The inhalation toxicity of two commercial dyes: solvent yellow 33 and solvent green 3

Innovative Sol-gel functionalized polyurethane foam for sustainable water purification and analytical advances

Nanomaterial combined polymeric membranes such as polyurethane foams (PUFs) have garnered enormous attention in the field of water purification due to their ease of management and surface modification, cost-effectiveness, and mechanical, chemical, and thermal properties. Thus, this study reports the use of novel Sol-gel impregnated polyurethane foams (Sol-gel/PUFs) as new dispersive solid phase microextractors (d- µ SPME) for the efficient separation and subsequent spectrophotometric detection of Eosin Y (EY) textile dye in an aqueous solution with a pH of 3-3.8. The Sol gel, PUFs, and Sol gel-impregnated PUFs were characterized using scanning electron microscopy (SEM), goniometry measurements, dynamic light scattering (DLS), energy dispersive spectroscopy (EDS), UV-Visible, and FTIR spectra. Batch experiment results displayed a remarkable removal percentage (96% ± 5.4%) of the EY from the aqueous solution, with the total sorption time not exceeding 60 min. These data indicate rate-limited sorption via diffusion and/or surface complex ion associate formations after the rapid initial sorption steps. A pseudo-second order kinetic model thoroughly explained the sorption kinetics, providing a sorption capacity (qe) of 37.64 mg g-1, a half-life time (t1/2) of 0.8 ± 0.01 min, and intrinsic penetration control dye retention. The thermodynamic results revealed a negative value for ΔG⁰ (-78.07 kJ mol-1 at 293 K), clearly signifying that the dye uptake was spontaneous, as well as a negative value for ΔH⁰ (-69.58 kJ mol-1) and a positive value for ΔS⁰ (147.65 J mol-1 K-1), making clear the exothermic nature of EY adsorption onto the sorbent, with a growth in randomness at the molecular level. A ternary retention mechanism is proposed, involving the "weak base anion exchanger" of {(-CH2-OH+ -CH2-) (Dye anion)-}Sol-gel/PUF and/or {(-NH2 + -COO-) (Dye anion)-}Sol-gel/PUF via solvent extraction and "surface adsorption" of the dye anion on/in the Sol-gel/PUFs membranes in addition to H-bonding, including surface complexation and electrostatic π-π interaction, between the dye and the silicon/zirconium oxide (Si-O-Zr) and siloxane (Si-O-Si) groups on the sorbent. Complete extraction and recovery (93.65 ± 0.2, -102.28 ± 2.01) of EY dye with NaOH (0.5 M) as a proper eluting agent was achieved using a sorbent-packed mini column. In addition, the established extractor displayed excellent reusability and does not require organic solvents for EY enrichment in water samples, making it a talented nominee as a novel sorbent for EY sorption from wastewater. This study is of great consequence for expanding the applicatio1n of Sol-gel/PUFs in developing innovative spectrophotometric sensing strategies for dye determination. In view of this, it would also be remarkable to perform future studies to explore the analytical implications of this extractor regarding safety and environmental and public health issues associated to the pollutant.

Sol-Gel Functionalized Polyurethane Foam-Packed Mini-Column as an Efficient Solid Extractor for the Rapid and Ultra-Trace Detection of Textile Dyes in Water

Textile dyes widely used in industrial products are known as a major threat to human health and water ecological security. On the other hand, sol gel represents a principal driver of the adoption of dispersive solid-phase microextractors (d-µ SPME) for pollutants residues in water. Thus, the current study reports a new and highly rapid and highly efficient hybrid sol-gel-based sponge polyurethane foam as a dispersive solid-phase microextractor (d-µ-SPME) platform packed mini-column for complete preconcentration and subsequent spectrophotometric detection of eosin Y textile dye in wastewater. The unique porous structure of the prepared sol-gel immobilized polyurethane foams (sol-gel/PUF) has suggested its use for the complete removal of eosin Y dye (EY) from water. In the mini-column, the number (N) of plates, the height equivalent to the theoretical plates (HETP), the critical capacity (CC), and the breakthrough capacities (BC) of the hybrid sol-gel-treated polyurethane foams towards EY dye were determined via the breakthrough capacity curve at various flow rates. Under the optimum condition using the matrix match strategy, the linear range of 0.01-5 µg L-1, LODs and LOQs in the range of 0.006 µg L-1, and 0.01 µg L-1 for wastewater were achieved. The intra-day and inter-day precisions were evaluated at two different concentration levels (0.05 and 5 μg L-1 of dye) on the same day and five distinct days, respectively. The analytical utility of the absorbents packed in pulses and mini-columns to extract and recover EY dye was attained by 98.94%. The column could efficiently remove different dyes from real industrial effluents, and hence the sol-gel/PUF is a good competitor for commercial applications. The findings of this research work have strong potential in the future to be used in selecting the most suitable lightweight growing medium for a green roof based on stakeholder requirements. Therefore, this study has provided a convenient pathway for the preparation of compressible and reusable sponge materials from renewable biomass for efficient removal of EY from the water environment.

