Pontifications on Poison
Being some ramblings on events associated with poisonous plants.
Saturday 25th June 2011
Earlier this week, when writing about alcohol and older people, I pointed out that the media would have you believe that the Royal College of Psychiatrists’ report on the subject was the first to suggest that lower limits of alcohol consumption were indicated for people over 65. It was an indication of a frequently seen phenomenon where work is published but goes unnoticed outside the immediate field of interest and only later does it come to the attention of the mainstream media and achieve wide circulation.
I believe the same thing will happen, again, but this time it is the active ingredient in plants of the Aristolochia genus, aristolochic acid, that will, at some point in the future, hit the headlines.
At the annual meeting of the American Society of Clinical Oncology (ASCO) held in Chicago from 3rd to 7th June, Professor Arthur Grollman gave what is known as a poster presentation of the latest work he and his colleagues have completed on the potential effects of aristolochic acid. It was Professor Grollman who demonstrated that the presence of Aristolochia clematitis in wheat fields in the Balkans was the cause of the condition then known as Balkan endemic nephropathy (BEN), a chronic renal disease associated with complete kidney failure and cancer of the upper urinary tract.
After wrongly formulated Traditional Chinese Medicine (TCM) was found to be responsible for an outbreak of end stage renal disease and urothelial cancer in women in Belgium who had been given preparations to assist weight loss, Professor Grollman began to look at the possibility of widespread poisoning in Taiwan. The Belgian incident resulted from confusion between Aristolochia fangchi and Stephania tetrandra. In Chinese, Aristolochia fangchi is known as ‘Guang Fang ji’ and Stephania tetrandra is ‘Han Fang ji’ and the two have some limited physical similarities. The question was whether use of the wrong herb was an isolated incident or whether the two plants were used interchangeably in TCM.
In earlier work, Professor Grollman had established that poisoning by aristolochic acid results in DNA changes that can be seen years after the poisoning incident and are present even if only small amounts of the poison have been ingested.
In the latest work, samples of tissue removed from 48 patients during cancer surgery were tested and the DNA changes associated with aristolochic acid were found in nearly one third. The conclusion given to the meeting is that aristolochic acid poisoning, ‘a silent, yet widespread iatrogenic disease, is an international public health problem of significant magnitude’. Because of the widespread use of CTM, it is believed that one third of the population of Taiwan may be at risk of renal disease.
The effects of aristolochic acid are cumulative and can take many years to result in disease if the dosage is low, so it is likely that lower life expectancy has prevented this problem coming to the fore. Certainly, in the Balkans, aristolochic acid nephropathy (AAN), the name now given to BEN, only became known since the 1950s.
Because the debate about TCM versus ‘Western’ medicine rapidly becomes political there does not seem to have been any investigation of the possible extent of aristolochic acid in the People’s Republic of China but, if similar products to those found in Taiwan are in use on the mainland, then many millions of people may be at risk of death from kidney failure of urinary tract cancer in the next few decades.
You would think the possibility of millions of people dying early would get a fair bit of attention from the media and, in time, I suspect it will. For now, however, the poster presentation title, "Aristolochic acid nephropathy in Taiwan" produces only 17 results in Google.