Potentially, toxic "natural" herbal remedies are the "health" rage illustrating how social forces make categories impervious to deconstruction regardless of their incongruence. Naturally, a politics of possibility requires transcending such categories..

My neighbor recently had the unfortunate experience of being jettisoned from his bicycle into the back of a car. The incident resulted in a painful blow to the neck followed by a Good Samaritan rushing to his aid with an offer of herbs which she "takes all the time for pain." With the explosion of homeopathy, the slightest sniffle or cough can result in an offer of a specialized supplement followed by an herbalist's statement that it is "natural."
There is every reason to believe that certain indigenous chemical products found in plants, animals or the earth can be therapeutic. In fact, many conventional medicines are purified forms of naturally occurring compounds. There are also indirect reasons to believe in the historical effectiveness of herbal remedies. Consider tea, regardless of the effect from leaves, the routine heating of water prior to consumption serves to kill pathogens contributing to health and longevity.
Evidence abounds of nature's more ominous side. Wild mushrooms and water hemlock are frequently mistaken for edible varieties and the results can be lethal. Woolf provides an excellent review of the toxicity of herbal products, particularly for pregnant women and children. California has added ingredients in herbal remedies to its list of compounds known to cause cancer. In addition to the toxicity of indigenous chemicals, studies demonstrate contamination of commercial products with lead, arsenic, mercury and other pollutants.
Thanks to aggressive lobbying, herbal remedies do not receive the same regulatory scrutiny as conventional medicines, resulting in a "don't-ask-don't-tell" policy regarding safety. Further, there is also the odd propensity for the firmest believers in homeopathy to decry modern medicine - observation bias, perhaps, where they are only reading safety reports about the "conventional" products that are actually being screened.
The point here is to neither condemn nor promote a particular approach to life, health and happiness. Rather, it is to illustrate how various social forces may combine to make certain categories impervious to deconstruction and enable them to maintain mythical holds regardless of how incongruous they become. The politics of possibility requires transcending such sectarian categories. That is a natural fact.