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Cadmium bioaccumulation dynamics during amphibian development and metamorphosis
Chantal Lanctôt1, Paul Callaghan2, Tom Cresswell2
1Australian Rivers Institute, and School of Environment and Science, Griffith University, Gold Coast, QLD 4222, Australia.
Journal of Hazardous Materials
|June 4, 2024
Summary
This study shows that tadpoles exposed to cadmium during metamorphosis retain less of the toxic metal than earlier larval stages. Cadmium accumulation shifts from the gut to skin and gills as tadpoles transform.
Area of Science:
- Environmental toxicology
- Aquatic ecology
- Developmental biology
Background:
- Cadmium (Cd) is a toxic heavy metal posing risks to aquatic ecosystems.
- Bioaccumulation and toxicity of cadmium are significant concerns.
- Understanding cadmium dynamics during amphibian metamorphosis is crucial for risk assessment.
Purpose of the Study:
- To investigate cadmium uptake, accumulation, and distribution in anurans during development.
- To provide insights into cadmium fate during metamorphosis.
- To compare the susceptibility of different life stages to cadmium accumulation.
Main Methods:
- Exposure of tadpoles to dissolved 109-cadmium at various developmental stages.
- Depuration in clean water.
- Analysis of whole-body and tissue cadmium concentrations using gamma spectroscopy.
- Visualization of anatomical cadmium distribution using autoradiography.
Main Results:
- Animals exposed during metamorphic climax retained significantly less cadmium than those exposed throughout larval stages.
- Cadmium partitioned primarily in skin, gills, and tail remnants in metamorphs.
- Larvae accumulated cadmium predominantly through the gut, indicating a shift in uptake routes during climax.
- Cadmium redistributed to developing tissues (e.g., forelimbs) and the regressing tail.
Conclusions:
- Metamorphosis significantly alters cadmium accumulation and distribution patterns in anurans.
- The primary route of cadmium uptake shifts during metamorphic climax.
- Stage-specific assessments are necessary for evaluating cadmium exposure risks in aquatic environments.
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