From Herbal Teas to Wetlands: The Quiet Spread of Emerging Pollutants and What a New Article Collection Reveals

An ever-growing stream of chemical substances that most monitoring programmes never routinely measure is now the focus of a dedicated article collection in Discover Applied Sciences, introduced by an editorial from Mashura Shammi and Shafi M. Tareq published on 28 October 2026. The collection, titled “Emerging pollutants: occurrence, monitoring and health risk,” gathers eight articles on contaminants ranging from toxic metals in herbal teas and river sediments to antibiotic residues, endocrine disruptors, microplastics in cosmetics, ionizing radiation, and herbicide leaching in tropical agricultural soils. The editorial argues that the pursuit of economic growth and consumer convenience in disposable products, combined with agricultural demands for pesticides and medical demands for antibiotics and other pharmaceuticals, has produced an ever-increasing number of chemical innovations and products in the global market, and with them a silent yet global problem posed by emerging pollutants.

Emerging pollutants, as the editors describe them, are chemical substances whose complexity and severity pose unprecedented threats to both ecosystems and public health amid rapid industrialization and urbanization. Many of these substances are endocrine-disrupting chemicals that, according to the editorial, affect sexual development in children and humans and are also ecologically damaging. Existing pollution problems such as heavy and toxic metals, agricultural pesticides, antibiotics, and ionizing radiation still pose a silent threat to planetary health in many developing countries. A particularly consequential interaction is highlighted in the collection: antibiotic residues in sewage, hospital, and pharmaceutical wastewater, in the presence of heavy metals and microplastics, increase antimicrobial resistance and antimicrobial resistance genes, a combination that the editors frame as a growing global concern.

The collection’s first article, by Miri and colleagues in 2025, examined the emerging threat posed by the consumption of herbal products and the associated carcinogenic risk in Iran. Herbal products have been used for thousands of years in many regions of the world, and over the last few decades their use for weight loss, beauty care, and grooming has become increasingly popular among young and middle-aged people, with many people regularly consuming herbal teas made from various herbal plant ingredients. The study reported the presence of lead, cadmium, and arsenic in many herbal brands containing green tea, cinnamon, hibiscus, cumin, juniper, fennel, and other herbal extracts. Although the hazard quotient and cancer risk were found to be minimal, the authors underscored the need for consumer awareness of the potential harm, and the editorial notes that weight-loss herbal products in particular require strict oversight by regulatory agencies and monitoring of toxic metals and other toxic substances.

Heavy metal contamination of major river systems is addressed in a second research article, which focused on the Middle Gangetic Plain, a region the editorial describes as remaining under-researched. The study found high ecological risk, especially for cadmium, lead, and mercury, as well as potential public health risks via the food chain and sediment resuspension. The direct discharge points for domestic waste were receiving heavy metal loads, highlighting point-source pollution, while confluence points and agricultural fertilizer runoff were also significantly loaded with heavy metals. The authors urged river management and policy development to mitigate impacts in densely populated areas, a recommendation the editorial links to the broader need for stronger data-driven policies and governance across developing regions.

On the remediation side, Tao and colleagues in 2025 reported the frequent presence of sulfonamide antibiotics along with cadmium in water bodies and tested the wetland plant Acorus calamus as a phytoremediation agent for the combined pollution. Phytoremediation is described in the collection as a significant biotechnological method for removing emerging pollutants such as antibiotics, heavy metals, and radionuclides. In the study, Acorus calamus removed cadmium and sulfamethoxazole in wetlands, simultaneously speeding up sulfamethoxazole breakdown by approximately 18 percent and increasing cadmium removal by nearly 30 percent at the tested concentrations. The plant showed good tolerance to the pollutants, with no major effects on its growth or most antioxidant enzymes, except for a notable rise in catalase activity, and under stress conditions it adapted its photosynthesis by increasing chlorophyll levels in the leaves. Plant roots retained much higher levels of cadmium and sulfamethoxazole than the leaves did, and the authors concluded that Acorus calamus is a resilient and effective option for wetland-based phytoremediation of combined cadmium and sulfamethoxazole pollution.

Ionizing radiation is the subject of a review article by Eddy and colleagues examining the health, economic, and environmental impacts of radiation in Nigeria, covering both natural sources such as radon and terrestrial radiation and human-made sources such as medical X-rays and industrial activities. The review covers various radiation types, including alpha, beta, gamma, X-rays, and neutrons, and associated health risks ranging from acute effects such as burns to long-term consequences such as cancer and genetic mutations. Environmental concerns include contamination of water bodies and ecosystems, with real-world case studies highlighting risks posed by naturally occurring radioactive materials in oil fields and mining sites. The review stressed the urgent need for proper radioactive waste management and strong regulatory oversight. Despite the presence of the Nigerian Nuclear Regulatory Authority, challenges persist, including limited resources, weak infrastructure, and low public awareness, and the review emphasized improvements in updating safety protocols, strengthening international partnerships, and enhancing monitoring technologies as means of strengthening radiation safety and regulatory compliance in the country.

