Fighting algal blooms with chemistry

A lake from above there is a a motor boat driving through a large swirling green algal bloom

Source: © Cavan Images/Alamy Stock Photo

These harmful events are the result of a complex interplay of factors, but Bárbara Pinho talks to the researchers finding out how they form and how we can stop them

Algal blooms happen when algae grow out of control in a water body, creating massive clumps of what looks like a green sludge in the water’s surface. They’re caused by various factors, but an increase in nutrients like phosphorus and nitrogen tends to be a key reason. Some of these algae produce toxins which can then cause harm to people who swim in or even drink the water, as well as to fauna and flora. The large clumps of algae consume all of the oxygen in the water and block sunlight too, meaning most aquatic beings around a bloom are at risk.