A growing source of the UKs blood plasma is from Mexicans crossing the border into the US and donating at high frequencies, which some experts fear could risk their health
The first time I went, I wanted to cry, said Luca, a mother of three, describing how her economic situation would compel her to do the journey from her home in the Mexican border city of Ciudad Jurez to line up outside a blood plasma donation center in El Paso, Texas.
There are more than 800 such facilities in the US and they have been expanding around the southern border in recent years, harvesting plasma of a growing number of Mexicans traveling across the border on temporary visas, in need of cash.
In a regular week, before the coronavirus outbreak, thousands of donors crossed the border into the US to make money this way, which appears to be in a legal gray area.
Some donors have given plasma twice a week for years, and scientific research has shown that high donation frequency can have harmful long-term consequences, including to the immune system.
The UK imports all of its plasma used for the production of medicine from the US. This is a legacy of 1990s fears in the UK over mad cow disease, known as Creutzfeldt-Jakob, though the UK has only recently stepped up importing plasma from the border area.
The leading supplier is BPL Plasma, whose parent company is based in the UK and which runs 51 plasma centers in the United States, including six based in the border area.
By Saturday, BPL Plasmas El Paso center located just seven blocks from the border bridges was nearly empty of signs of donors, as the Trump administration ordered the border partially closed for 30 days. But as recently as Thursday last week, NDR/the Guardian saw 21 donors waiting in line outside the center before it opened.