Journal of Environmental Health Science and Engineering最新文献

Purpose

Tetracycline, chlortetracycline, and oxytetracycline are commonly prescribed antibiotics. Their extensive use results in a large stream of tetracyclines entering wastewater treatment plants (WWTPs). However, they can still be found in surface waters, which may suggest their incomplete removal in the WWTPs. The study was designed to show (i) how much of tetracyclines may be removed before they enter the environment, (ii) how tetracyclines may be removed after they enter surface water, (iii) how the presence of tetracyclines influence the metabolic activity of bacteria.

Method

Degradation of tetracyclines was studied using two types of inoculum, simulating degradation in WWTPs and rivers. Cell metabolic activity was assessed to show potential risks arising from their appearance in water.

Results

Complete primary degradation in the test with wastewater sludge inoculum was achieved within not more than 14 days. In the test with river water inoculum removal of both tetracycline and oxytetracycline did not exceed 20% in 28 days. Chlortetracycline was transformed rapidly but without considerable structural change. Although no considerable removal was achieved, bacterial activity in the river water test after 28 days was 10 times greater than while starting the test.

Conclusions

The study shows that appropriate retention of sewage in WWTPs must be provided. Otherwise, tetracyclines will accumulate in the environment, where their removal is limited, even though bacterial activity is still relatively high.

The contamination of yogurt and buttermilk (doogh), two widely consumed dairy products, with microplastics (MPs) and phthalic acid esters (PAEs), and subsequently the health effects caused by the contamination of these products on humans, is a potential concern. In this study, the abundance and characteristics of MPs as well as the PAEs concentration in different types of yogurts and buttermilk available in the Iranian market were investigated. The average abundance of MPs in different types of yogurts and buttermilk was between 0.63 and 0.76 and 0.52–0.7 items/mL, respectively. Most detected MPs in yogurt and buttermilk samples were in the size range of 1000–5000 μm with the predominant color and shape of transparent and fiber, respectively. Polyethylene terephthalate (PET) and polyamide (PA) were the dominant polymers in yogurt and buttermilk samples, respectively. The average concentrations of PAEs in different types of yogurt and buttermilk samples were between 5.79 and 11.36 and 1.46–6.93 µg/L, respectively. The findings showed that Di(2-ethylhexyl) phthalate (DEHP) levels in yogurt and buttermilk samples may have a carcinogenic risk for adults and adolescents. According to the results of this study, the intake of MPs and PAEs through high consumption of yogurt and buttermilk should be recognized as a significant source of MPs in the human body.

Heavy metals (HMs) pollution presents a significant challenge for both human health and natural ecosystems on a global scale. This study investigates the pollution of surface sediments resulting from urban runoff, identifies potential pollution sources, and examines the correlation between HMs and two factors: total organic carbon (TOC%) and particle size distribution (PSD). A total of 30 surface sediment samples were collected from three urban channels in the Tehran megacity. The concentrations of key elements, including strontium (Sr), lead (Pb), cadmium (Cd), nickel (Ni), and copper (Cu), were determined using Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES). The mean concentrations of Cd, Ni, Cu, Pb, Sr, were 0.46, 39.80, 161.25, 261.75, 388.50 mg/litter, respectively, following the sequence Sr > Pb > Cu > Ni > Cd. To identify the HMs accumulation, factor analysis(FA) was employed. The HMs rank order based on FA was as follows: 37.7% > 24.4% > 24.1%. According to (FA), the possible accumulation source of Pb and Sr is as different as Cu, Ni, and Cd elements. A significant correlation between Sr with TOC% (r = 0.901, sig = 0.000), Pb with both TOC% and particles < 75µm (r = 0.77, r = 0.63, Sig = 0.000 respectively), while Cu, Ni and Cd with particles < 150µm (r = 0.68, r = 0.81, r = 0.87, Sig = 0.000 respectively) were observed). Overall, the concentration of heavy metals (HMs) demonstrated a significant negative correlation with the particle size of surface sediments.

