Exposure to complex organic substances present in textile wastewater has been considered a threat to human health and aquatic organisms. Development of appropriate treatment mechanisms, as well as sensitive monitoring assays, is considered important in order to safeguard and protect the delicate natural equilibrium in the environment. In this study, combined coagulation/flocculation and electrohydraulic discharge (EHD) system were explored for treatment of textile wastewater. Pre- and post-treatment samples were used to evaluate process efficiencies. Process efficiencies were evaluated using physicochemical characteristics, and cytotoxicity and inflammatory activities induced in macrophage RAW264.7 cell line. The RAW264.7 cell line was evaluated as an alternative to animals and human blood culture models, whose routine applications are hindered by stern ethical requirements. The toxicity of effluent was evaluated using WST-1 assay. The inflammatory activities were evaluated in RAW264.7 cell culture supernatant using nitric oxide (NO) and interleukin 6 (IL-6) as biomarkers of inflammation. The levels of NO and IL-6 were determined using the Griess reaction assay and double-antibody sandwich enzyme-linked immunoassay (DAS ELISA), respectively. Overall, the results of this study show that combined approaches and not the single EHD system are sufficient for complete removal of chemical oxygen demand (COD) and total organic carbon (TOC), toxicity and inflammatory activities in textile wastewater. The study shows that induction of NO and IL-6 secretions in macrophage RAW264.7 cells is a very sensitive model system to monitor the efficiency of textile effluent treatment processes.

Indirect potable reuse systems, which consist of wastewater treatment (WWT) and soil aquifer treatment (SAT), offer advantages such as their low cost and the underground storage of reuse water. In this study, the dissolved organic matter (DOM) profile of a sequential treatment system (i.e. WWT followed by SAT) was investigated using a pilot-scale SAT reactor. In addition, the biological DOM removal characteristics in the vadose zone of the SAT, which were found to play an important role in DOM removal for the entire SAT, were investigated using lab-scale reactors (LSRs). Composition of the removed DOM by WWT and SAT showed that the majority fraction of the removed DOM was different for the WWT (hydrophobic neutral 27.9%) and SAT (hydrophobic acids (HoA) 29.1%), suggesting that SAT exhibits unique DOM removal characteristics that contribute to water reclamation. Biological DOM removal was confirmed using the LSRs, and changes in the DOM removal characteristics 10–20 cm from the top of the vadose zone in the LSRs were revealed on the basis of the DOM fractionation and a BIOLOG assay, suggesting that microbial activity in the lower layer of the vadose zone contributed to the unique removal of the HoA fraction in the SAT.

Production, distribution, and disposal of pharmaceutical products, including beta-blockers, have become a global issue. Beta-blockers are known to persist in the environment months after their release and may result in the disruption of the homeostatic system in non-target organisms. Here, we study the bioconcentration of three of the most commonly used beta-blockers and their effect on the regeneration of Girardia dorotocephala, a freshwater brown planarian. Acute toxicity tests determined LC₅₀s for acebutolol, metoprolol, and propranolol to be 778 mg/L, 711 mg/L, and 111 mg/L, respectively. The quantification and analysis of beta-blocker bioconcentration during acute exposure were performed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). After 4 days of exposure to beta-blockers, the bioconcentration drastically decreased for all three beta-blockers at all exposure levels, suggesting that an effective mechanism to reduce uptake or excrete beta-blockers could be present. Additionally, Girardia dorotocephala were cut proximal to the head and the quality of regeneration was documented from each fragment daily. No significant difference was visually observed after 2 weeks of regeneration between the brown planarians placed in beta-blocker solution and those placed in control solution.

Traditional medicine (TM) including Ayurvedic medicines, traditional Chinese medicines and nutraceuticals are popular across the globe as dietary supplements and traditional and alternative medicines. Health risks from these remedies continue to present serious concerns, with occurrences of poisoning by metals and metalloids present at concentrations above acceptable regulatory standards. This review overviews the prevalence of TM use, cases of metal and metalloid poisoning following TM consumption, and forms of TM contamination and adulteration. The review summarises regulations by the World Health Organization (WHO) and other relevant bodies. Finally, the review recommends how to protect consumers.

