Modern medicine and pharmaceutical advances have been indispensable to improving quality of life for hundreds of millions in the United States. However, in recent years, pharmaceutical compounds have become a significant group of environmental pollutants. These compounds could pose risks to human health and have adverse environmental effects.
In fact, pharmaceuticals have been detected worldwide in wastewater, surface water, groundwater, and soil. These compounds enter the environment through many channels, including manufacturing waste, household and hospital solid wastes that end up in landfill leachates, and disposal of unused or expired medicine through sewage systems and landfills.
Recognizing the challenge posed by pharmaceutical compounds in the environment, identifying the best treatment options is crucial. Yet, the best treatment strategy also can prove complex. Treatment of pharmaceuticals presents challenges due to the large quantity, their complex and highly stable chemical structure, and their hazardous nature. Currently available physical and chemical remediation methods—including coagulation/flocculation, filtration, and advanced oxidation processes such as the application of ozone, hydrogen peroxide, and ultraviolet light—are not always applicable, can be cost-prohibitive, and may produce secondary pollution. Thus, there’s a need for more efficient and low-cost remediation technologies.
A leading alternative solution is bioremediation, which is the use of naturally occurring or genetically engineered microorganisms (bacteria and fungi) to consume and break down pollutants in contaminated media, including water, soil, and sediment. Bioremediation has been used for decades as an effective method of degrading various forms of chlorinated solvents and petroleum hydrocarbons in groundwater and soil. As a strategy to address contaminants, bioremediation can be accomplished through natural attenuation, biostimulation, and bioaugmentation in groundwater and soil.
For more than 30 years, bioremediation has been widely studied in environmental biotechnology, and it has been shown that microbial communities in various environments can metabolize a wide variety of chemicals into environmentally acceptable end products. Thus, bioremediation strategies could be effectively applied to pharmaceutical waste streams and at contaminated sites.
Although bioremediation could be a cost-effective technology for removing pharmaceutical waste, biodegradation of pharmaceutical compounds can be challenging, given their diverse and complex chemical structures and relatively low environmental concentrations. Some pharmaceutical compounds, such as ibuprofen, are readily biodegradable, whereas others, such as carbamazepine and trimethoprim, tend to be recalcitrant. Further, biological treatment methods can be sensitive to changes in environmental conditions such as pH, temperature, oxygen, and nutrient levels, as well as sudden changes in the influent’s toxicity levels. These conditions must be optimized and monitored carefully during any bioremediation operation because the treatment’s efficiency directly depends on their stability. An uncontrolled environment may result in the transformation of the pharmaceutical compounds into harmful end products.
Ultimately, the pharmaceutical industry and those responsible for risk management should explore bioremediation strategies to address pharmaceutical contamination in the environment. Bioremediation offers significant advantages and a cost-effective approach, especially when working to remediate contamination at current and former manufacturing sites.