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A new method for the direct synthesis of ?-chloro-N?- tosylamidines from olefins using chloramine-T and trifluoromethanesulfonic acid is described. � Georg Thieme Verlag Stuttgart - New York.

A new approach of using free-ammonia measurements as the basis of a control strategy to optimise a chloraminated water distribution system was tested in a laboratory evaluation. A test rig with a newly developed low level on-line free-ammonia analyser was constructed to investigate two different control configurations, the currently used feedback and the proposed feedforward. The results of this trial showed that only using the free-ammonia analyser for feedback control is not ideal due to its inability to detect chlorine overdosing situations. Better results regarding the maximum yield of disinfectant residuals when using the feedforward configuration were observed, and free-ammonia concentrations below 0.065 mg/L were consistently achieved. Refereed/Peer-reviewed

Inactivation of MS2 coliphage by sequential ultraviolet (UV) light/free chlorine exposure, sequential UV light/monochloramine exposure, simultaneous UV light/free chlorine exposure, and simultaneous UV light/monochloramine exposure using either low-pressure (LP) or medium-pressure (MP) UV lamps was evaluated in this study. At a UV dose of 51 mJ/cm2, the sequential exposure to UV or the simultaneous exposure in the primary disinfection stage enhanced MS2 inactivation rates during the secondary disinfection stage by chlorine by 1.5–2.7 times, compared to the rates solely by free chlorine. At the same dose, the sequential exposure to UV or the simultaneous exposure in the primary disinfection stage enhanced MS2 inactivation rates during the secondary disinfection stage by monochloramine by four to five times. The enhancement was similar with the different UV lamps but less significant with a UV dose of 17 mJ/cm2, while the enhancement from the sequential exposure was higher than that after the simultaneous e...

Distribution system monitoring programs typically do not include viral indicators. Coliphages are bacterial viruses that infect Escherichia coli and are used as indicators for human enteric viruses. A study of the Iowa-American Water Company distribution system in Davenport, Iowa, attempted to demonstrate the benefit of coliphage monitoring and suggested that these organisms may be effective indicators of distribution system integrity for contamination resulting from main breaks. Coliphages are particularly well-suited for detecting viral intrusion in chloraminated systems because of their resistance to chloramines.

Objectives: Chloramines, which are produced by the reaction of chlorine with the organic matter present in indoor pools, are potential airway irritants in swimmers. The objective of this study was to compare the prevalence of health complaints of young swimmers and young indoor soccer players and to evaluate the relationship between chloramine concentrations and the athletes’ health complaints. Methods: Health complaints were first (Part 1) documented by questionnaire in 305 competitive swimmers and 499 indoor soccer players of the Quebec City region (Canada). Then, (Part 2) health complaints were documented during five training sessions in 72 competitive swimmers in comparison to 73 soccer players. The chloramines in the swimming pool air and water were measured as well as the peak expiratory flow (PEF) before and after the training session. Results: In Part 1, the swimmers reported more lower (adjusted OR: 1.5; IC95%= 1.0–2.2) and upper respiratory symptoms (adjusted OR: 3.7; IC95%= 2.4–5.8). In Part 2, the swimmers experienced more frequent lower (adjusted OR: 3.5; IC95%= 2.0–6.0) and upper respiratory symptoms (adjusted OR: 3.1; IC95%= 1.8–5.4). Overall, swimmers exposed to the highest levels of chloramines in the air and water had more respiratory complaints. Conclusions: Swimmers exposed to chlorination by-products in both the water and air of indoor swimming pools experience frequent respiratory symptoms that could potentially be reduced by limiting exposure to these products.

Synthesis and radioiodination of some 9-aminoacridine derivatives for potential use in radionuclide therapy

A switch from free chlorine to chloramine disinfectant triggered problems with excessive lead in Washington, D.C., drinking water. High levels of lead originated in the service lines, but excessive lead was also derived from solder or brass plumbing materials. In many cases, the highest lead concentrations emerged from the tap after about 1 min of flushing-a troublesome outcome, given that routine public notification recommended that consumers flush for about a minute to minimize lead exposure. Bench-scale testing found that chlorine reacts with soluble Pb +2 to rapidly precipitate a red-brown-colored lead solid that was insoluble even at pH 1.9 for 12 weeks; this solid did not form in the presence of chloramine. Further experiments indicated that chloramines sometimes dramatically worsened lead leaching from brass relative to free chlorine, whereas new lead pipe was not strongly affected.

Bench-scale experiments determined the inactivation rates of adenovirus serotype 2 with low-pressure, high-output ultraviolet (UV) light, chlorine (Cl 2 ), and preformed chloramines. Studies with sequential chloramines were also done to mimic water treatment practices. Sequential experiments with adenovirus serotype 2 suspended in laboratory-grade water and natural waters containing ammonia were exposed to either UV light followed by Cl 2 /chloramines or the reverse sequence. Adenovirus log reductions were quantified through cell culture techniques. A free Cl 2 C × T (concentration x time) of 1.22 mg-min/L resulted in a 3.72-log reduction, a preformed chloramine C x T of 264.5 mg-min/L resulted in a 1.2-log reduction, a sequential chloramine C x Tof 40.5 mg-min/L resulted in a 1-log reduction, and a UV dose of 40 mJ/cm 2 resulted in a 1-log reduction. Up to 4-log reductions were achieved with a UV dose of 40 mJ/cm 2 followed by a sequential chloramine C × T of 27.2 mg-min/L. This suggests that sequential disinfection may be the best option for dealing with UV-resistant organisms such as adenoviruses.