Currently, the urgency of balancing rice production and environmental risk from nitrogen (N) fertilization is gaining scientific and public attention. As such, a field experiment was conducted to investigate the rice yield and the fate of applied-¹⁵N for Yangliangyou 6 (a two-line hybrid cultivar) and Lvdaoq 7 (an inbred cultivar) using 10 combinations of N rates and splitting ratios in the middle reaches of the Yangtze River. The results showed that N application primarily affected fertilizer N loss to the environment, followed by plant N absorption, but had little effect on grain yield. Generally, there was no significant increase in grain yield and N accumulation in the aboveground plant when N inputs surpassed 130 or 170 kg ha⁻¹. Fertilizer N residue in soil peaked at approximately 48 kg ha⁻¹ at an N rate of 170 kg ha⁻¹ for both varieties; however, a sharp increase of fertilizer N loss occurred with further incrementally increasing N rates. Although a higher ratio of panicle-N fertilizer together with a lower ratio of tillering-N fertilizer at rates of 130, 170, and 210 kg ha⁻¹ had no grain yield benefit, it promoted aboveground N accumulation and plant N accumulation derived from fertilizer, and it reduced the amount of N residue in soil and N loss to the environment. Overall, reducing tillering-N ratios and increasing panicle-N ratios at an N rate between 130 and 170 kg ha⁻¹ using fertilizer rates of 90–0–40 kg ha⁻¹ and 90–40–40 kg ha⁻¹ N at basal-tillering-panicle initiation stages could reduce the adverse environmental risks of chemical N from rice production without sacrificing rice yield.

Formation of trihalomethanes (THMs) through excessive chlorination in the supplied water and its carcinogenic nature is a public health concern in many parts of the world, including a couple of neighboring countries in Asia. However, the issue was not yet addressed either in the public health policy or in academia in Bangladesh. Therefore, the objectives of this study are to determine the THM concentration in supplied water, its multiple pathways to the human body, and an estimation of resultant carcinogenic risk to urban dwellers in six different regions of Dhaka city. Thirty-one supplied water samples were collected from 31 different water points located in Purana Paltan, Naya Paltan, Kallyanpur, Shyamoli, Malibagh-Rampura, and Panthapath regions in premonsoon time. Total chlorine and chlorine dioxide (ClO₂) and trihalomethane (THM) concentration were determined using UV-VIS spectrophotometer; total organic carbon (TOC), total inorganic carbon, and total carbon concentration were measured using TOC analyzer, and chloroform concentration was determined by applying gas chromatography-mass spectroscopy (GC-MS-MS) in the supplied water samples. Research findings indicate that THM concentration exceeded the USEPA acceptable limit (80 ppb) in all regions except Panthapath. Study results showed that carcinogenic risk via ingestion was higher than the USEPA acceptable limit of 10⁻⁶. Carcinogenic risk via dermal absorption and inhalation exposure was lower according to USPEA acceptable limit. To conclude, this study represents the current knowledge about THM concentration in supplied pipeline water and adverse health risk, which signifies that regulatory measures should be taken to reduce the THM concentration.

In this study, we investigated the Sb(V) adsorption on ferrihydrite (Fh) at different pH values, in the presence and absence of common competing anions in soil such as phosphate (P(V)) and arsenate (As(V)). Batch adsorption experiments, carried out at pH 4.5, 6.0, and 7.0, showed a greater affinity of Fh towards P(V) and As(V) with respect to Sb(V), especially at higher pH values, while the opposite was true at acidic pH. The capacity of Fh to accumulate greater amounts of phosphate and arsenate in the 6.0–7.0 pH range was mainly linked to the different acid properties of P(V), As(V), and Sb(V) oxyanions. The Sb(V) adsorption on Fh was highly pH-dependent and followed the following order: pH 4.5 (0.957 mmol·g⁻¹ Fh) > pH 6.0 (0.701 mmol·g⁻¹ Fh) > pH 7.0 (0.583 mmol·g⁻¹ Fh). Desorption of antimonate from Sb(V)-saturated Fh, treated with citric and malic acid solutions, was ~equal to 55, 68, and 76% of that sorbed at pH 4.5, 6.0, and 7.0, respectively, while phosphate, arsenate, and sulfate were able to release significantly lower Sb(V) amounts. The FT-IR spectra revealed substantial absorbance shifts related to the surface hydroxyl groups of Fh, which were attributed to the formation of Fe-O-Sb(V) bonds and supported the formation of inner-sphere bonding between Sb(V) and Fh.

