Environmental causes of lung cancer are often overlooked, despite being one of the most common forms of cancer. This review critically analyzes both existing and emerging literature on the impact of human activity on the presence of heavy metals such as arsenic, nickel, chromium, and cadmium in the environment, and assesses their effects on lung cancer. While more research is needed to understand the genomic and epigenomic mechanisms by which these metals affect oxidative stress responses, inflammatory responses, and DNA damage response systems, this work emphasizes the importance of regulating their emissions to protect public health from harmful concentrations or chronic exposure. This study highlights the need to reconstruct toxicity studies not only based on exposure levels but also by considering fluctuations and the synergistic effects of these metals. This approach can lead to a better understanding of lung cancer risk and help in developing more accurate preventive and regulatory policies.

Environmental sustainability has developed a major world-wide apprehension due to the continuous announcement of industrial contaminants into the ecosystem. Tannery effluents are recognised as some of the most hazardous industrial wastewaters due to their complex composition and high pollutant load. These effluents contain substantial concentrations of heavy metals, particularly chromium, along with elevated levels of dissolved solids, chlorides, sulphides and various organic contaminants. Chromium concentrations in untreated tannery wastewater have been reported in the range of 150-3000 mg/L. Furthermore, the wastewater exhibits an exceptionally high organic burden, with biochemical oxygen demand (BOD) values of 2500-8000 mg/L and chemical oxygen demand (COD) levels of 5500-15000 mg/L. The combined presence of toxic metals and recalcitrant organic pollutants significantly exceeds permissible discharge limits, posing serious environmental and public health concerns if released without adequate treatment. Such concentrations greatly exceed the acceptable discharge standards and pose serious risks to aquatic ecosystems and human health. These pollutants suggestively affect aquatic ecosystems, soil productiveness, seed germination and crop efficiency. Heavy metals such as chromium (Cr), lead (Pb), cadmium (Cd) and nickel (Ni) undertake bioaccumulation and biomagnification, foremost to unembellished human health risks together with kidney dysfunction, liver toxicity, respiratory disorders and carcinogenic belongings. This review appraises the physico-chemical characteristics of tannery sewages, their ecological and toxicological influences and presently accessible remediation strategies. Conventional treatment procedures such as coagulation, chemical precipitation, adsorption and membrane filtration have revealed elimination effectiveness of 60-95%, but boundaries together with higher operational cost and sludge cohort restrict their large-scale application. Developing technologies together with bioremediation, phytoremediation, nanotechnology-based adsorbents and hybrid treatment arrangements demonstrate better-quality heavy metal elimination efficiency exceeding 90% under optimised conditions. The study additional classifies major research gaps associated with long-term field-scale authentication, sludge management and maintainable resource recovery. Future investigations should focus on emerging cost-effective, eco-friendly and energy-efficient remediation knowledges for effective tannery wastewater treatment and environmental protection.

This study aims to investigate and document the ichthyofaunal diversity of the Nun River, a previously unexplored tributary of the River Tons in the District of Dehradun, to assess its ichthyofaunal diversity and identify potential conservation needs. Monthly fish collections were done with the help of trained fishermen by using different-sized fishing nets (Mesh size 20–40 mm). However, some fish were also procured from the local fishermen at different sampling sites. Over the course of the study period (August 2022−April 2023), the fish fauna of the Nun River was investigated. Overall, a total of 12 species belonging to 4 orders, 6 families, and 12 genera were recorded. Several anthropogenic stressors such as pollution from agricultural sources, human settlements, and sewage cause severe threats to the fish fauna and aquatic diversity of rivers. Nun River has not been explored earlier for its fish fauna. This is the first attempt made to explore the fish faunal diversity of Nun River. Since this small study area is rich in aquatic faunal diversity, hence its conservation must be given priority.

This review discusses the present status of freshwater fish families – Cyprinidae, Danionodae, and Xenocyprinidae of suborder Cyprinoidei and their conservation status, threats to the species diversity and the community-based conservation across the western Himalayan region. The family Cyprinidae, the largest among freshwater fish, consists of over 1,840 species; whereas Danionidae includes 375 species and Xenocyprinidae comprises around 173 species globally. A total of 35 genera and 76 species have been reported from various rivers and streams of four Indian Himalayan states. Of these, 67 species are classified as ‘Least Concern’, four as ‘Vulnerable’, two as ‘Near Threatened’, and one as ‘Endangered’ species as per the IUCN Red List. Uttarakhand exhibits the maximum species count (63) followed by Jammu & Kashmir (47), Ladakh (38), and Himachal Pradesh (36). The major threats faced by freshwater fish are damming, habitat fragmentation, pollution, invasive species, and climate change. Consequently, modern policies and community-led conservation initiatives play a vital role in preserving these freshwater ecosystems.

Since ancient times, Lichens have been used as a great source for flavouring, dyeing, smoking tobacco, cigars, spices, scenting soaps, and cosmetics and manufacture of Dhoop and Hawan Samagri. Lichens in the field of medication for different disease and disorders are being used from centuries. Traditional knowledge is an important source for the development of new drugs. It has been observed that, strong metabolites from mycobiont culture of lichens and their extracts can be used in various ways to treat many human diseases. Keeping above point in view, an attempt has been made to review the therapeutic potential of lichens in India.