Carbon-14 shifts through the food chain, affecting fish brain chemistry and metabolism
image: On the left, identified organically bounded C-14 (OBC-14, red dots) in metabolites of zebrafish brain were labeled in the KEGG global pathway map. The blending of C-14 induced significant effects such as reducing global DNA 5mC methylation level and swimming velocity of fish via alleviating the metabolic reaction kinetic, as shown on the right.
Credit: ©Science China Press
In a new research paper featured in the National Science Review, scientists have discovered how carbon-14 (C-14), a radioactive isotope, shifts through the food chain from algae to zebrafish, leading to significant changes within fish brains. This study was led by Prof Liang Mao’s group at Nanjing University in China, who explored the implications of C-14 on living organisms beyond its known radiological impacts.
The team established an experimental food chain involving algae, water fleas and zebrafish. They found that when algae absorb inorganic C-14, it quickly transforms into organically bound C-14, which then becomes part of the zebrafish’s biomolecules after being consumed by water fleas and subsequently by the fish. Notably, the C-14 accumulates persistently in the brain tissue of zebrafish, influencing DNA methylation patterns and causing neuropathological changes.
Furthermore, global isotope tracing metabolomics uncovered that C-14 exposure involves various critical metabolic pathways in zebrafish, including one-carbon metabolism and nucleotide metabolism. These findings suggest that even low levels of radiotoxic nuclides like C-14 can pose health risks through chemical effects such as the isotope effect, affecting metabolic processes and potentially leading to long-term health issues.
This research provides a deeper understanding of the environmental impact of C-14 released from nuclear industries and highlights the need for more stringent measures to protect public health from potential threats posed by radionuclides in the biosphere.