An article from the Korea Times discusses problems relating to drug disposal:
When asked about how they deal with such medicines, only 63 pharmacists, 15 percent of the total, said pharmaceutical companies take them back. About 16 percent said they simply dump the medicines with other garbage.Part of the problem, apparently, is that pharmaceutical companies are offering drugs in bulk, with scant regard to actual patterns of use:
Some 64 percent said they just keep the medicines and wait for decisions from pharmaceutical companies and the Korean Pharmaceutical Association (KPA). Only 1 percent answered they take the medicines to agencies that deal with medical waste.
Pharmaceutical firms sell drugs in large containers, with a canister holding 500 to 1,000 pills. If only two to three patients come to a pharmacy with prescriptions for a particular pill, the pharmacy would use only about a dozen and the remaining hundreds of pills become overdue and useless.The article goes on to say that at least one Korean river has levels of salicylic acid that are well above allowable U.S. levels. This is a breakdown product of aspirin (and other OTC drugs), and is thus of limited interest when considering the impact of prescription drugs. That said, aspirin's a perfect example of a drug that's routinely sold in bulk containers at "bargain" prices, making it much more likely that consumers won't use it before it expires. (The United States alone produces about 300 aspirin tablets per year for every man, woman, and child in the country.)
It's often claimed that drugs break down quickly in the environment. The problem is, when drugs are constantly in use, they can be replaced as soon as they break down, which may give rise to pseudo-persistence. And while I don't know anything about the testing protocol in Korea, I do know that in the United States, we have a tendency to measure drug levels in water (sort of), while downplaying the presence of less soluble compounds in sludges.
The EPA explains the problems with assessing the ecotoxicity of prescription and OTC drugs:
"Abnormal" behavior can masquerade as seemingly normal deviation within a natural statistical variation. Change can occur so slowly that it appears to result from natural events – with no reason to presume artificial causation. Connections of cause and effect are difficult to draw, in part because of the ambiguous and subjective nature of the effects, but especially when they are convoluted as aggregations of numerous, unrelated interactions.So much for "informed choice." Speaking of which, Echidne eloquently makes a similar point in her obituary for John Kenneth Galbraith:
[M]athematics is not a religion and the knowledge we get by applying formal modeling is not superior just because it is based on formal modeling. It may be easier to follow and to criticize than a verbal explanation of a phenomenon, largely because the "words" in mathematics have very precise definitions and the "grammar" of the functions is known to all in the fields. But what the "sentences and paragraphs" say still depends on what we assumed at the beginning and on how good our data are, not just on how eloquent the mathematical language might be that we use.
Galbraith understood this. He was looking at features of the economic markets which did not lend themselves to easy mathematical expressions, and not because of faulty or unimportant reasoning, but because the required mathematics did not exist in some obvious form. Galbraith wanted to look at the complicated reality, the big picture, if you like, and the tools to do this were (and still are) limited to thinking and the use of ordinary language.