Kyiv predicts 42,000 at risk from dam flooding | First Thing

US National Security Council says burst dam has probably caused many deaths' as fears grow for missing people. Plus, scientists trace the origins of masturbation

Good morning.

About 42,000 people are at risk from flooding on both sides of the Dnipro River after the destruction of the Nova Kakhovka dam, Ukrainian officials have said, with flood waters expected to peak on Wednesday.

How are the relief efforts going? Relief workers on the Ukraine-controlled right bank of the river have reported having to operate under fire. The biggest difficulty right now is not the water. It's the Russians on the other side of the river who are shelling us now with artillery," said Andrew Negrych, who was coordinating relief efforts yesterday for a US charity, Global Empowerment Mission.

What has Volodymyr Zelenskiy said? The Ukrainian president has used his social media channels to issue another statement about the destruction of the dam, claiming that hundreds of thousands of people have been left without access to drinking water. He said: Russian terrorists have once again proved that they are a threat to everything living. The destruction of one of the largest water reservoirs in Ukraine is absolutely deliberate."

What's the biggest concern? Air-quality alerts are triggered by a number of factors, including the detection of fine-particle pollution - known as PM 2.5" - which can irritate the lungs. We have defenses in our upper airway to trap larger particles and prevent them from getting down into the lungs. These are sort of the right size to get past those defenses," said Dr David Hill of the American Lung Association's national board of directors. When those particles get down into the respiratory space, they cause the body to have an inflammatory reaction to them."