That seems unlikely, given that one of the experiments with a positive result was conducted in a remote area ofChina while another that had a negative result took place in Belgium, one of the most crowded partsof the planet.
Artemisia grows like a weed across China and South-East Asia, but the best plants are found only in certain partsofChina, such as Guangxi and Hunan, which produce mostof the world's supply, and in Vietnam.