This is something that you wouldn't expect: not dust, nor salt or sand, but foam is blowing through the streets of Bangalore, India.
When sewage gets into the lake, nutrients, in the form of nitrogen and phosphorus, go in too. The nitrogen is taken by the plants in the water, while the phosphorus gets trapped in the sediment. The pre-monsoon rainfall and the high wind velocity churn the lakes, and the phosphorus that is trapped in the sediment is released, creating the foam.
The toxic foam can cause skin rashes and respiratory problems. It could
become a major health issue in the future because long-term exposure to
phosphate can lead to kidney problems, known as Chronic Kidney Disease
of non-Traditional causes otherwise known as Phosphate Fertilizer Related Chronic Kidney Disease.
This isn’t the first time the city has experienced this problem —social
media posts documenting the phenomenon date back to 2013. According to
the Times of India, foaming has been a problem on two other lakes in the area, namely Lake Bellandur and Lake Subramanyapura. But the problem is occurring in the whole of India: Ramakrishnapuram Lake (Puram Lake) near Neredmet is also 'frothy'. Groundwater is fed by the lake and you can understand what happened next.
No other official action, besides testing for chemicals in the lakes, has been taken, according to news reports. So it looks like the toxic foam will continue to plague the streets.