Common toxins in the ocean will become even more toxic in the future, threatening marine life and even humans, new research reveals.
Two of these toxins - saxitoxin and tetrodotoxin - are used by a variety of species, for example puffer fish or blue-ringed octopuses, to attract mates, ward off predators and kill prey.
The research is published today in Nature Climate Change.
Saxitoxin is also released in high concentrations into the marine environment during harmful algal blooms, from where it can accumulate in the marine food chain, for example in shellfish.
Consuming such shellfish can cause a condition called “paralytic shellfish poisoning”, which may be fatal to humans.
An international team of experts led by the University of Hull has discovered that ocean acidification will cause these toxins to become up to 35% more toxic.
Christina Roggatz, lead author from the Energy and Environment Institute at the University of Hull, says: “This research reveals a new dimension of climate change effects. We calculated the toxicity of these two key molecules in both, current and end-of-the-century conditions, using the latest IPCC predictions for future pH levels and ocean temperatures. We found a substantial increase of their toxic forms.”
Whilst harmful algae will benefit from these increased levels of toxicity, most marine life will be negatively affected.
Working with scientists at the University of Hull were researchers from the University of Nottingham and the South Slough National Estuarine Research Reserve and the Knik Tribe in the U.S.