Is Johannesburg the most radioactive city in the world? – by Naledi Mashishi (Afica – February 15, 2021)

South African advocacy groups have claimed Johannesburg is the most radioactive city on Earth, because of the mining of uranium-rich gold fields. But uranium contamination and radioactivity aren’t the same thing.

The history of gold mining and the South African city of Johannesburg are intimately linked – the city was founded after the discovery of the precious metal on the Witwatersrand in 1884. Locals call it “the City of Gold”, but can it also claim the title of “most radioactive city on earth”?

“Joburg is the most radioactive city on the planet, thanks to its gold-mining past, says Earthlife Africa,” read an article on news website Independent Online in late 2020. It linked this startling claim to the dumping of uranium as a waste product of gold mining.

The claim has also been attributed to the Bench Marks Foundation, an independent organisation monitoring corporate performance, by news channel eNCA. (Note: Neither Earthlife Africa or the Bench Marks Foundation answered questions about the source of the statistic.)

The country’s mining industry has long been criticised for its environmental and social impact. Johannesburg’s mine dumps have also been flagged by environmental researchers for high levels of the mineral uranium.

But is Johannesburg the most radioactive city on the planet? We checked. According to the US Environmental Protection Agency (EPA), radiation is energy that travels from its source in energy waves or energised particles. There are two types of radiation: non-ionising radiation and ionising radiation.

For the rest of this article: