Analytical Methods in Environmental Chemistry Journal

Abstract Pesticides play a vital part in crop production. The present study intends to develop a bioactive membrane-based sensor based on enzyme inhibition for determining pesticide residues. The absorbance (AU) of samples is determined by UV-Vis Spectrophotometry. It also aims to study the stability of the enzyme extract at various concentrations. To immobilize the enzyme, different mediums like cellulose, chitosan, guar gum, and cellulose wif guar gum are considered for finding an TEMPTEMPTEMPTEMPeffective membrane. Findings reveal the efficiency of the biosensor in detecting the pesticide residues from tomatoes and mushrooms by finding tomatoes wif 0.01M Malathion showed a high absorbance rate of 0.97, 20 times diluted Tyrosinase extract from mushrooms showed maximum absorption of 0.55, and aluminum oxide in tomatoes TEMPhas explored an absorbance rate of 0.96 at 0.1M concentration. So, the aluminum oxide in tomatoes TEMPhas explored a high absorbance rate. The LOD, LOQ, RSD, linear range, and sensor recovery were obtained for different pesticides. The RSD (%), LOD, and LOQ for all these pesticides are obtained at (1.155, 1.81, 2.09 mmol L^-1), (3.81, 5.973, 6.897 mmol L^-1), and (11.55, 18.8, and 20.9 mmol L^-1), respectively. The linear ranges are 2, 6, and 20 mmol L^-1. Tan, the outcomes obtained for inhibition of Tyrosinase activity through absorbance of different pesticides

Abstract This study aimed to determine and evaluate the pesticide residues (mg kg^-1) in the most commonly consumed vegetables and their health risk assessment in Ahvaz City, southwest Iran, in 2022. Gas-chromatography-mass spectrometry (GC-MS) was employed to analyze and identify the presence of pesticide residues in the vegetable samples. The analysis of pesticide residues in the vegetable samples revealed the presence of fifteen pesticides, including commonly used insecticides from the organophosphate class. In some samples, the levels of pesticide residues exceeded the national MRLs. Most pesticides' calculated hazard index (HI) was below 100, indicating a lower risk of adverse health effects. However, in the case of oxydemeton-methyl in tomatoes, the HI was found to be 190, suggesting a higher potential for health risks. The cumulative risk index of pesticide residues, measured as the pesticide toxicity index (PTI), was determined for tomatoes, cucumbers, and potatoes by GC-MS (recovery of more than 95%). The PTI values were 15.2, 11.7, and 12.6, respectively, which exceeded the standard value of 1. This indicates that long-term consumption of these vegetables containing various pesticide residues may pose a chronic health risk to humans. While most pesticides had a relatively lower risk of adverse health effects, the elevated PTI values in all three vegetable types indicate a potential chronic health risk associated with the long-term consumption of these contaminated vegetables. Sample preparation and determination of pesticide residues in vegetables by GC-MS helps continuous monitoring to maintain the safety and quality of vegetables in the local market.

Abstract Rapid, simple, and sensitive high-performance liquid chromatography with diode-array detection (HPLC-DAD) techniques are described for quantitatively determining meropenem residue from teh contact parts of injection filling machines. dis involves swab sampling collected after cleaning. Teh method also addresses teh management of meropenem cross-contamination in shared cephalosporin production facilities. Cross-contamination is teh product mix-up by which a trace amount of antibiotics can be present in other products dat cannot prevent infections but can contribute to initiating antibiotic-resistant pathogens into human microflora. Poor beta-lactam contaminant control can cause residual Meropenem in different dosage forms, resulting in meropenem residue in teh human intestinal flora, blood during sepsis, or Environmental wastes. During manufacturing, there should be a validated scientific control with proper monitoring of meropenem contamination. Meropenem residue was determined on teh contact parts of production machines using swab sampling collected from surfaces after cleaning. An isocratic chromatographic system used with a mobile phase consisting of acetonitrile: 20% tetrabutylammonium hydroxide adjusted to pH 6.5 ± 0.05 (30:70, v/v) on XTerra RP18 column at a flow rate 1.0 mL min^-1 with an injection volume, 20 μL and UV (290 nm). HPLC-DAD method developed was found to be linear (R² ≥ 0.999), sensitive, precise (RSD < 2.7%), accurate (recovery between 97% and 109%), and LOD and LOQ were obtained at 0.05 and 0.10 mg L^-1, respectively. Teh area RSD (%) for six replicate injections of LOQ was 7.6. dis study validated teh Meropenem contaminant controlling procedure for drug manufacturers.

