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Abstract Spent coffee grounds (SCG-1 and SCG-2) were used to study the adsorption of tetracycline (TC) antibiotics and the effects of adsorption time, initial pH, amount of adsorbent and ionic strength were detected. The TC adsorption isotherm on SCG-1 was compared with SCG-2. The results showed that the removal efficiencies of TC (50 mg/L) of SCG-1 and SCG-2 were 83.1% and 97.2%, respectively, shake for 2 h. The probability of adsorption is high and balances in about 20 min. The estimate of parameters got for TC from the Langmuir isotherm saturated adsorption quantity and adsorption balance constant were 64.89 mg/g, 0.0557 L/mg, respectively for SCG-1 and 123.46 mg/g, 0.4735 L/mg, respectively for SCG-2. The adsorption mechanism might be a π–π interaction that occurs in the interface by hydrogen bonding and the between the TC molecular and the SCGs. At last, we found that SCG has a high adsorption size for TC. Highlights • The adsorptive ability of tetracycline on spent coffee grounds (SCG-1 and SCG-2) was investigated. • The adsorption isotherms of tetracycline on SCG-1 and SCG-2 were carried out. • The adsorption rate was very quick with the equilibrium of adsorption within about 20 min. • This SCG-1 and SCG-2 has high adsorption ability for tetracycline. [ABSTRACT FROM AUTHOR]

o -Chlorophenol (OCP) is a priority pollutant that poses serious health threats to the public. The following study designs a simple electrochemical system to monitor the concentration and toxicity of OCP. This system was primarily characterized by the integration of both physicochemical and biological monitoring procedures that had a synergistic effect between the functionalized carbon nanotubes and rhodamine B. This resulted in excellent electrocatalytic activities toward OCP and cellular purine bases. The peak current of OCP was linear with concentrations ranging from 0.05–125.0 μM and the detection limit was 0.028 μM under optimal testing conditions. There was an enhanced voltammetric signal detected that was caused by the guanine/xanthine of human hepatoma (HepG2) cells. The cytotoxicity of OCP to HepG2 cells was assessed using the proposed system. The obtained IC 50 value was 512.86 μM. This study provided a fast, label-free, and low-cost platform for the comprehensive assessment of OCP. This is highly beneficial for simplifying the environmental monitoring process. [ABSTRACT FROM AUTHOR]

The toxicity of polychlorinated biphenyls (PCBs) and their transformation have been intensively investigated in recent years. However, the potential mechanisms of biotransformation in a lake food web remain unclear. To explore the correlation between the PCBs and δ15N values or FAs, six fish species were collected from Dongting Lake, and various tissues were dissected to analyze the δ15N values, FAs and PCBs. Based on the wet weight (ww), the concentration of ∑PCBs 115 ranged from 0.04 to 9.77 ng g−1, and the highest level was found in the gonad of Cyprinus carpio. The toxicity equivalent (TEQ) of PCBs ranged from 0.003 to 2.39 pg g−1, and the highest level was found in the fat of Silurus asotusy. The PCB levels in fish collected from Dongting Lake were at the low end of the global range. PCB28, 52, 95, 99, 101, 105 110, 118, 138, 153, 155 and 209 were found in all tissues. PCBs were distributed in a tissue-specific and species-specific manner in fish. PCB153 and 138 had a positive correlation with the TEQ in liver, gill, intestine and skin of fish on the basis of lipid weight (lw). Docosahexaenoic acid/eicosapentaenoic acid (DHA/EPA) and polyunsaturated fatty acid/saturated fatty acid (PUFA/SFA) had a positive correlation with some PCB congeners in the intestine. PCB52, ∑tetra-PCBs and Ind-PCBs had a positive correlation with the δ15N values in liver of fish on the basis of ww. PUFA/SFA and DHA/EPA might be indicators for the transfer of PCB congeners. • PCBs are distributed in a tissue-specific and species-specific manner in fish. • PCB138 and 153 have a positive correlation with the TEQ in some fish tissues. • DHA/EPA and PUFA/SFA may be indicators for the transfer of PCB congeners. [ABSTRACT FROM AUTHOR]

Abstract In recent years, various industrial activities have caused serious pollution to the environment. Due to the low operating costs and high flexibility, adsorption is considered as one of the most effective technologies for pollutant management. Agricultural waste has loose and porous structures, and contains functional groups such as the carboxyl group and hydroxyl group, so it can be invoked as biological adsorption material. Agricultural waste gets the advantages of a wide range of sources, low cost, and renewable. It has a good prospect for the comprehensive utilization of resources when used for environmental pollution control. This article summarized the current research status of agricultural waste in adsorbing pollutants, which pointed out the influencing factors of adsorption, expounded the adsorption mechanism of biological adsorption and introduced the related parameters of adsorption, proposed the application of adsorbents in engineering including adsorption in liquid and gas phases, at the same time it gave the future development prospect of agricultural waste as adsorbent. Graphical abstract Image 1 Highlights • Summarized the research progress of adsorbing inorganics, organics and gases on agricultural wastes. • Expounded the mechanism of adsorption inorganics and organics by agricultural wastes. • The application of agricultural waste as adsorbents in engineering was introduced. • Future prospects of agricultural wastes as adsorbents were discussed. [ABSTRACT FROM AUTHOR]