The question of how excreted pharamaceuticals persist in the environment - and what their long-term effects might be - has only tentatively been addressed by the EPA and the FDA. Unfortunately, requirements for assessing the environmental risk of pharmaceuticals didn't take effect until 1998.
This article discusses the ecotoxicology of carbamazepine, an environmentally persistent drug prescribed for a variety of illnesses, including epilepsy:
In the late 1990s, scientists began detecting carbamazepine in our waterways, and they later found that the drug resists degradation in drinking-water treatment plants.Most readers will recall that we have a similar problem with Prozac (how could you forget the media's wonderfully clever gags about depressed fish?).
Anyway, the present article notes that apart from the inherent difficulties of investigating the ecotoxicology of pharmaceuticals, the proprietary nature of these drugs has made independent investigation impossible:
Companies submit anticipated production and sales figures to the FDA during a new drug application (NDA), but this information is then withheld from the public to protect the company from competitors. This makes it impossible to determine how much of any pharmaceutical is pouring into waterways.That's not very reassuring. But here's the part of all this that I find really disturbing:
[U]nder current regulations, a company can obtain a "categorical exclusion" and not have to perform an environmental assessment if they manufacture less than 40,000 kilograms (kg) per year....A categorical exclusion does not take into account the input from multiple companies that might all be making the same drug. For instance, if 10 companies are manufacturing a drug at 30,000 kg each, for a total of 300,000 kg, there is no trigger to perform an environmental assessment.The problems with this approach are obvious enough that I'll restrict myself to a general point. Elsewhere, I've prattled about the difference between science as a field - using "field" in Pierre Bourdieu's sense of a competitive system of social relations based on power, which must be assessed in terms of its subjection to the political field - and Science as a Platonic ideal of objective, noble, honest truth-seeking. Our arbitrary, inadequate, scientifically incoherent approach to assessing pharmaceutical pollution makes that difference particularly clear, and reaffirms my belief that public "irrationality" is much less of a threat to science - and to society - than the private "rationality" of gaining and perpetuating political and economic power.