Trihalomethanes (THMs) are a class of compounds formed when organic substances in water interact with halogen disinfectants such as chlorine. The specific THMs include CHBr₃, CHClBr₂, CHCl₂Br, and CHCl₃. THMs are toxic disinfection by-products (DBPs) that pose potential risks to human health and can be present in ready-to-eat vegetables. Our study examined key variables such as contact time, chlorine concentration, and vegetable type on the formation and absorption of these contaminants. Laboratory simulations involved 22 samples characterized by differing chlorine concentrations, contact durations, and three vegetable types: celery, lettuce, and leek. The result showed that the maximum concentration of THMs (354.73 µg L^− 1) in celery was observed when 300 mg L-1 of chlorine for 15 min was employed. The results demonstrated that contact time significantly affected the formation and absorption of THMs. Celery demonstrates a greater absorption of THMs than others. The evaluation of lifetime cancer risk (LTCR) and hazard index (HI) for THMs across 22 simulated test conditions indicated that CHClBr₂ exhibited the highest LTCR at 7.34 × 10^⁻⁶. Also, the average influence of LTCR for CHBr₂Cl constituted 64%, CHBr₃ accounted for 21%, CHBrCl₂ represented 10%, and CHCl₃ was 5%. The results showed that CHBr₃ had the most effect on the hazard index, while CHCl₃ showed the lowest impact. These findings assist food industry professionals in reducing THM absorption by regulating chlorine concentration and contact time during vegetable disinfection.

Graphical Abstract

Perflorochemicals (PFCs), among which are the most commonly detected perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA), are persistent emergent contaminants of concern in recent times. These compounds have been reported for their cytotoxicity, genotoxicity, carcinogenicity, immunotoxicity, and developmental toxicities. Meanwhile, they have been detected in diverse matrices such as soil, sediment, and, surprisingly, in serum and even breastmilk. Worrisomely, these compounds are detected in drinking water across the globe, aquaculture water, and other surface waters. Thus, it was important to appraise the studies conducted on PFOS and PFOA to provide an overview of the environmental status of contamination regarding them. The present review article sought to provide insights into the occurrence patterns and ecotoxic effects of both pollutants in the water ecosystems within five continents of the world. Based on the information gathered in this article, the (sum PFOS) concentration (ng/L) within the five continents is in the order Europe > Asia > Africa > North America > South America, while the (sum PFOA) level (ng/L) is in the order Europe > Asia > South America > Africa > North America. The study also investigated the previous works that have been conducted regarding the diverse elimination technologies employed for the removal of these pollutants from the aqueous environments, with plasma combined with surfactant process being the most efficient. Generally, studies on PFOS/PFOA are still scanty when compared to those on pharmaceuticals and personal care products (PPCPs), especially in North America. The information gathered in this study could be useful in establishing thresholds of PFOA and PFOS environmental levels and be adopted by appropriate authorities as safety guidelines.

This bibliometric review examines the trends and innovations in biomass utilization for wastewater treatment in Indonesia, emphasizing significant contributions and emerging research areas. Through an analysis of co-authorship networks, co-citation networks, and keyword co-occurrence maps, the review identifies key authors, influential publications, and dominant research themes. The findings highlight that biomass-based methods, including the use of microalgae, macrophytes, and microbial consortia, are central to wastewater treatment efforts in Indonesia. These approaches provide sustainable and cost-effective solutions for pollutant removal and resource recovery. The growing emphasis on keywords such as “biofuels,” “bioplastics,” and “circular economy” reflects a strong interest in integrating wastewater treatment with resource recovery and sustainable practices. However, challenges remain in scaling up technologies like bioreactors and adsorption systems while ensuring cost-effectiveness and operational efficiency. For instance, advancements in microbial fuel cells could enable simultaneous wastewater treatment and renewable energy generation, addressing scalability issues. Similarly, the development of enhanced microbial strains for phytoremediation could improve the treatment of persistent pollutants in water and soil. Future research should aim to bridge gaps through interdisciplinary collaboration and explore underrepresented linkages to unlock further innovation. By addressing these challenges and leveraging emerging technologies, Indonesia can strengthen its wastewater treatment capabilities, contributing to environmental protection, resource efficiency, and sustainable development.

