Ecotoxicity Assessment of α-Amino Acid-Derived Polyamidoamines Using Zebrafish as a Vertebrate Model

Area of Science:

• Environmental Science
• Toxicology
• Polymer Chemistry

Background:

• Polyamidoamines (PAAs) derived from α-amino acids are effective flame retardants for cotton.
• These water-soluble, amphoteric polyelectrolytes possess a predominantly negative charge.
• Assessing the aquatic ecotoxicity of these materials is crucial for their environmental application.

Purpose of the Study:

• To evaluate the aquatic ecotoxicity of three α-amino acid-derived polyamidoamines (PAAs).
• To determine the impact of PAAs on zebrafish embryo survival, hatching, and morphology.
• To investigate the effects of PAAs on zebrafish sensory-motor responses.

Main Methods:

• Fish embryo acute toxicity tests were conducted on zebrafish embryos using PAA concentrations ranging from 1.5 to 500 mg L⁻¹.
• Transgenic zebrafish lines were used to assess microscopic vascular and musculoskeletal defects.
• Sensory-motor tests, including response to light/dark cycles and tactile stimuli, were performed.

Main Results:

• No statistically significant differences in toxicity were observed compared to the control group across all tested concentrations.
• Survival rates remained above 90%, hatching rates above 80%, and morphological defects were comparable to controls.
• Mild effects on the neuromotor system were noted at concentrations above 10 mg L⁻¹, with a cystine/glycine copolymer showing the greatest impact.

Conclusions:

• The studied polyamidoamines exhibit minimal impact on aquatic systems.
• PAAs demonstrate potential as ecofriendly materials for various applications.
• Further consideration of these PAAs for sustainable applications is warranted based on their low ecotoxicity.