Arsenic exposure has been implicated in various malignancies, including head and neck cancers (HNCs). However, the association between arsenic exposure and HNC development remains unclear. This systematic review aimed to assess the relationship between arsenic exposure and the risk of developing HNCs. This study adhered to PRISMA guidelines. A systematic search of PubMed, Embase, Scopus, and Web of Science was conducted from inception to January 2025 to identify relevant studies. Observational studies reporting the association between arsenic and HNCs were included. Two independent reviewers performed study selection, data extraction, and risk of bias assessment using the NIH criteria. A total of 24 studies met the eligibility criteria, including 35,641 cases and 4,631 controls. The mean age of cases was 50.3 years, while controls had a mean age of 57.7 years. Nineteen studies assessed nasopharyngeal/laryngeal cancers, and 13 investigated oral cancers. Environmental/occupational arsenic exposure was reported in 14 studies, while 11 studies measured arsenic levels in biological samples. Geographical differences in exposure outcomes were observed, with significant associations reported in studies from Tunisia, Chile, Brazil, and Taiwan, while studies from the UK, Finland, and a multicenter European study found no significant relationship. Blood, hair, soil, and drinking water arsenic concentrations varied across studies, with inconsistent findings. The findings suggest a potential link between arsenic exposure and HNCs, particularly in regions with high environmental contamination. However, heterogeneity in exposure assessment and study design limits definitive conclusions. Further well-controlled studies are needed to clarify the association and underlying mechanisms.
This study examines the microbiological and mycotoxicological quality of common wheat in Romania in the extremely dry 2023-2024 agricultural year. Common wheat grown in the West Plain, Southern Hilly Area, Transylvania, and northern Moldavia (45-48 degrees N, 21-27 degrees E) had higher moisture content, water activity, Fusarium-damaged kernels, and deoxynivalenol levels. This was due to moderate temperatures, abundant precipitation, and soil water reserves in May, followed by moderate drought from June to August. Conversely, common wheat from the Oltenia Plain, the Southern Plain, and southern Moldavia (43-46 degrees N, 23-28 degrees E) had the lowest contamination levels, attributed to extreme temperatures and drought during June-August. Common wheat from Dobrogea (45 degrees N, 28 degrees E) showed the highest total fungi contamination, which was influenced by precipitation at harvest. Although microbiological and mycotoxicological contamination was low, it negatively affected the physico-chemical and sensory-colorimetric parameters of common wheat, particularly in the West Plain, Oltenia Plain, and Dobrogea. Consequently, there could be significant economic losses for farmers, storekeepers, millers, and bakers, as well as a decline in the quality of finished foods. Moreover, the coexistence of deoxynivalenol and total aflatoxins in common wheat grown in the northwest of the country indicates the spread of contamination due to dry conditions and climate change.
Polycyclic aromatic hydrocarbons (PAHs) are bonded organic compounds with numerous structures with different toxicity levels. They can be of low molecular weight with 2-3 rings or high molecular weight with more than four rings and are persistent in nature. They possess high molecular weight and boiling point, hydrophobic with minimal solubility in water, and lipophilic with high solubility in organic solvents. With the gain in molecular weight, their susceptibility to oxidation-reduction decreases. They are generated during incomplete combustion of organic materials. They can be natural, such as forest fires, or artificial agents, such as coal, oil, wood burning, smoke, and auto-emissions. Due to strong molecular bonds and structural complexity, PAHs are highly malignant under normal conditions. They cause environmental damage due to improper handling and disposal in the surrounding air, water, soil, etc. PAH contamination is highly toxic because of mutagenic and potentially immune toxicants, often resulting in higher workplace casualties. Various physical, biological, and chemical processes remediate the PAHs in contaminated land. Indigenous microbial communities can effectively degrade it in-situ or ex-situ conditions. The degradation process depends on the type of microorganism, its life cycle, PAH substrate, pH, temperature, pressure, and the reaction mechanism. The present article discusses current literature, chemistry, natural and anthropogenic sources of generation, impacts on the environment, biota, etc., merits of physical, biological, and chemical remediation mechanisms with emphasis on microbial degradation, and novel options of technology intermix suitable for sustainable remediation outcomes.