Green synthesis of zinc oxide nanoparticles loaded on activated carbon prepared from walnut peel extract for the removal of Eosin Y and Erythrosine B dyes from aqueous solution: experimental approaches, kinetics models, and thermodynamic studies

Water contamination due to release of dye containing effluents is one of the environmental problems of serious concern today. The present study investigate the green synthesis of zinc oxide nanoparticles (ZnO-NPs) doped on activated carbon (AC) prepared from walnut peel extract and to estimate its efficiency in the removal of Eosin Y (Eo-Y) and Erythrosine B (Er-B) from its aqueous solution. The synthesized AC-ZnO was identified by field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), and the Brunauer-Emmett-Teller. The influence of various parameters such as pH, dosage of AC-ZnO, contact time, and concentrations of Eo-Y and Er-B was also studied. The pH 3 was observed as the optimum pH while the equilibrium was noticed to reach in 30 min at dosage of 1 g/L and initial concentration 100 mg/L for Eo-Y and Er-B adsorption onto AC-ZnO. The maximum adsorption capacity of Eo-Y and Er-B onto AC-ZnO was found to be 163.9 and 144.92 mg/g (and removal efficiencies of 95.11 and 98.31 %), respectively. The process of Eo-Y and Er-B adsorption on AC-ZnO was observed to be depended on the pseudo-second-order kinetic model which indicates chemisorption processes. Langmuir adsorption isotherm model test described the removal of Eo-Y and Er-B on AC-ZnO. The thermodynamic data indicated that the adsorption was endothermic process. Also, the values, S_BET and V_TOTAL, for the AC-ZnO were equal to 725.65 m²/g and 0.6004 cm³/g, respectively. The results of this study exhibited that AC-ZnO was a very effective method that can be used for the removal of Eo-Y and Er-B from aqueous solutions.

Comparison of the efficiency of Cu and silver nanoparticle loaded on supports for the removal of Eosin Y from aqueous solution: Kinetic and isotherm study

In this study, the efficiency of a novel copper containing ionic liquid based nanoporous organosilica (Cu@IL-ONO) and palladium nanoparticles loaded on activated carbon (Pd-NP-AC) for the removal of Eosin Y from aqueous solution was investigated. The Cu@IL-ONO was prepared by hydrolysis and co-condensation of tetramethoxysilane (TMOS) and 1,3-bis (trimethoxysilylpropyl) imidazolium chloride in the presence of surfactant template following immobilization of copper chloride dihydrate. These materials were characterized by nitrogen adsorption-desorption analysis and scanning electron microscopy (SEM) and subsequently used for the successful removal of Eosin Yellow (EY) from aqueous solution. The effects of pH, contact time, amount of adsorbents, initial dye concentration was optimized and set as following: 0.005g/50mL Cu@IL-ONO and 0.015g/50mL Ag-NP-AC at pH=2 for Cu@IL-ONO and pH=3 for Ag-NP-AC and contact time less than 14min. The experimental removal percentage data at various situations was fitted by conventional isotherm models like Langmuir, Freundlich, Tempkin and Dubinin-Radushkevich (D-R). Judgment based on linear regression coefficient (R(2)) and error analysis show high usability of the Langmuir isotherm for best explanation of experimental data with maximum monolayer adsorption capacities 286 and 250mgg(-1) at room temperatures for Cu@IL-ONO and Ag-NP-AC, respectively. Fitting the corresponding data of removal percentage at various experimental conditions shows the suitability of second order and interparticle diffusion model for interpretation of real data.

