Domoic Acid Toxicity in Marine Ecosystems

Domoic acid is a neuroexcitatory amino acid produced primarily by diatoms of the genus Pseudo-nitzschia and certain red algae. Under conditions of elevated temperature, nutrient enrichment and altered ocean circulation, these organisms can form harmful algal blooms (HABs) that release domoic acid into the water column. Once in the environment, the toxin is taken up by filter-feeding bivalves, small pelagic fish and cephalopods, and is then biomagnified through successive trophic levels. Marine mammals, seabirds and coastal communities that consume contaminated seafood may experience acute amnesic shellfish poisoning, characterised by gastrointestinal distress, seizures and memory impairment. Sublethal exposures have been linked to chronic neurological and reproductive disorders in wildlife, while regulatory monitoring of shellfish beds has reduced human incidents in many regions. Nevertheless, climate-driven shifts in bloom frequency, combined with gaps in our understanding of low-dose and developmental toxicity, underscore the need for continued ecological surveillance and mechanistic research. The global distribution of Pseudo-nitzschia species and the mobility of commercial fisheries elevate domoic acid toxicity to an issue of international concern, with implications for marine conservation, food security and public health policy.

Research from Nature Portfolio

Structural and biosynthetic studies of domoic acid precursors have revealed six novel related compounds in the red alga Chondria armata, including linear glutamate-derived intermediates and cyclised isodomoic acids. Detailed elucidation of side-chain modifications has clarified the late steps in toxin assembly, demonstrating that geranyl-glutamate conjugates serve as genuine biosynthetic precursors in diatoms. These insights provide a foundation for genetic or chemical strategies to disrupt toxin production at its source.

Domoic Acid Toxicity in Marine Ecosystems publication trend

The graph below shows the total number of articles in domoic acid toxicity in marine ecosystems across all publications each year (not limited to Nature Index journals).

Technical terms

Harmful algal bloom (HAB): A rapid proliferation of toxin-producing phytoplankton that can disrupt ecosystem function and food webs.

Biomagnification: The progressive concentration of a substance in the tissues of organisms at higher trophic levels.

Amnesic shellfish poisoning (ASP): A human and wildlife illness marked by gastrointestinal and neurological symptoms, including memory loss, following domoic acid ingestion.

Glutamate receptor: A membrane protein in nervous tissue that mediates excitatory neurotransmission and is overactivated by domoic acid.

One Health approach: A multidisciplinary framework linking environmental, animal and human health to address shared challenges.

References

1. Domoic Acid: A Review of Its Cytogenotoxicity Within the One Health Approach. Antioxidants (2024).
2. EU Regulatory Risk Management of Marine Biotoxins in the Marine Bivalve Mollusc Food-Chain. Toxins (2018).
3. Domoic Acid Toxicologic Pathology: A Review. Marine Drugs (2008).
4. Domoic Acid Epileptic Disease. Marine Drugs (2014).
5. Cephalopods as Vectors of Harmful Algal Bloom Toxins in Marine Food Webs. Marine Drugs (2013).
6. Six domoic acid related compounds from the red alga, Chondria armata, and domoic acid biosynthesis by the diatom, Pseudo-nitzschia multiseries. Scientific Reports (2018).