A sensitive and selective spectrophotometric method has been developed for the determination of six phenothiazine neuroleptics. The method is based on the interaction of the drugs with chloramine-T in sulphuric acid medium to yield a red, reddish-violet, orange or greenish-blue intermediate with maximum absorption at 500-636 nm. Beer's law is obeyed over the range 5-125 μg ml−1 of the drugs. The apparent molar absorptivities were found to be in the range 1.04x103 to 5.46x103 1.mol−1cm−1. The investigated drugs were assayed in tablets and injections. The mean percentage recoveries were 97.65-101.75 and the relative standard deviations were found to be less than 2%.

Resume Un maitre-nageur de 44 ans, non allergique, employe d'une piscine publique, presente depuis six ans une rhinosinusite et des migraines chaque jour de travail. Les symptomes disparaissent les jours de vacances permettant de suspecter une origine professionnelle. L'enquete professionnelle realisee par le medecin du travail montre que le sujet est expose a divers produits de desinfection de l'eau, notamment le chlorure de benzalkonium, le chlore libre et une chloramine. Les taux de ces elements mesures dans l'atmosphere du lieu de travail restent en dessous des normes limites admises. Les investigations sont en cours lorsque la modification du Tableau 66 intervient et permet de declarer une maladie professionnelle sans recours a de multiples tests. La chloramine parait le premier agent responsable. Les mecanismes physiopathologiques sont discutes ainsi que les modifications importantes du Tableau 66 avec leurs consequences pratiques.

Biofilm in drinking water systems is undesirable. Free chlorine and monochloramine are commonly used as secondary drinking water disinfectants, but monochloramine is perceived to penetrate biofilm better than free chlorine. However, this hypothesis remains unconfirmed by direct biofilm monochloramine measurement. This study compared free chlorine and monochloramine biofilm penetration into an undefined mixed-culture nitrifying biofilm by use of microelectrodes and assessed the subsequent effect on biofilm activity and viability by use of dissolved oxygen (DO) microelectrodes and confocal laser scanning microscopy (CLSM) with LIVE/DEAD BacLight. For equivalent chlorine concentrations, monochloramine initially penetrated biofilm 170 times faster than free chlorine, and even after subsequent application to a monochloramine penetrated biofilm, free chlorine penetration was limited. DO profiles paralleled monochloramine profiles, providing evidence that either the biofilm was inactivated with monochloramine's penetration or its persistence reduced available substrate (free ammonia). While this research clearly demonstrated monochloramine's greater penetration, this penetration did not necessarily translate to immediate viability loss. Even though free chlorine's penetration was limited compared to that of monochloramine, it more effectively (on a cell membrane integrity basis) inactivated microorganisms near the biofilm surface. Limited free chlorine penetration has implications when converting to free chlorine in full-scale chloraminated systems in response to nitrification episodes.

T ... ma Bra bewlicial for control of Legionella in plumbing9MM"s major appeal. Because monochloramine chlorine penetrates biofilms better than free chlorine, the hypothesis that chloramines are more effective in the biological niche of Legionella is biologically plausible. Investigators from the Centers for Disease Control and Prevention (CDC) presented a study in the September 2000 issue of Journal AWWA concluding that the use of monochloramine for disinfection of municipal water might prevent Legionnaires' disease.1 These authors suggested that 90 percent of hospital-acquired outbreaks of Legionnaires' disease associated with drinking water might not have occurred if monochloramine had been used instead of free chlorine for residual disinfection.1

The primary focus of this paper is to elucidate the influence of mixtures of natural organic matter (NOM) and free chlorine and NOM and monochloramine on the reduction of PbO2 in drinking water. Parallel experiments using PbO2 particles of two different sizes (approximately 20 and approximately 200 nm) were conducted to explore the effects of particle size on this process. In the absence of NOM, reduction of PbO2 was observed in monochloramine solutions but not in free chlorine solutions. In the presence of NOM, significant Pb(II) formation was observed in disinfectant-free solutions. The release of Pb(II) was suppressed by the additional presence of free chlorine until the point in time when free chlorine was exhausted. Monochloramine also repressed Pb(II) formation in the presence of NOM but not as significantly as free chlorine. The presence of NOM and monochloramine does not necessarily act additively or synergistically due to complex interactions including reduction of PbO2 by NOM, monochloramine mediated reduction of PbO2, and oxidation of NOM by monochloramine. Higher surface area-normalized Pb(ll) formation was found in experiments using larger PbO2 particles. The high reactivity generally associated with nanoparticles was not observed in our study.

