Air pollution tolerance index of Persea bombycina: Primary food plant of endemic muga silkworm (Antheraeaassamensis).

Air pollution poses a significant threat to human health, ecosystems, and the livelihood of tribal communities. This study focuses on understanding the impact of air pollution on the primary food plant som (Persea bombycina Kost.) of the endemic Muga silkworm (Antheraea assamensis) and its implications for muga silk production. The study was conducted at two sites in northeastern India, one free from atmospheric pollutants (FAP) and the other affected by pollution from an oil refinery (PAS). Various atmospheric pollutants, including particulate matter, hydrocarbons, and heavy metals, were found to be higher at the PAS site. The study investigated biochemical parameters like ascorbic acid, relative water content, total chlorophyll, and extractable pH in the leaves of P. bombycina to determine its air pollution tolerance index (APTI). Results showed that the ascorbic acid content in the leaves increased significantly at the PAS site (p < 0.05), indicating the plant's adaptation to air pollution stress. Similarly, the APTI values were higher during summer compared to winter, suggesting better tolerance during the former season. Positive correlations were found between APTI and ascorbic acid content (p < 0.05), emphasizing the role of ascorbic acid as an antioxidant in mitigating the effects of air pollution. The study highlights the importance of understanding the tolerance levels of P. bombycina to develop protective measures for sustaining Muga silk production in the face of rapid industrialization and increasing pollution. This research can aid policymakers in balancing economic growth with environmental conservation and protecting traditional practices of tribal communities.

Biotite as a geoindicator of rare earth element contamination in Gomati River Basin, Ganga Alluvial Plain, northern India.

Rare earth elements (REE) are emerging as modern high-technology-related novel micro-contaminants in freshwater aquatic systems and are therefore attracting global attention due to their potential human health risks. The Gomati River (a tributary of the Ganga River) sediments were analyzed for REE concentrations to establish REE contamination and to identify biotite mica mineral as a geoindicator. Chondrite-normalized REE pattern of the river sediments and biotite mica mineral were similar and depict a strong light REE (LREE) enrichment and relatively flatter heavy REE (HREE). The maximum total REE (∑REE) concentration increased from 323 µg/g in 2012 to 673 µg/g in 2019. In the ∑REE, LREE contribution was > 80%, because of anthropogenic inputs, mainly petroleum-cracking catalysts and other high-technology-based products. The XRD analysis and the geochemical signature of the Gomati River sediments reveal the meaningful existence of biotite mica mineral. A distinct downstream REE enrichment pattern was identified in biotite from the mica-rich bedload sediments. The scanning electron microscopy-energy dispersive X-ray (SEM-EDX) mapping images of biotite also revealed the precipitation of Lanthanum, at the weathered edges, during the early stage of mineral weathering. Biotite mica was identified as a geoindicator for the assessment of REE contamination in the Gomati River and the Hindon River Basin of the Ganga Alluvial Plain. Future research is needed for the application of biotite mica mineral as a geoindicator that can help the environmental scientists to contribute more effectively to the interdisciplinary efforts in River Science.

Mapping human health risk by geostatistical method: a case study of mercury in drinking groundwater resource of the central ganga alluvial plain, northern India.

Human health is "at risk" from exposure to sub-lethal elemental occurrences at a local and or regional scale. This is of global concern as good-quality drinking water is a basic need for our wellbeing. In the present study, the "probability kriging," a geostatistical method that has been used to predict the risk magnitude of the areas where the probability of dissolved mercury concentration (dHg) is higher than the World Health Organization (WHO) permissible limit. The method was applied to geochemical data of dHg concentration in 100 drinking groundwater samples of Lucknow monitoring area (1222 km2) located within the Ganga Alluvial Plain, India. Threefold (high to extreme risk) and twofold (moderate risk) higher dHg concentration values than the WHO permissible limit were observed in all of the groundwater samples. The generated prediction map using the probability kriging method shows that the probability of exceedance of dHg is the highest in the northwestern part of the Lucknow monitoring area due to anthropogenic interferences. The hotspots with high to very high probability are potentially alarming in the urban sector where 32.4% of the total population is residing in 6.8% of the total area. Interpolation of local estimates results in an easily readable and communicable human health risk map. It may help to consider substantial remediation measures for managing drinking water resources of the Ganga Alluvial Plain, which is among the anthropogenic mercury emission-dominated regions of the world.