Pesticide contamination of groundwater and soil is examined through the case of atrazine, a white herbicide frequently detected in groundwater worldwide and used for broadleaf weed control in crops such as corn, sorghum, sugar cane, maize, wheat, and rice. The authors studied the thermodynamic behavior of atrazine sorption and desorption in three soil types from sugarcane fields, and their findings imply that soil organic carbon content and mineralogy significantly affect atrazine mobility and persistence. Sorption behavior of atrazine in soil was stronger than desorption, and the desorption process was slow, complex, and exothermic under laboratory conditions. Soils with higher leaching potential indices were correlated with increased desorption potential and lower retardation factors, meaning leaching-prone soil is at great risk of atrazine leaching into groundwater. This, the authors note, can further increase the risk of groundwater pollution and health risks in tropical agricultural countries such as Thailand.

Two reviews in the collection focus on chemicals encountered in everyday products. A comprehensive review highlights the association between specific endocrine disruptors, including phthalate esters, bisphenol A, diethylstilbestrol, perfluoroalkyl substances, polybrominated diphenyl ethers, zearalenone, polycyclic aromatic hydrocarbons, and fluorene-9-bisphenol, and health outcomes including reproductive toxicity, earlier puberty in girls, and increased risks of obesity or cancer development later in life. Endocrine disruptors are described as chemicals that accumulate in the environment over time and can enter the body through the food chain and through continuous exposure to various home and office decorative items, including furniture. The review urges attention to the vulnerability of adolescents undergoing sexual development, public awareness of exposure pathways, and the urgent need for further research and public health interventions. In a separate scoping review, Thomas and colleagues mapped exposure routes, both dermal and oral, of common polymers such as polyethylene for microplastics in cosmetics and personal care products and assessed their impact on human health, finding that polyolefins, plastic microspheres, and microbeads were the most detected microplastics in cosmetics and a wide range of personal care products, with the most common exposure routes being oral and dermal.

That microplastics review identified human health risks including loss of cell viability, potential endocrine disruption, and systemic presence in body fluids, alongside environmental persistence and entry into the food chain. Because both men and women use a range of rinse-off personal care products, including facial scrubs, facewashes, exfoliators, body gels, cleansers, anti-callus scrubs, and toothpastes, the review concluded that safer alternatives should be developed and that global policies and regulations must be implemented to restrict the use of microplastics in personal care products. A further comprehensive review by Chemeda and colleagues explores the relationship between antibiotic resistance genes and heavy metal contamination, finding that sewage discharges along with industrial and hospital effluents are major contributors of antibiotic residues, resistant microorganisms, and heavy metals to environmental systems, and that these three components together facilitate the broader dissemination of antimicrobial resistance and resistance genes. The review showed increasing evidence of heavy metal contamination and the persistent development of resistance genes, and concluded that understanding the complex relationships between antibiotics and heavy metals is essential for designing effective strategies to prevent and mitigate the propagation of resistance genes.

The editors are candid about the collection’s limitations: four of the eight articles are review articles that identify sources, transport pathways, public health vulnerabilities, and environmental risks, while the other four identified the presence of emerging pollutants in different matrices, often involving combinations such as toxic metals and antibiotics, their transport pathways, and combined remediation measures. The editorial calls for enhanced detection capabilities of emerging pollutants in different matrices, low-cost yet effective remediation methods, and research into cumulative and long-term effects to protect ecosystems and human health, especially in developing regions. It also notes that detecting emerging pollutants often requires expensive instrumentation that is not readily available in the developing world, and that industry-academia-regulatory agency collaboration can play a crucial role in emerging pollutant research. The implications, the editors conclude, underscore the urgent need for stronger data-driven policies, regulations, and governance, greater transparency, and greater public awareness of emerging pollutants.

Subject of Research: Emerging pollutants in the environment, their monitoring, health risks and remediation

Article Title: Emerging pollutants: occurrence, monitoring and health risk

Article References: Shammi, M., & Tareq, S. M. (2026). Emerging pollutants: occurrence, monitoring and health risk. Discover Applied Sciences, 8(11), Article 1276. https://doi.org/10.1007/s42452-026-09665-z

Image Credits: AI Generated

DOI: 10.1007/s42452-026-09665-z

Keywords: emerging pollutants, heavy metals, antimicrobial resistance, endocrine disruptors, microplastics, phytoremediation, atrazine, ionizing radiation, groundwater contamination, herbal products, public health, environmental monitoring