As countries fail to adopt a treaty to throttle plastic pollution globally, the story of Eastern Cape herders tackling the scourge of throwaway nappies in communal grazing unwittingly exposes a new form of pollution sweeping in across the region. Airborne microplastics may be to a critical SADC water factory what acid rain was to Europe and North America in the 1980s.

As countries fail to adopt a treaty to throttle plastic pollution globally, the story of Eastern Cape herders tackling the scourge of throwaway nappies in communal grazing unwittingly exposes a new form of pollution sweeping in across the region. Airborne microplastics may be to a critical SADC water factory what acid rain was to Europe and North America in the 1980s.

Watching Tukulo Mtshayelo amble through the veld, it seems he'd rather spend his Fridays cleaning up the 'hood instead of cruising a shopping mall like many his age. The lanky 25-year-old -- "TK" to most -- crunches through ankle-high grass left crisp as parchment by autumn's cooler mood.

Mtshayelo makes his way through the outskirts of his village -- about an hour's drive from Matatiele in the Eastern Cape -- to visit a spring, one of three natural sources that they draw on for home use and to water their livestock.

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The object of his pride: a brick-and-cement structure that the community sank into the stream bed a few metres downhill from the spring's eye. Now it's protected from the cattle's trampling hooves or villagers hauling their water containers in and out of the collection point. Instead, people can...