Tracing the Origins: Investigating Anthropogenic and Natural Sources of Persistent Organic Pollutants in the Himalayan River System

The primary objective of this study is to delineate the natural sources of origin of sedimentary organic matter from anthropogenic inputs of the Markanda River in India. The analysis focused on persistent organic pollutants (POPs) including polycyclic aromatic hydrocarbons (PAHs), phthalates, and linear alkylbenzenes (LABs), which are known for their high persistence, potential toxicity, and widespread occurrence. In the current global climate, characterized by an increasing recognition of environmental contamination, particularly in aquatic ecosystems such as rivers, the demand for a robust approach for the identification and monitoring of such pollution has become increasingly imperative. Our proposal aims to utilize the latest developments in biomarker analysis for the purpose of detecting, identifying, and evaluating persistent organic pollutants (POPs) inside the river system. The main objective of this study is to determine the hydrocarbon levels in different areas of the river system, including both natural and human-influenced zones. Moreover, the primary aim of this research is to ascertain potential origins of pollution by examining the associations between various categories of chemicals and patterns of land usage and cover (LULC). The investigation unveiled diverse levels of the examined persistent organic pollutants (POPs), with the mean concentration of polycyclic aromatic hydrocarbons (PAHs) at 23.4 nanograms per gram dry weight (ng/g dw), linear alkylbenzenes (LABs) at 18.1 ng/g dw, and phthalates at 8.3 micrograms per gram dry weight (µg/g dw). The observed differences in concentration levels among various places reveal the presence of spatial heterogeneity, implying that there are contributions from diffuse, nonpoint sources. The primary origins of these anthropogenic hydrocarbons may be attributed to emissions from petroleum and petroleum-derived products, industrial discharges, cultural behaviors, and the disposal of ordinary household trash and sewage. The present research offers valuable insights that may be utilized in the development of mitigation measures and the formulation of policy changes in India and on a worldwide scale. Consequently, this contributes to the wider comprehension of the anthropogenic effects on water ecosystems.