(NaturalNews) A study conducted by researchers from the U.S. Geological Survey (USGS) has exposed drug factories as major sources of pharmaceutical pollution, revealing drug concentrations in the wastewater downstream of these factories more than a thousand times higher than those found in other wastewater.
"The concentrations coming out of effluent are much higher than we would ever have thought," said lead author Patrick Phillips, whose study was published in the journal Environmental Science & Technology.
"If people are interested in keeping drugs out of the environment, this may be a source we haven't thought about before."
In recent years, pharmaceutical contamination of water supplies -- at first presumed to come primarily from human urine and feces -- has become an issue of growing concern around the world. Because the world's water systems are so interconnected, more than 100 different drugs have been detected across North America, Europe and Asia, even in wells and remote regions. Based on its own research and information from water providers in 77 metropolitan areas and 52 small communities, the Associated Press has estimated that at least 46 million people across the United States are regularly exposed to tap water contaminated by pharmaceuticals.
Many drugs are not regulated as water pollutants, and as such no "safe" exposure limits have ever been set. But scientists are concerned that because many drugs are designed to be active in the body in concentrations even on the order of 1 part per billion (ppb), the health effects of this pollution for human and environmental health will be severe. Indeed, a recent USGS study found intersex fish at one-third of all sites tested.
"These are chemicals that are designed to have very specific effects at very low concentrations," said zoologist John Sumpter of London's Brunel University. "That's what pharmaceuticals do. So when they get out to the environment, it should not be a shock to people that they have effects."
In addition, people consume water in large quantities over the course of their entire lives, and each glass contains a completely untested mix of potentially dozens of bioactive compounds -- making the ultimate effects impossible to predict. To make matters worse, many toxic chemicals are known to build up in the tissue of humans and other animals.
For a long time, the pharmaceutical industry has insisted that strict controls prevent significant quantities of their products from entering the water supply at manufacturing plants. But in 2007, researcher Joakim Larsson of the University of Gothenburg found antibiotics in concentrations as high as 31 milligrams per liter being discharged from a waste treatment plant in India. Levels of ciproflaxin in the water were higher than the maximum safe level for human blood.
The plant in question was receiving wastewater directly from a factory manufacturing the drugs.
To see whether the same thing was occurring in the United States, Phillips and colleagues collected effluent samples leaving 26 wastewater treatment plants across the United States. Two of the plants in question were receiving wastewater from factories that assemble drugs out of their base ingredients, including one plant that received at least 20 percent of its untreated water from such factories.
Both plants receiving pharmaceutical wastewater and one of the control plants were in New York state, while the 23 other plants were in 11 other states. Between 35 and 38 effluent samples were taken from each New York plant; only one sample was taken from each other plant.
Anomalies immediately emerged in the analysis of the plants serving pharmaceutical factories.
"When we scanned the effluent samples using capillary gas chromatography/mass spectrometry, we noticed large peaks due to unknown substances," researcher Dana Kolpin said. Analysis revealed the substances to be seven widely used muscle relaxants and opiate painkillers, in concentrations often thousands of times higher than those in water coming from the 24 other plants. The seven drugs were also detected in a drinking-water reservoir 20 miles downstream of one of the treatment plants.
All seven drugs were also found at the plants not serving pharmaceutical factories, typically in concentrations less than 1 ppb. In contrast, concentrations of the anti-obesity stimulant phendimetrazine and the muscle relaxant carisoprodol were higher than 40 ppb at the plants serving drug makers. Concentrations of the barbituate butalbital reached 160 ppb, and those of the painkillers methadone and oxycodone reached 400 ppb and 1700 ppb, respectively. The highest concentrations were found for the muscle relaxant metaxalone, at 3,800 ppb. These concentrations were similar to those found in the India study, in spite of that country's supposedly laxer regulatory framework.
"I don't think anyone ever thought we'd see these concentrations in streams," Phillips said.
The study is the first in the U.S. to show that drug factories are a major source of pharmaceutical pollution.
"Hopefully, this study will lead to pharmaceutical companies taking ownership of their discharges," said environmental toxicologist Chris Metcalfe of Trent University.
Another known source of pharmaceutical pollution include the antibiotics and hormones fed to farm animals, with hormonal imbalances detected in fish downstream of feedlots. Drugs applied to the skin may also be washed off when people bathe or shower, and drugs excreted in sweat may enter the water supply when clothes are laundered. In addition, hospitals, nursing homes and other medical facilities will commonly dump expired and unused drugs directly down the drain, or flush them down the toilet.
Discharges of pharmaceutical products or ingredients are not regulated by the FDA.