The findings of the study call into question the extent to which good manufacturing practices (GMP) are followed as well as current water treatment technologies that are used to treat wastewater used by the manufacturers.
It reveals that outflow from two New York, US wastewater treatment plants receiving more than 20 per cent of their wastewater from pharmaceutical facilities had drug concentrations 10 to 1000 times higher than outflows from 24 plants nationwide that did not receive pharmaceutical manufacturers’ wastewater.
By contrast, outflow from the wastewater treatment plants that do not receive wastewater from pharmaceutical manufacturing facilities had concentrations that rarely exceeded one part per billion (ppb).
Amongst the drugs that were discovered flowing through the outflows from the two wastewater treatment plants were metaxalone, a muscle relaxant (3,800 ppb), oxycodone, an opioid prescribed for pain relief (1,700 ppb), and methadone, an opioid prescribed for pain relief and drug withdrawal (at least 400 ppb).
The researchers stated that while pharmaceutical concentrations were significantly lower in receiving streams, measurable concentrations were detected as far as 20 miles downstream.
“We have shared this information with both the US Environmental Protection Agency (EPA), and the US Food and Drug Administration (FDA); both agencies have some regulatory authority related to this issue,” said Herb Buxton, coordinator for the USGS Toxic Substances Hydrology Program and one of the co-authors of the study.
“The USGS is a science agency without regulatory authority and provides scientific information used by policy makers and regulators, as well as industry and the public.”
“Currently, the release of these chemicals in wastewaters is not regulated in the US.”
According to www.fiercepharmamanufacturing.com, New York environmental officials identified two pharma facilities and were investigating its related public wastewater treatment plants.
Action
The Environmental Protection Agency (EPA) had requested the co-operation of one of the drugmakers concerning pre-treatment of pharmaceutical waste streams. They had also asked the unnamed company to work with USGS on pre-treating waste prior to discharge to the sewer system.
In response to the findings the FDA said it was ‘carefully evaluating’ the USGS data and were communicating with USGS and EPA to provide its perspective. They were confident the pharmaceuticals found at that concentration posed no risk to human health.
The USGS commented that the unexpected findings meant they had not tested for their presence in finished drinking water. However, they admitted that given these pharmaceuticals were entering streams, it was possible that low levels of some could be present in some drinking-water sources.
Drinking water undergoes a variety of treatments before it reaches the main water supply. Although the treatment processes may not be designed to remove most of these chemicals, many are removed or reduced during treatment.
Other studies
The study is believed to be one of the first in the US to addresses pharmaceutical manufacturing facilities as a source of pharmaceuticals in the environment.
Results from similar investigations worldwide have meant facility discharges from manufacture pharmaceutical products are an under-investigated source of drugs in the environment.
In 2007, a study in India found pharmaceutical concentrations as high as 31000 μg/L in wastewater treatment plant (WWTP) effluent that received substantial discharges from pharmaceutical manufacturing facilities (PMFs).
These discharges resulted in nearby groundwater and surface water concentrations as high as 2500 μg/L.
Similarly, diclofenec concentrations exceeded 20 μg/L in a study conducted in 2008, where Taiwanese WWTP effluent received PMF discharge.
The USGS scientific paper, ‘Pharmaceutical Formulation Facilities as Sources of Opioids and Other Pharmaceuticals to Wastewater Treatment Plant Effluents,’ is published in Environmental Science and Technology, and can be found here.