Purpose

Potentially toxic metals can directly induce various adverse effects on reproductive organs or interrupt essential metals' physiological activities. Despite intensive efforts to reduce these metals in the environment, chronic and low-level exposure remains a public health problem. The present study aimed to investigate prenatal metal exposure, including arsenic (As), copper (Cu), lead (Pb), manganese (Mn), rubidium (Rb), selenium (Se), and zinc (Zn), effects on birth weight.

Methods

We collected 579 blood samples before the 16th week of gestation from apparently healthy women with singleton pregnancy in Iran (n = 193) and Japan (n = 386). Blood metal concentrations were measured using inductively coupled plasma-mass spectrometry.

Results

Prenatal blood levels of As, Mn, Pb, and Zn were significantly higher, while Cu, Rb, and Se were significantly (p < 0.01) lower in Iranian participants than in Japanese. Adjusted linear regression analyses and Bayesian Kernel Machine Regression (BKMR) overall exposure–response functions showed inverse relationships between metals and birth weight.

Conclusion

The study findings, using data from geographically diverse countries, suggest prenatal blood metal exposure as a potential risk factor for lower birth weight. Therefore, women of reproductive age should minimize encountering to potentially toxic metals as much as possible.

The presence of bromate in water poses a significant health risk. In order to effectively eliminate bromate from water, this study synthesized a series of ternary Zn-Ni-Al layered double hydroxides with varying Zn/Ni/Al atomic ratios using a co-precipitation method. The adsorbents were characterized using various techniques including XRD, Fourier transform infrared spectroscopy, and N₂ adsorption-desorption isotherms. Among them, ZnNiAl-2 exhibited the highest crystallinity and largest specific surface area (316.1 m² g⁻¹), which was compared to the binary hydrotalcite NiAl-LDH for its ability to adsorb bromate from water. Results demonstrated that the adsorption isotherm of bromate on ZnNiAl-2 followed the Langmuir model, with a maximum adsorption capacity of 120.5 mg g⁻¹, significantly higher than that of NiAl at 75.5 mg g⁻¹, indicating strong adsorption capability and reusability performance. The adsorption kinetics were also found to be in accordance with the pseudo-second-order kinetic model. The mechanism involved both surface adsorption and anion exchange.

In the present study, two most commonly used Perfluoroalkyl substances (PFASs), namely perfluorooctanoic acid (PFOA) and perfluorooctanesulfonate (PFOS), were determined in 45 tap water samples from the city of Isfahan (Iran) by dispersive liquid-liquid extraction (DLLME) and liquid chromatography-mass spectrophotometry (LC-MS) analysis. Risk assessment was also performed to determine the risk to human health. The mean concentration of PFOA was 38.1 ± 26.4ng/L (min = 5.1 and max = 1056ng/L). The mean concentration of PFOS was 33.7 ± 25.09ng/L (min = 4.3 and max = 99.2ng/L). The combined concentrations of PFOA and PFOS were above the US-EPA advisory levels (70ng/L) in 48.8% of the samples. The distance between the sampling locations and the water treatment plant showed no significant correlation (p > 0.05). The results of the risk assessment showed that all calculated hazard quotients (HQ) and hazard indices (HI) are below 1, indicating that the risk to human health from exposure to PFOA and PFOS via drinking water in the city of Isfahan was not high for adults and children. These results indicate a significant contamination of Isfahan tap water by PFOA and PFOS of unknown origin. Further studies are needed on the Zayande-Roud River water as a supplier of Isfahan tap water and the efficiency of the water treatment plant and the role of the water distribution network in PFASs contamination of tap water.