Efficacy of removal of CCL viruses under enhanced coagulation conditions

The focus of coagulation as a water treatment process is shifting to accommodate recent regulatory additions that strive to balance the risks between microbial and chemical contamination of drinking water. In this work, enhanced coagulation using increased ferric chloride dose and/or pH adjustment was evaluated for removal efficacy of viruses on the United States Environmental Protection Agency (USEPA) Contaminant Candidate List (CCL), their surrogates, and dissolved organic carbon (DOC). Jar tests demonstrated that optimal DOC removal was achieved using 40 mg/L FeCl3 at a pH between 5 and 6. Under these conditions, bench-scale testing resulted in a maximum removal of 2.58 log units of adenovirus type 4, 2.50 log units of feline calicivirus, 2.32 log units of MS2, 1.75 log units of PRD1, 1.52 log units of phi-X174, 2.49 log units of fr, and 56% of DOC. The trend in virus removals (MS2 and fr > PRD1 and phi-X174) was consistent between bench- and pilot-scale testing; however, pilot-plant removals exceeded bench-scale removals. Feline calicivirus was more efficiently removed than the bacteriophages, thereby suggesting potential for the bacteriophages as suitable surrogates, with MS2 and fr being more representative and PRD1 and phi-X174 (which were removed to a lesser extent) more conservative. The bacteriophages do not appear to be appropriate surrogates for adenovirus.     

Production of lipophilic volatile organohalogen materials during laboratory chlorination of some waste water and polluted river water samples from Yugoslavia

Water chlorination leads to the generation of various halogenated products of natural and waste water organic mater. In natural surface water humic matter usually makes the greatest part of the total organic matter. However, in the river water polluted with various organic wastes, other organic matter is also present in significant concentrations. The investigation of the relationship between the concentration of organic matter in the samples of waste water and heavily polluted river waters in Yugoslavia on one side, and the production of the lipophilic volatile organohalogen materials during the process of their chlorination on the other side is described. The production of the halomethanes and other ECD response materials during the chlorination of water samples in laboratory conditions is compared with the concentrations of organic materials in water samples. From the obtained linear correlation coefficients, possibilities of predicting amounts of organohalides during the chlorination process by using several very simple methods for the organic materials estimation in the investigated water samples are discussed and compared.     

Treatment responsivity of cocaine-dependent patients with antisocial personality disorder to cognitive-behavioral and contingency management interventions.

This study compared the efficacy of 2 approaches for the treatment of cocaine dependence among methadone-maintained patients with and without antisocial personality disorder (ASPD). Patients were randomly assigned to 4 study conditions: cognitive-behavioral treatment (CBT), contingency management (CM), CBT with CM, or methadone maintenance. The Structural Clinical Interview for Mental Disorders-IV was administered to 108 patients to assess ASPD. A 2-way analysis of variance showed that patients with ASPD were more likely to abstain from cocaine use during treatment than patients without ASPD. The strong treatment effect for ASPD patients was primarily due to the CM condition. Regression analyses showed that ASPD remained significantly related to CM treatment responsivity while controlling for other factors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Chlorine and ozone disinfection of Encephalitozoon intestinalis spores

Microsporidia are intracellular eukaryotic parasites which have the potential for zoonotic and environmental, including waterborne, transmission. Encephalitozoon intestinalis is a microsporidian pathogen of humans and animals and has been detected in surface water. It is also on the Contaminant Candidate List of potential emerging waterborne pathogens for the US EPA. We performed disinfection studies using chlorine and ozone on E. intestinalis spores with a cell-culture most-probable-number assay to determine infectivity. Chlorine experiments were performed at 5 degrees C at pH of 6, 7, and 8 with 1mg/L initial chlorine concentrations, while ozone experiments were performed at 5 degrees C and pH 7 with initial ozone doses of 1 and 0.5mg/L, both in buffered water. A derivation of Hom's model for disinfection kinetics under dynamic disinfectant concentrations was used to fit observed data and calculate concentration-time product (C*t) values. Chlorine C*t values varied with pH such that 99% (2-log(10)) C*t ranged from 12.8 at pH 6 to 68.8 at pH 8 (mg min/L). Ozone C*t values were approximately an order of magnitude less at 0.59--0.84 mg min/L, depending on initial concentration.     

Mercury distribution in a polluted marine area, ratio of total mercury, methyl mercury and selenium in sediments, mussels and fish

Total mercury, methyl mercury and selenium concentrations were determined in sediments and organisms from the Kaštela bay in the Central Adriatic, polluted with inorganic mercury by a chlor-alkali plant. Sediments and mussels (Mytilus galloprovincialis) contained high total mercury concentrations, especially in the vicinity of the source of pollution. The percentage of mercury in the methyl form increased from surface sediments (up to 1.37%) to the edible parts of mussels (0.1–27%, negatively correlated with total mercury concentrations) and to the fish, in which methyl mercury accounted for most of the mercury in the muscle tissue.     

