Chinese herbal remedy 'causes record high rate of urinary cancer in Taiwan'
10:28 GMT, 12 April 2012
A banned substance still found in some Chinese herbal remedies sold illegally in the UK and U.S has been blamed for the high rate of urinary tract cancers in Taiwan.
Found in Aristolochia plants, Aristolochic acid (AA) is an ingredient common in botanical Asian remedies for aiding weight loss, easing joint pain and improving stomach ailments.
Aristolochic acid has been banned in the UK and U.S but there have been recent cases of it being sold in Chinese herbal shops
However, U.S researchers said the toxic ingredient is a potent human carcinogen that has been linked to more than half of the UTC cases in Taiwan. It is also known to trigger kidney failure.
In Taiwan, where previous research has shown about one-third of the population has taken AA in recent years, rates of urinary tract and kidney cancer are about four times higher than in Western countries where use is less common, said the findings in the Proceedings of the National Academy of Sciences.
'It is a rare tumor and Taiwan has the highest incidence of any country in the world,' said lead author Arthur Grollman from Stony Brook University in New York.
'The fact that Taiwan had the highest incidence both of cancer and this renal disease – that was our clue that something was going on there,' he added to AFP.
The research was based on 151 patients with urinary tract cancer, of whom 60 percent showed specific mutations linked to the herbal remedy.
In particular, after being ingested the acid forms a unique kind of lesion in the renal cortex, and also gives rise to a particular mutational signature in the TP53 tumor suppressing gene, said the study.
Signs of harm have emerged in recent decades. In the 1990s, a group of Belgian women reported sudden late stage kidney failure after taking a weight loss drug that contained AA.
The ingredient has been banned in the U.S and UK however it is difficult to control as it is available via the internet.
In 2010, a civil servant told a court in Chelmsford, Essex, that she suffered kidney failure and urinary tract cancer after taking an acne supplement that contained AA.
She took it between 1997 and 2002. The substance was banned in the UK in 1999.