Development of a regional framework for the identification of pharmaceutical compounds in aquatic systems using grey relational analysis

ABSTRACT In India, extensive pharmaceutical manufacturing and the widespread use of over-the-counter medications have led to an increased release of pharmaceutical residues into the aquatic environment. Several studies have reported the occurrence of pharmaceutical compounds in surface water, groundwater and treated wastewater. Despite this, these emerging contaminants are primarily excluded from water quality monitoring. The occurrence of pharmaceutical compounds in aquatic ecosystems of a region is highly influenced by local medicine consumption patterns and the efficiency of sewage treatment processes. This paper presents a region-specific prioritization framework to identify pharmaceutical compounds of concern in Goa, India. Fifty-six compounds were selected for hazard ranking by integrating information on the local disease prevalence, sales data, qualitative sewage analysis and relevant literature. The framework used criteria such as excretion rate, measured environmental concentration, hydrophobicity, ecotoxicity and risk quotient to rank compounds using grey relational analysis. Sensitivity analysis was conducted by varying weights to assess the stability of the ranking. The results identified a few compounds belonging to antibiotics, antihypertensives, hormones and nonsteroidal anti-inflammatory drugs as high priority. It supports water monitoring and policy development aligned with SDGs 6 and 14.