1999) con"rmed that tadpoles at…”

“…Berrill et al (1995) found that within each tested ranid species, 1-and 8-day-old tadpoles are equally sensitive to treatment with the insecticide fenitrothion. However, Pauli et al (1999) described that di!erent aquatic stages of four investigated ranid amphibians exhibited di!ering degrees of sensitivity to the tested insecticide tebufenozide. Susceptibility of di!erent developmental stages of amphibian tadpoles to pesticide contamination appears to be strongly dependent on both the species and the chemicals tested.…”

Efeitos de pesticidas sobre a fragilidade osmótica de eritrócitos – Uma breve revisão

“…Alguns praguicidas e seus metabólitos têm sido encontrados como poluentes no fundo e superfície de águas, no solo (Kolpin et al, 2004;Fava et al, 2005;Worrall e Besien, 2005), e na atmosfera (Dubus et al, 2000;Duyzer, 2003) e são prováveis responsáveis pela perda da biodiversidade e a deterioração de habitats naturais (Pauli et al, 1999). O aumento da consciência dos riscos relacionados ao uso intensivo de praguicidas tem levado a uma atitude mais crítica pela sociedade agrícola, gerando mudanças concernentes ao uso para evitar danos ambientais e gerar maior segurança alimentar (Saba e Messina, 2003).…”

Effects of Roundup® Pesticide on the Stability of Human Erythrocyte Membranes and Micronuclei Frequency in Bone Marrow Cells of Swiss Mice

“…Some pesticides and their metabolites have been considered as pollutants of the bottom and surface of waters, soil [1][2][3] and atmosphere [4]. They are likely responsible for the loss of biodiversity and deterioration of natural habitats [5]. Increased awareness on the risks related to the intensive use of pesticides has led to a more critical attitude by the agricultural society to prevent future environmental damage [6].…”