Influence of carboxymethylation on the surface physical–chemical properties of glucuronoxylan and arabinoxylan films

Xylans were carboxymethylated in order to increase their anionic nature and thus tune their surface free energy (SFE) and hydrophilicity, which are of crucial importance in the majority of special applications. Fourier transform infrared spectroscopy and polyelectrolyte titration results confirmed the successful carboxymethylation of the xylan samples. The main aim of this study was to investigate the influences of carboxymethylation of glucuronoxylan and arabinoxylans on the surface physical and chemical properties of the films made from them. Films were prepared by the casting method, and their surface morphologies were analyzed by atomic force microscopy. The surface chemical compositions of the films were investigated using X‐ray photoelectron spectroscopy, and their influences on SFE, i.e., Lifshitz–van der Waals and electron donor and acceptor contributions, were determined using goniometry. The introduction of ～2 mmol/g of carboxyl groups into the glucuronoxylan or arabinoxylan molecular structures had a significant influence on the chemical and physical surface properties of the prepared films. Higher amounts of the carboxyl group present on the films' surfaces and higher surface roughness contributed to a significant increase (by 270%) in the electron donor component of SFE and to 40% improvements in the hydrophilicities of the films' surfaces. POLYM. ENG. SCI., 55:2706–2713, 2015. © 2015 Society of Plastics Engineers     

Isolation and identification of Di-D-fructose dianhydrides resulting from heat-induced degradation of inulin

Dry heating of inulin up to 200 °C for 30 min resulted in a wide range of degradation products, from which five quantitatively dominating compounds were isolated using flash chromatography and semi-preparative HPLC–RI. It was possible to identify four different DFDAs (di-d-fructose dianhydrides) by means of one- and two-dimensional NMR, namely DFA III (α-D-Fruf-1,2′:2,3′-β-D-Fruf), DFA I (α-D-Fruf-1,2′;2,1′-β-D-Fruf), DFA VII (α-D-Fruf-1,2′;2,1′-α-D-Fruf), and β-D-Fruf-1,2′;2,1′-β-D-Fruf. For the fifth compound, the structure of the difructan α-D-Fruf-1,2′-β-D-Fruf was proposed. Using high-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC–PAD), it was possible to quantify those isolated DFDAs in inulin caramels to a total amount of up to 25%, indicating that dry heating of inulin may be a suitable tool to enrich caramels with DFDAs.     

Mercury distribution in a polluted marine area. Concentrations of methyl mercury in sediments and some marine organisms

Methyl mercury concentrations were measured in various parts of Kastela Bay in the Central Adriatic, which is polluted with inorganic mercury. The values obtained, on a wet weight basis, for sediments were from 2 to 20 micrograms methyl mercury kg-1; for the mussel Mytilus galloprovincialis from 10 to 110 micrograms kg-1; and for various species of fish from 102 to 1448 micrograms kg-1. The methyl mercury content increases by three orders of magnitude going from sediment to fish. The distribution of methyl mercury in relation to the depth of the sediment and the different organs of the mussel is presented. On the basis of the results obtained, it may be concluded that non-migratory species of fish are more suitable for methyl mercury monitoring in the marine environment than are sediment and mussels.     

Levels and long-term trends of polychlorinated biphenyls and DDT''s in mussels collected from the Eastern Adriatic coastal waters

It is well documented that synthetic chlorinated hydrocarbon residues are widespread through the oceanic ecosystem. The Adriatic Sea, as a semi-enclosed body of water, is of special interest for an evaluation of the entry, extent and fate of the pollution by chlorinated hydrocarbons. An investigation of levels of chlorinated hydrocarbons in mussels in the eastern Adriatic coastal waters, off Croatia was performed. Samples were collected between 1972 and 1992 at a large number of stations. All these samples were analyzed by a single analytical group (mostly by the same analyst), using a uniform methodology which inter calibrated during seven international inter-calibration exercises. Mass fractions of chlorinated insecticides and polychlorinated biphenyls in mussels ranged from ND (<0.1) to 107.3 for DDT's and from ND (<0.5) to 1072 × 10⁹ wet weight for PCBs and from 19 to 35,600 for DDT's and from 52 to 103.000 × 10⁹ on an extracted organic matter basis. Averages and ranges of chlorinated hydrocarbons mass fractions in mussels from the Adriatic are compared with the data of mussels obtained in other Mediterranean areas. In all four investigated areas of the Mediterranean (II, IV, VI, and VIII) DDT total mass fractions in mussel are higher than those for the Adriatic. In areas (II, IV, and VIII) the PCB values are higher compared to the Adriatic. Linear regression analysis of pollutant mass fractions in the mussel samples from the eastern Adriatic coastal waters collected during the 20-year period with the years of collection show that a statistically significant negative correlation coefficient is obtained by comparing the values of total DDT mass fractions. For PCBs, a slight negative correlation coefficient is obtained but it is not statistically significant. In the Pula area this correlation coefficient is positive, but it is also statistically non-significant.