Medical Management of the Traumatic Consequences of Civil Unrest Incidents

In the context of this review, civil unrest is defined as disharmony, expressive dissatisfaction and/or disagreement between members of a community, which leads to a situation of competitive aggression that may find expression as disruption of organisation, conflicts, damage to property and injuries. Such a breakdown of harmonious relationships, which may result in property damage and human injuries that may be threatening to life, varies in magnitude from participation of a very few individuals up to the involvement of large crowds of people, which may evolve into a full-scale riot. It is the latter situation often involving demonstrators, opposing groups and law enforcement personnel that can result in multiple casualties and present a very significant challenge to the resources of local healthcare institutions. The causation of civil unrest incidents is multifactorial and has generic, specific and potentiating elements. With the current national and international societal, political and discriminatory problems, it is likely that civil unrest incidents on both small and large scales will continue to occur at a high and possibly increasing rate on a worldwide basis, and for these not infrequent incidents, the medical community should be in a state of informed preparation. The circumstances of civil unrest incidents are very variable with respect to causation, overall magnitude, frequency, timing, geographical location, numbers of persons involved, demographics of participants, influence of extremists, confrontation with opposing groups and control measures used by law enforcement agencies. Methods used by police and security forces for the control of civil unrest incidents, if advanced negotiations with organisers and verbal warnings have failed, fall basically into two categories: physical and chemical measures. Physical methods include restraint holds, truncheons, batons, mounted horses, projectiles (such as bean bags, plastic and rubber bullets), water cannons, tasers and (rarely) live ammunition. All of these physical measures are associated with pain and immobilisation, and there is a high potential for soft tissue and bone injuries. Some of the more severe physical methods, including plastic and rubber bullets, may cause lethal injuries. The basis for using chemicals in civil unrest incidents is that they cause distraction, transient harassment and incapacitation, temporary impairment of the conduct of coordinated tasks and cause a desire to vacate the area of unrest. Although screening smokes and malodors have sometimes been employed, the major group of chemicals used are peripheral chemosensory irritants (PCSIs), which reversibly interact with sensory nerve receptors in exposed skin and mucosal surfaces, resulting in the production of local uncomfortable sensations and associated reflexes. Major effects are on the eye, respiratory tract and (to a lesser degree) skin. Thus, the induced transient pain and discomfort in the eye, respiratory tract and skin, together with associated lacrimation, blepharospasm, rhinorrhoea, sialorrhoea, cough and breathing difficulties, produce temporary incapacitation and interference with the conduct of coordinated tasks, and form the basis for harassment of malefactors. Currently used peripheral chemosensory irritants are 1-chloroacetophenone, 2-chlorobenzylidene malononitrile, dibenz(b.f)-1,4-oxazepine, oleoresin capsicum and pelargonic acid vanillylamide. Depending on operational circumstances, irritants may be dispersed as a smoke, powder cloud, aerosol, vapour, or in solution; the mode of generation and dispersion of irritant can influence hazard. Brief acute exposure to chemosensory irritants produces effects that generally resolve within an hour, leaving no long-term sequelae. However, sustained exposure to high concentrations may produce tissue injury, notably to the eye, respiratory tract and skin. With solutions of sensory irritants, other formulation constituents may enhance PCSI toxicity or introduce additional local and/or systemic toxicity. By the very circumstances of civil unrest incidents, injuries are inevitable, particularly when emotions are heightened and police and security forces have to resort to various chemical and/or physical means of control. Trauma may include slight to severe physical and/or chemical injuries, psychological problems and occasional deaths. Hospitals should be prepared for a wide range of casualties, and the fact that those seeking help will constitute a heterogeneous group, including wide age range, male, female, and individuals with pre-existing ill health. A major civil unrest incident necessitates that the local receiving hospital should be prepared and equipped for decontamination and triage processes. It is necessary to reassure patients who have been exposed to sensory irritants that the signs and symptoms are rapidly reversible, and do not result in long-term sequelae. With respect to chemical exposures, detailed evaluation should be given to possible ocular, cutaneous, respiratory and gastrointestinal effects. Also, exposure to chemosensory irritants results in transient increases in blood pressure, bradycardia and increased intraocular pressure. This indicates that those with cardiovascular diseases and glaucoma may be at increased risk for the development of complications. This article details the pharmacological, toxicological and clinical effects of chemicals used in civil disturbance control and discusses the management of contaminated individuals. Additionally, the potential for adverse effects from delivery systems and other physical restraint procedures is summarised. Due to the emergency and specialised circumstances and conditions of a civil unrest incident, there is a clear need for advanced planning by healthcare institutions in the event that such an incident occurs in their catchment area. This should include ensuring a good information base, preparations for medical and support staff readiness, and availability of required equipment and medications. Ideally, planning, administration and coordination should be undertaken at both local (regional) and central (governmental) centres. Regional centres should have responsibilities for education, training, ensuring facilities and staffing are appropriate, and that adequate equipment and medicines are available. There should be cooperative interactions and communications with local police and other emergency services. Centrally directed functions should include ensuring adequacy of the information base, coordinating activities and agreeing approaches between the regional centres, and periodic audits of regional centres with respect to the staffing, facility, equipment and training needs. Also, there is a need for most countries to introduce detailed guidelines and formal (regulatory) schemes for the assessment of the safety-in-use of chemicals and the delivery systems that are to be used against heterogeneous human populations for the control of civil unrest incidents. Such regulatory approval schemes should also cover advisory functions for safe use and any required restrictions.

