The discovery of antibiotics is one of the most important medical discoveries in history (Hutchings, Truman and Wilkinson, 2019). Over the last century, we have seen drastic development of new antibiotics, which are used in a number of cases, such as treatment of infections, treatment of cancer, and in aquaculture (Hutchings, Truman and Wilkinson, 2019). Antibiotics work by disrupting a bacterial cell’s natural processes, such that the cell either dies or stops multiplying (Kohanski, Dwyer and Collins, 2010). Though they proved to be useful in medicine, antibiotics are very difficult to biodegrade (Araújo, et al., 2020). Due to the widespread use of antibiotics and poor regulation, high antibiotic concentrations are present in ecosystems, and this antibiotic pollution has numerous effects on the environment (Kraemer, Ramachandran and Perron, 2019).
Antibiotics that have high absorptive properties accumulate within soil, whereas antibiotics with poor absorptive properties make their way into aquatic systems (Polianciuc, et al., 2020). Exposing bacteria to high concentrations of antibiotics can decrease heterogeneity, while favouring resistant or tolerant microbes (Nijsingh, Munthe and Larsson, 2019). Exposure to low concentrations of antibiotics results in activation of SOS response (a bacterial response to DNA damage), which increases mutations within microbial population, thus enhancing genetic diversity (Kraemer, Ramachandran and Perron, 2019).
Microbes are a crucial component of ecological functions like nutrient cycling, carbon cycling, nitrification, denitrification, and decomposition (Kraemer, Ramachandran and Perron, 2019). When antibiotics enter an ecosystem, they disrupt these natural processes to which bacteria are critical, including disrupting bacterial enzymes required for soil activity (Kraemer, Ramachandran and Perron, 2019). Additionally, antibiotic residues can result in ecotoxicity for plants, disturbing photosynthetic processes and causing an oxidative stress response (Polianciuc, et al., 2020).
In aquatic systems, antibiotic pollution severely affects algal populations by altering their metabolic pathways, leading to population decline (Liu, et al., 2021). Antibiotic pollution is less severe in its impacts on fish; however, bioaccumulation occurs in species higher in the food chain, which poses a significant threat to top predators, as well as humans that consume these fish (Liu, et al., 2021).
To combat antibiotic pollution, a possible strategy is the targeted ecopharmacovigilance (EPV). EPV refers to the practices involved in evaluating and preventing unfavourable effects of pharmaceutical substances in the environment (Holm et al., 2013). A study conducted by Wang, et al. (2019) examined the use of targeted EPV to control the pollution of ofloxacin (a quinolone antibiotic used to treat bacterial infections) in China. In a rural community, a pond was heavily contaminated with ofloxacin due to the disposal of the substance by community clinics and landfills. Targeted EPV was found to be very effective in minimizing residual levels of ofloxacin in pond water (Figure 1). After one year of the intervention, the concentration of ofloxacin was at 0.1% of the initial concentration (Wang, et al., 2019).
While antibiotics and antibiotic development are of the utmost importance in healthcare, it is equally important to invest in their responsible disposal. The effects of antibiotic pollution have severe impacts on the environment; however through strategies like target EPV, we can work towards managing antibiotic pollution.
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