The air pollution problem in Xingtai and Handan is the focus of public attention. The seasonal gray model with fractional order accumulation is proposed to predict the quarterly concentrations of PM₂.₅, PM₁₀, NO₂, and CO in Xingtai and Handan. The new model has higher forecasting performance and can describe the characteristics of seasonal fluctuation very well. The forecasting results indicated that except for the PM₁₀ in Xingtai that will increase slowly, the other indicators in the two places will decrease. The changes of the air quality indicator concentration in different quarters are obvious, and in the same quarter tend to be stable. Except for CO and NO₂ in some seasons, other indicators are in the state of exceeding the standard. The effect of air pollution control is not good. The governance needs to be further strengthened.

This study investigated the growth-dependent role of algal organic matters (AOMs) to achieve high removal efficiency (R.E) of microalgae. The results showed that the microalgae cells produced 96 ± 2% of total AOMs as loose bound AOMSS (LB-AOMs) and 4 ± 1% as cell-bound (CB-AOMs) in exponential phase. In stationary phase, LB-AOMs and CB-AOMs were 46 ± 0.7percentage and 54 ± 0.2 percentage, respectively. The R.Es in exponential and stationary phase were 83 ± 2.6% and 66 ± 1.2%, respectively. It is found that the difference of biomass concentration (between exponential and stationary phase) had no significant impact on the R.E (P > 0.01). Further investigations revealed that LB-AOMs inhibit flocculation in exponential and CB-AOMs in stationary phase; however, CB-AOMs showed stronger inhibition than the LB-AOMs (P < 0.01). The provision of calcium (17 ± 0.9 mg/L) to the culture reduced the AOMs inhibition and improved the R.E from 66 ± 1.2% (in control) to 90 ± 4.2%. An increase in R.E was attributed to the interaction of calcium with AOMs and subsequently acting as a flocculant. The findings of this study can be valuable to improve the performance of auto-flocculation technology, which is mainly limited by the presence of AOMs. Graphical Abstract

Huge amounts of natural bischofite (MgCl₂∙6H₂O) resulting from the mining process of salt lakes often cannot be utilized effectively and are discarded; techniques for reutilization of the discarded bischofite as magnesium resources are limited. The nano-magnesium hydroxide (nano-Mg(OH)₂) synthesized from natural bischofite was firstly used as catalyst for ozonation of antibiotics including sulfathiazole (ST), ofloxacin (OFL), and tetracycline (TC). Rapid ozonation of ST, OFL, and TC was achieved using nano-Mg(OH)₂ as catalyst. The removal rate constant of OFL in the catalytic ozonation treatment (kOFL = 0.512 min⁻¹) was nearly 2.1 times higher than the single ozonation (kOFL = 0.249 min⁻¹). The removal rate constant of ST and TC increased by 23.5% and 32.8% from 0.298 min⁻¹ and 0.384 min⁻¹ to 0.368 min⁻¹ and 0.510 min⁻¹, respectively, when the catalyst was added into the reaction system. The removal rate constant of ST sharply increased from 0.259 to 0.604 min⁻¹ when the reaction temperature increased from 15 to 35 °C while those of OFL and TC changes slightly. The removal efficiency sharply decreased when the initial concentration of ST, OFL, and TC increased from 10 to 500 mg L⁻¹. Both anions and cations could inhibit the removal of ST, OFL, and TC at relatively higher concentrations. The prepared nano-Mg(OH)₂ catalyst could maintain its catalytic activity in the repeated use process. High removal efficiency of typical antibiotics and heavy metals free indicated that nano-Mg(OH)₂ from natural bischofite is a promising ozonation catalyst in terms of antibiotics removal.