TOXIC EFFECTS OF COPPER (CU) ON FRESHWATER PLANARIA (DUGESIA TIGRINA) REGENERATION

摘要

Industrialization and economic development have resulted in copper (Cu) contamination of aquatic environments, resulting in a variety of negative impacts that are still challenging to assess. Invertebrates usually serve as a good model to assess heavy metal toxicity in the natural environment. The freshwater planarian Dugesia tigrina is one of the macrobenthic species recognized as important organisms in toxicological studies. Its sensitivity to harmful substances and environmental stressors can be easily evaluated based on its growth, development and unique features such as its regeneration capability endpoints. In this study, the lethal and sub-lethal toxicity of copper to D. tigrina was evaluated, particularly in terms of mortality, growth, and development and regeneration performance. The LC50 was 0.751 ppm for 48h exposure, while the final body length, specific growth rate, and regeneration rate were significantly disrupted by copper at a concentration of 0.009 ppm or higher. This study provides evidence that D. tigrina shows a sensitive response to copper concentrations. Copper levels of 0.009-0.15 ppm altered individuals' development and regeneration following copper exposure. This study suggests that D. tigrina serves as a good indicator for environmental assessment. In addition, its unique regeneration characteristics benefit the assessment of the long-term effects of toxic chemicals on aquatic organisms.