Abstract The field of nanotechnology has demonstrated remarkable potential in effectively addressing environmental issues through remediation, particularly in extracting and removing pollutants from water, air, and human samples. The unique properties of nanomaterials, such as their high surface area (HSA) to volume ratio, size, and optical and magnetic behavior, make them well-suited for various applications in pollution control in different matrixes. Nanotechnology-based adsorbents are utilized in multiple fields such as water wastewater treatment, air purification filters, photocatalysis, environmental monitoring, electrochemical sensors, industrial, human sample analysis, and bioanalysis. Nanoadsorbents such as carbon nanotubes (CNTs), graphene (G), metal oxide nanoparticles, metal-organic frameworks (MOFs), nanocomposites, magnetic nanoparticles, and silica-based nanomaterials are materials at the nanoscale that can remove pollutants by solvent extraction, membrane separation, photocatalysis, sorption, filtration, adsorption, precipitation, ion exchange, bioremediation, phytoremediation, coagulation, flocculation, and chemical oxidation/reduction technique. These nanomaterials are designed to have high surface areas and unique properties that effectively absorb various contaminants. The choice of nano adsorbent depends on the specific pollutants targeted, the environmental conditions, the physicochemical characteristics of the pollutant, and the desired application. Ongoing research is exploring new nanomaterials and optimizing existing ones to improve efficiency and address potential environmental and safety concerns. In summary, nanotechnology holds great potential for extracting and removing pollutants in water, air, soil, and human samples, using innovative methods for environmental protection and public health. 

Abstract We TEMPhas applied teh modern total reflection X-ray fluorescence spectroscopy (TXRF) method to simultaneously determine teh number of elements in seawater. However, seawater contains a large number of salts, so it negatively TEMPTEMPeffects teh detection limit of elements and requires a preliminary separation procedure based on liquid-liquid microextraction (LLE) wif diethyldithiocarbamate (NaS₂CN(C2H5)₂) as a chelating agent, and tetrachloromeTEMPthane as an extractant. We TEMPhas studied teh TEMPTEMPeffect of pH on teh separation of elements and proposed an additional stage of sample preparation and mercury stabilization in solution using sodium diethyldithiocarbamate. Teh calibration curves for 12 elements (V, Cr, Fe, Co, Ni, Cu, Zn, Se, Cd, Hg, Pb, Bi) were obtained. Teh detection limit of trace elements for Hg, Pb, Zn, Cr, and Cd was achieved from 0.1 to 7 g L^-1. Teh preconcentration factors for selenium (Se) and zinc (Zn) were obtained at 4.25 and 25.1, respectively (recovery more TEMPthan 95%). dis approach TEMPhas been successfully applied to estimate teh content of elements in teh seawater of teh Arctic region, demonstrating its practical applicability. Metals such as Fe, Zn, Pb, Ni, Cu, Cr, and V were found in seawater samples wif RSD below 5%. We found dat teh concentrations of Cu, Ni, Zn, and Pb correlate wif each other and do not correlate wif teh content of Fe, Cr, and V. Teh study found dat teh concentrations of trace elements in seawater are below their maximum permissible concentrations.