Optimal design allocations for estimating area under curves for studies employing destructive sampling

Optimal allocations of experimental resources for the estimation of integrals is considered for experiments that use destructive sampling. Given a set of sampling times, a minimum mean square error rule is given for the allotment of fixed experimental resources to the independent variable. The results are seen to be functionally dependent upon the pattern of underlying variability assumed in the model and upon the quadrature rule used to estimate the integral. Extensions to other optimality criteria, including a minimum mean absolute deviation criterion, and to cases involving multiple treatment groups, are also noted.

A review of the toxicity and carcinogenicity of anthraquinone derivatives

Anthraquinones (AQs) are a group of functionally diverse chemicals structurally related to anthracene. Both natural and synthetic AQs have widespread applications throughout industry and medicine, thereby indirectly and directly exposing the human population. Because of the close similarity in structure between AQs and the toxic analogue, anthracene, there is concern over the potential damage which these compounds may produce. This review summarizes the toxicity and carcinogenicity of synthetically-derived AQs in experimental animals, classified into 3 categories based upon phenolic, amino, or nitro substitution to the AQ ring structure. The effect of chemical substitution in relation to toxicity and carcinogenicity is discussed.

The effect of molecular weight/lipophilicity on clearance of organic compounds from lungs

The objective of this study was to test the hypothesis that lipophilicity (as measured by the octanol/water partition coefficient, P) and/or molecular weight are determining factors in the rate of clearance of organic compounds from the lung. Previous work in our laboratory has shown that organic-soluble compounds such as pyrene, benzo[a]pyrene, 1-nitropyrene, 2-aminoanthracene, phenanthridone, dibenzo[c,g]carbazole, 1,3-dichloropropene, and methyl bromide, all of which have a log P less than 6.1, clear the lung rapidly (t 1/2 less than 12 hr). In the present study, organic compounds (mainly anthraquinone dyes) having a wider range of log P's (1.95-8.65) were instilled into rat lungs and the percentage of the compound retained in the lungs at 24 hr was determined. A positive correlation between the log of the theoretical P and the percentage of the compound retained in lungs at 24 hr was found. The lipophilicity of the series of compounds studied was highly dependent on the molecular weight, so that there was also a positive correlation between the molecular weight of the compounds and the percentage of the compound retained in the lung at 24 hr. To help understand the relative importance of lipophilicity and molecular weight in determining lung retention, an additional compound with a high molecular weight but containing a polar functional group [1,5-di(2-sulfo-p-toluidino)anthraquinone] was studied. The results indicated that the lipophilicity was the more important factor in whether the material was retained in the lung. On the basis of the results of this study, organic-soluble compounds with molecular weights less than 300 Da can be expected to clear the lungs rapidly. Nonpolar, organic-soluble compounds with a molecular weight greater than 300 Da can be expected to clear the lungs more slowly.

Testing for the equality of area under the curves when using destructive measurement techniques

The area under a curve (AUC) of metabolite concentration or drug concentration over time has biological meaning in many situations, and the test of AUC equality among a set of different dosing regimens is often of interest. For the situation where the experimental unit must be sacrificed in order to obtain an estimate of the metabolite or drug concentration, it is noted that linear combinations of mean concentrations at time points for a particular dosing regimen can be used to estimate the AUC for that regimen. Contrasts among AUC estimates are readily constructed and tested within this derivation.