Warnings of a 'red tide' sound like 1950s anti-Communist propaganda. But the dangers to human health posed by explosions of tiny marine plants that bear this name are very real. Fuelled by sunlight and nutrient-rich waters, rapidly multiplying algae can leave swathes of open water the colour of blood. Added to environmental damage, the powerful poisons produced by red tides present serious health risks, such as respiratory problems and food poisoning. They can end up on your plate via contaminated seafood and can even kill inquisitive people who stray too close to the water. Although these events occur naturally, warmer oceans may be partly responsible for the increasing frequency of these events. Climate modelling predicts that harmful algal blooms off the northern European and East Asian coasts are set to get even worse by 2100.
Written by Jan Piotrowski
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