The formation of disinfection by-products (DBPs) from chlorination and monochloramination of treated drinking waters was determined. Samples were collected after treatment at 11 water treatment works but before exposure to chlorine or monochloramine. Formation potential tests were carried out to determine the DBPs formed by chlorination and monochloramination. DBPs measured were trihalomethanes (THMs), haloacetic acids (HAAs), halonitromethanes (HNMs), haloacetonitriles (HANs), haloaldehydes (HAs), haloketones (HKs) and iodo-THMs (i-THMs). All waters had the potential to form significant levels of all the DBPs measured. Compared to chlorine, monochloramination generally resulted in lower concentrations of DBPs with the exception of 1,1-dichloropropanone. The concentrations of THMs correlated well with the HAAs formed. The impact of bromine on the speciation of the DBPs was determined. The literature findings that higher bromide levels lead to higher concentrations of brominated DBPS were confirmed.

For producing antibacterial textiles, the conventional finishing processes have high productivity and low processing costs, but textiles finished in these ways exhibit low durability against laundering. Therefore, cotton fabrics were bleached with hydrogen peroxide, finished with triclosan, and then treated with polycarboxylic acids such as 1,2,3,4-butanetetracarboxylic acid (BTCA) and citric acid (CA) as crosslinking agents to provide durable antibacterial properties. The surface of fibers treated with BTCA had a greater crosslinked area, and the surfaces of fabrics treated with CA were exposed to greater amounts of deformation due to the mechanical and chemical influences after 50 launderings. The bleaching and finishing treatments did not dramatically affect the breaking strength. However, the polycarboxylic acid treatment (both BTCA and CA) alone showed reductions in the breaking strength when the acid concentration was increased. The polycarboxylic acids were fairly effective against both bacteria, even at lower concentrations, when they were applied to stand-alone cotton fabrics, whereas the antibacterial activity decreased somewhat after the use of polycarboxylic acid and triclosan in the same recipes. Adding polycarboxylic acids to the antibacterial finishing recipes enhanced the durability after 50 launderings, and the durability of the recipes containing BTCA was much higher than that of the recipes containing CA. (c) 2008 Wiley Periodicals, Inc. J Appl Polym Sci 111: 1.3441352, 2009

The triclosan has been applied on cotton fabrics as an antibacterial agent and its durability to repeated home laundering studied. To evaluate the effects of environmental conditions on activity of triclosan, the samples were exposed to acidic, basic and synthetic urine solutions as simulated wearing conditions. The antibacterial activity of fabrics was evaluated against S. aureus and E. coli. The results show that the raw fabrics have the lowest activity and the bleaching pretreatment causes the increase in antibacterial activity and significant reduction in bacteria growth. However, the fabrics show the best activity after finishing with triclosan, especially against S. aureus. It is also observed that the repeated home laundering, and acidic, basic and urine conditions cause the decrease in the activity.

This study investigated the possibility of a statistical model application for the prediction of N -nitrosodimethylamine (NDMA) formation. The NDMA formation was studied as a function of monochloramine concentration (0.001–5 mM) at fixed dimethylamine (DMA) concentrations of 0.01 mM or 0.05 mM. Excellent linear correlations were observed between the molar ratio of monochloramine to DMA and the NDMA formation on a log scale at pH 7 and 8. When a developed prediction equation was applied to a previously reported study, a good result was obtained. The statistical model appears to predict adequately NDMA concentrations if other NDMA precursors are excluded. Using the predictive tool, a simple and approximate calculation of NDMA formation can be obtained in drinking water systems.

The effects of environmental conditions on the antibacterial activity of finished single jersey-knitted cotton fabric have been studied. The fabrics were bleached, finished separately with antibacterial chemicals, and subsequently exposed to chemical solutions that simulated use and wear. The resulting antibacterial activities were evaluated against S. aureus and E. coli bacteria using AATCC Test Method 100-1999. Bleaching and antibacterial finishing led to significant reductions in bacterial growth. The leaching (control led-release) antibacterial mechanism was found to be more effective than the non-leaching mechanism on the respectively finished cotton fabrics. The finished bleached fabrics maintained good antibacterial activity against S. aureus even after the fabrics were exposed to urine.

Environmentally benign HPA is found to be an efficient catalyst for aziridination of olefins in the presence of inexpensive Chloramine-T as a nitrogen source: instantaneous at room temperature, requires only stoichiometric amount of olefin and no allyl amine side product.

The kinetics of chlorine isotope exchange between chloramine-B /CAB/ and chloride has been studied using ion-exchange separation and tracer technique. McKay's plot are linear. The exchange reaction is fast in acidic medium, very slow in neutral medium and does not take place in alkaline medium. In the acidic range the exchange is maximum at pH 3.3. The rate of exchange decreases at pH >3.3 and 5. Addition of neutral salt or parent compound has no effect on the rate of exchange. Activation energy and activation entropy for this exchange reaction have been calculated. ? 1989 Akad�miai Kiad�.

Hydrogen sulphide at trace level can be determined by radiorelease technique using radiochloramine-T. The minimum detection level is 0.25 ppm. Zinc acetate is used to fix H2S from air samples. CS2 does not interfere. Interference by SO2 can be eliminated by oxidizing it with H2O2. ? 1989 Akad�miai Kiad�.