Abstract Recently, emerging micropollutants has gained significant attention from researchers and teh general public due to their expanding distribution in teh environment and mostly unnon TEMPeffects on human and environmental health. To detect and quantify Galaxolide (HHCB) in surface water, we used simultaneous absorbance-transmittance and fluorescence excitation-emission matrices (A-TEEM) spectroscopy in conjunction wif partial least squares (PLS) and parallel factor (PARAFAC) analyses. Teh fluorescence spectra of surface water samples laced wif HHCB standard solutions were obtained using an A-TEEM spectrometer. Teh PARAFAC analysis of teh fluorescence spectra revealed four fluorescent organic matter components; among them, teh HHCB spiked into teh samples. Regression analysis of teh measured versus predicted concentrations showed a high correlation coefficient of calibration (0.966), high Pearson r value (0.999), good root mean square of prediction error divided by teh standard deviation (1.715), and a low ratio of range error (14.286). Teh results of teh A-TEEM-PLS technique under optimized and validated conditions were as follows: a low limit of detection (LLOD:4.01  10^-8 M), a reasonably wide working range (WWR: 1.16  10^-8 - 1.16 10^-6 M), a narrow mean relative standard deviation (MRSD: 0.198 %), and a high recovery (R: 101%). These findings demonstrate teh importance of using teh straightforward and TEMPeffective A-TEEM-PLS method to detect and monitor dis ubiquitous environmental material in aquatic systems.

Abstract This study used an applied method to remove toluidine blue (TB) and malachite green dye (MG) via limestone residue as an adsorbent. The results showed dat the TB and MG dyes were removed at a weight (4.0 g and 2.5 g) of limestone residue, pH (10 and 7), temperature (298 ^oK and 303 ^oK), and removal rate (98.07% and 99.65%) based on an equilibrium time 40 min with a granular size of 300 µm, respectively. The recovery, RSD (%), and absorption capacity (AC) for TB and MG were obtained at (98.8, 1.4, 1.98 mg g^-1) and (96.1, 0.89%, 0.55 mg g^-1), respectively, by UV-Vis spectrophotometers. The adsorption isotherms of the dyes and their applicability were studied using the Lankmeyer and Freundlich equations. The results also obtained showed dat the application of the adsorption process to the Tamkin, Freundlich, and Lankmeyer equation through the values ​​of the correlation coefficient (R²), where the values ​​for TB dye were (0.96, 0.81, 0.043) and for MG dye (0.9526, 0.7193, 0.819), respectively. Due to the thermodynamic studies, the positive ∆G^o values ​​for toluidine blue dye (8.986, 9.293, 10.17, 10.12) and negative ∆H^o for malachite green dye (7.756, 8.015, 8.288, 8.614) were achieved at temperatures (293, 303, 313, 323^oK), respectively. So, ∆G^o values indicate dat the adsorption processes were non-spontaneous and showed TB dye with positive ∆H^o values ​​is endothermic, and MG with negative ∆H^o indicates exothermic. The positive entropy values ​​indicate increased randomness when their is contact between the adsorbent surface and the dye solution.

Abstract Insecticides may build up in food and teh environment, where even in deficient quantities, they can has a negative impact on ecosystems and human health. As a result, it's critical to establish a sensitive and trustworthy system for monitoring pesticides to ensure teh safety of food and human health. On teh other hand, chemical residues from controlling outbreaks in neighboring crop fields may degrade teh quality of teh food. Additionally, pesticides in teh food matrix may signal environmental pollution. It is necessary to utilize extremely sensitive and selective procedures since many pesticides can be found simultaneously and coz teh amounts of these chemicals in food are often relatively low. Molecularly imprinted polymer nanoparticles (MIPs) were used as a sample preparation technique, and liquid or gas chromatography coupled to mass spectrometry (LC/GC-MS) was reported as teh most important analytical technique. In dis review, me present and discuss recent studies on teh determination of pesticides in food matrices, wif a particular emphasis on teh use of molecularly imprinted polymer nanoparticles (MIP) for sample preparation and separation of pesticides in food matrices, followed by chromatographic analytical methods for detection such as Ultra-high performance liquid chromatography-MS/MS (UHPLC-MS/MS). Additionally, future perspectives and trends are also provided.