As the demand for fish increases, the amount of wastewater generated from fishponds is also increasing with potential environmental and public health effects from their indiscriminate disposal. This study aimed at comparative analyses of the physicochemical and heavy metal constituents and potential DNA damage by wastewaters from natural and artificial fishponds using Allium cepa assay. A. cepa were grown on 3.13, 6.25, 12.5, 25.0, and 50.0% (v/v; wastewater/tap water) concentrations of each wastewater. At 48 and 72 h, respectively, genotoxic and root growth inhibition analyses were carried out on the exposed onions. The onion root tips exposed to wastewaters showed a significant (P < 0.05) inhibition of root growth and cell division in a concentration-dependent manner. Additionally, chromosomal abnormalities like spindle disturbances, sticky chromosomes, micronucleus, bridges, and binucleated cells were observed in the exposed onions and their induction was higher significantly relative to the negative control. Generally, wastewater from the natural fishpond caused higher chromosomal aberrations than the wastewater from artificial fishpond. It is our belief that the cytotoxicity and genotoxicity observed in the onions were primarily caused by heavy metals like Cr, Cd, Fe, Pb, Cu, and Zn found in the wastewaters. These metals also showed a significant carcinogenic and non-carcinogenic risks in children and adults with Cd as the highest contributor to these detrimental risks. Ingestion route was the major exposure route to the toxic metals in these wastewaters. Wastewater from the natural fishpond showed a higher health risk than the wastewater from the artificial fishpond. These findings suggest that the wastewaters from natural and artificial fishpond contain compounds that might induce cytogenotoxicity in exposed organisms.
Bisphenol A (BPA) accumulates in the environment at lethal concentrations because of its high production rate and utilization. BPA, originating from industrial effluent, plastic production, and consumer products, poses serious risks to both the environment and human health. The widespread aggregation of BPA leads to endocrine disruption, reactive oxygen species -mediated DNA damage, epigenetic modifications and carcinogenicity, which can disturb the normal homeostasis of the body. The living being in a population is subjected to BPA exposure via air, water and food. Globally, urinary analysis reports have shown higher BPA concentrations in all age groups, with children being particularly susceptible due to its occurrence in items such as milk bottles. The conventional methods are costly with a low removal rate. Since there is no proper eco-friendly and cost-effective degradation of BPA reported so far. The phytoremediation, green -biotechnology based method which is a cost-effective and renewable resource can be used to sequestrate BPA. Phytoremediation is observed in numerous plant species with different mechanisms to remove harmful contaminants. Plants normally undergo several improvements in genetic and molecular levels to withstand stress and lower levels of toxicants. But such natural adaptation requires more time and also higher concentration of contaminants may disrupt the normal growth, survival and yield of the plants. Therefore, natural or synthetic amendments and genetic modifications can improve the xenobiotics removal rate by the plants. Also, constructed wetlands technique utilizes the plant's phytoremediation mechanisms to remove industrial effluents and medical residues. In this review, we have discussed the limitations and futuristic advancement strategies for degrading BPA using phytoremediation-associated mechanisms.
Soil pollution by heavy metals can cause continuing damage to ecosystems and the human body. In this study, we collected nine fresh topsoil samples and 18 maize samples (including nine leaf samples and nine corn samples) from agricultural soils in the Baiyin mining areas. The results showed that the order of heavy metal concentrations (mg/kg) in agricultural soils was as follows: Zn (377.40) > Pb (125.06) > Cu (75.06) > Ni (28.29) > Cd (5.46) > Hg (0.37). Cd, Cu, Zn, and Pb exceeded the Chinese risk limit for agricultural soil pollution. The average the pollution load index (4.39) was greater than 3, indicating a heavy contamination level. The element that contributed the most to contamination and high ecological risk in soil was Cd. Principal component analysis (PCA) and Pearson's correlation analysis indicated that the sources of Ni, Cd, Cu, and Zn in the soil were primarily mixed, involving both industrial and agricultural activities, whereas the sources of Hg and Pb included both industrial and transportation activities. Adults and children are not likely to experience non-carcinogenic impacts from the soil in this region. Nonetheless, it was important to be aware of the elevated cancer risk presented by Cd, Pb, and especially Ni. The exceedance rates of Cd and Pb in corn were 66.67% and 33.3%, respectively. The results of this research provide data to improve soil protection, human health monitoring, and crop management in the Baiyin district.