Padma Venkatraman, Ph.D., one of the studys lead authors, presented estimates of probable environmental concentrations (PECs) of the top 200 drugs to scientists gathered here for the 223rd national meeting of the American Chemical Society, the worlds largest scientific society.
Were trying to make an intelligent guess as to whats out there in the environment and whats probably toxic, Venkatraman said during an interview. As for any danger to people, We certainly dont have any evidence that most pharmaceuticals pose a human health risk, although the presence of carcinogens or teratogens even at low concentrations is of potential human health concern, she emphasized.
Any danger from the drug concentrations is more likely to be to aquatic organisms than humans, according to Venkatraman. Our research suggests that certain existing drugs may be present at levels at which they have the potential to exert sublethal effects.
The survey is based on calculated total drug sales and prescriptions and a search of the medical literature, said Venkatraman. Based on the existing data about the drugs biochemistry and existing data on its metabolism, we came up with the estimates.
Because some drugs are not metabolized before elimination, the researchers calculated PECs with and without metabolism, Venkatraman noted. Also, there is the fact that expired medications are often flushed down the toilet, she added.
Although the survey focused primarily on prescription drugs, some over-the-counter drugs, such as ibuprofen, were included, Venkatraman said.
Although Venkatraman would not