Hormesis and stage specific toxicity induced by cadmium in an insect model, the queen blowfly, Phormia regina Meig

• Published in: Environmental pollution (1987) 2003-01, Vol.124 (2), p.257-262
• Main Authors: Nascarella, Marc A., Stoffolano, John G., Stanek, Edward J., Kostecki, Paul T., Calabrese, Edward J.
• Format: Article
• Language: English
• Subjects: Animal, plant and microbial ecology; Animals; Applied ecology; Biological and medical sciences; Blowfly; Cadmium; Cadmium - toxicity; Diptera - drug effects; Dose-Response Relationship, Drug; Dose–response; Ecotoxicology, biological effects of pollution; Effects of pollution and side effects of pesticides on protozoa and invertebrates; Environmental Pollutants - toxicity; Fundamental and applied biological sciences. Psychology; Hormesis; Larva - drug effects; Metamorphosis, Biological - drug effects; Models, Biological; Pupa; Stage-specific
• ISSN: 0269-7491; 1873-6424
• DOI: 10.1016/S0269-7491(02)00479-7

This is the first report of a heavy metal displaying a hormetic-like biphasic response for early developmental success, while at the same time displaying stage-specific toxicity at a later developmental stage. Hormesis is an adaptive response, commonly characterized by a biphasic dose–response that can be either directly induced, or the result of compensatory biological processes following an initial disruption in homeostasis [Calabrese and Baldwin, Hum. Exp. Toxicol., 21 (2002), 91]. Low and environmentally relevant levels of dietary cadmium significantly enhanced the pupation rate of blowfly larvae, while higher doses inhibited pupation success. However, dietary cadmium at all exposure levels adversely affected the emergence of the adult fly from the pupal case. Such findings represent the first report of a heavy metal displaying a hormetic-like biphasic response for pupation success, while at the same time displaying stage-specific toxicity at a later developmental period. These conclusions are based on substantial experimentation of over 1750 blowflies, in seven replicate experiments, involving 10 concentrations per experiment. These findings indicate the need to assess the impact of environmental stressors over a broad range of potential exposures as well as throughout the entire life cycle.