The presence of pharma in our water supplies is a huge problem. None of the U.S. clean water rules address this. We don't even really know the extent of the problem, because there is no testing regime. Here on the upper Potomac my town dumps all sorts of pharma and endocrine disruptors into the water that communities downstream drink from. Our town considered improving our wastewater treatment but because of the cost, won't stop until the law requires it.
Let me give some more information on that: It is true that pharmaceuticals, personal care products and endocrine disruptors are not really addressed by clean water rules, but that doesn’t mean that they are ignored. The reason that they aren’t regulated is, to quote EPA: “To date, scientists have found no evidence of adverse human health effects from PPCPs in the environment.”
Of course there are a lot of substances in the water, their concentrations are rising and it is difficult to assess their effects on humans. However, there is also a lot of dilution in the water system and the concentrations found in drinking water are still far from the concentrations where we would expect any adverse effects on human health. In fact, one of the reasons that PPCPs have become an issue is that improved measurement technologies make it possible to detect them at the small concentrations (some parts per trillion) that they are at.
Some PPCPs have now entered the EPA contaminant candidate list (CCL), which means that they are evaluated in more detail and a maximum contaminant level (MCL) might be enforced in the future. The issue is not as simple as adding more regulation, doing a bit more treatment and be safe. There are hundreds of different substances and most of them are difficult to remove. The most effective treatment method, reverse osmosis, is extremely energy intensive and thus very expensive. It is also important to know that “removal” doesn’t mean that we pick the molecules out of the water and disassemble them into their atoms, it usually means that we transfer them from one medium into another. They still have to go somewhere and likely they still end up in the environment.
So, to sum it up: PPCPs are found in water at low concentrations which are a problem for aquatic life and this problem cannot be solved easily. There is not a lot of evidence pointing to human health problems at the moment, so expensive, somewhat effective treatment methods aren’t enforced at the moment. The problem is not ignored however, the EPA regularly reevaluates the issue and research is being done on possible health effects.
The impact on aquatic life and on humans can’t be compared directly. First of all, toxicity is often related to body mass, i.e. the lethal dose is approximately proportional to the weight. This means, that a lot more of a substance is needed to have the same effect on a human than for a tiny fish. Second, and perhaps more importantly, aquatic animals are immersed in water and they are so from the very beginning. While we drink for water intake, fish “breathe water”, i.e. they constantly have water flowing into and out of their body. This makes them more susceptible to contaminants in water.
