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• Integration of silver nanoparticles and zinc oxide nanowires for antimicrobial applications. • Covalently bonded silver nanoparticles on polyvinylchloride. • Zinc oxide nanowires with a radiating acicular structure. • Significant in vitro antimicrobial efficacy against S. aureus over 24 h. Catheter-associated urinary tract infection is among the most common types of infections in the United States. One of the potential solutions is to modify the catheter surface with antimicrobial agents to prevent bacterial attachment and biofilm formation. In this study, silver nanoparticles were covalently-bonded on polyvinylchloride (PVC) film, and zinc oxide nanowires with a radiating acicular structure were then self-assembled on the composite surface. The composite film reduced the attachment of Staphylococcus aureus by nearly two orders of magnitude in 24 h. The integration of silver nanoparticles and zinc oxide nanowires holds potential for antimicrobial applications. [ABSTRACT FROM AUTHOR]

The article focuses on several patents related to elastomers and plastics in the U.S. Patents discussed include a reinforced polyvinyl chloride (PVC) toughening masterbatch invented by Niu Hongmei and Yan Lanying, high-purity heterophasic propylene copolymers invented by Christelle Grein and Torvald Vestberg; and process for producing functionalized polymer invented by Yong Yang and Jay L. Reimers.

Purpose: Diisononyl phthalate (DiNP) is primarily used as a plasticizer in polyvinyl chloride (PVC) materials. While information is available on general population exposure to DiNP, occupational exposure data are lacking. We present DiNP metabolite urinary concentrations in PVC processing workers, estimate DiNP daily intake for these workers, and compare worker estimates to other populations. Methods: We assessed DiNP exposure in participants from two companies that manufactured PVC materials, a PVC film manufacturer ( n = 25) and a PVC custom compounder ( n = 12). A mid-shift and end-shift urine sample was collected from each participant and analyzed for the DiNP metabolite mono(carboxy-isooctyl) phthalate (MCiOP). Mixed models were used to assess the effect on MCiOP concentrations of a worker being assigned to (1) a task using DiNP and (2) a shift where DiNP was used. A simple pharmacokinetic model was used to estimate DiNP daily intake from the MCiOP concentrations. Results: Creatinine-adjusted MCiOP urinary concentrations ranged from 0.42-80 μg/g in PVC film and from 1.11-13.4 μg/g in PVC compounding. PVC film participants who worked on a task using DiNP ( n = 7) had the highest MCiOP geometric mean (GM) end-shift concentration (25.2 μg/g), followed by participants who worked on a shift where DiNP was used ( n = 11) (17.7 μg/g) as compared to participants with no task (2.92 μg/g) or shift (2.08 μg/g) exposure to DiNP. The GM end-shift MCiOP concentration in PVC compounding participants (4.80 μg/g) was comparable to PVC film participants with no task or shift exposure to DiNP. Because no PVC compounding participants were assigned to tasks using DINP on the day sampled, DiNP exposure in this company may be underestimated. The highest DiNP intake estimate was 26 μg/kg/day. Conclusion: Occupational exposure to DiNP associated with PVC film manufacturing tasks were substantially higher (sixfold to tenfold) than adult general population exposures; however, all daily intake estimates were less than 25% of current United States or European acceptable or tolerable daily intake estimates. Further characterization of DiNP occupational exposures in other industries is recommended. [ABSTRACT FROM AUTHOR]

Abstract: Municipal biosolids are in widespread use as additives to agricultural soils in the United States. Although it is well known that digested sewage sludge is laden with organic wastewater contaminants, the fate and behavior of micropollutants in biosolids-amended agricultural soils remain unclear. An outdoor mesocosm study was conducted in Baltimore, Maryland, to explore the fate of 72 pharmaceuticals and personal care products (PPCPs) over the course of three years in that were placed in plastic containers made from polyvinylchloride and kept exposed to ambient outdoor conditions. Of the 72 PPCPs tested for using EPA Method 1694, 15 were initially detected in the soil/biosolids mixtures at concentrations ranging from low parts-per-billion to parts-per-million levels. The antimicrobials triclocarban and triclosan showed the highest initial concentrations at 2715 and 1265 μg kg−1, respectively. Compounds showing no discernable loss over three years of monitoring included diphenhydramine, fluoxetine, thiabendazole and triclocarban. The following half-life estimates were obtained for compounds showing first-order loss rates: azithromycin (408–990 d) carbamazepine (462–533 d), ciprofloxacin (1155–3466 d), doxycycline (533–578 d), 4-epitetracycline (630 d), gemfibrozil (224–231 d), norfloxacin (990–1386 d), tetracycline (578 d), and triclosan (182–193 d). Consistent with other outdoor degradation studies, chemical half-lives determined empirically exceeded those reported from laboratory studies or predicted from fate models. Study results suggest that PPCPs shown in the laboratory to be readily biotransformable can persist in soils for extended periods of time when applied in biosolids. This study provides the first experimental data on the persistence in biosolids-amended soils for ciprofloxacin, diphenhydramine, doxycycline, 4-epitetracycline, gemfibrozil, miconazole, norfloxacin, ofloxacin, and thiabendazole. [Copyright &y& Elsevier]

Fresh meat retail cases in 104 supermarkets across 5 regions of the United States were audited for the use of packaging types and materials, branding, and cooking/nutritional information. Frequency means were separated for species of beef, ground beef, pork, chicken, turkey, lamb, and veal. Traditional polyvinyl chloride overwrap was used on 47.0% of packages in the fresh meat case nationwide and was the most frequent packaging type for beef, ground beef, pork, lamb, and veal. The use of modified atmosphere packaging was greatest (P < 0.001) in ground beef (33.2%) and turkey (45.1%) products. The 3 most common tray colors in the fresh meat retail case on a national level were white (39.6%), yellow (22.4%), and black (11.5%). Foam trays were used in 72.6% of all packages in the retail meat case. In 2004, 60.2% of all packages were case-ready. Chicken (94.8%) and turkey (95.6%) products utilized case-ready packaging systems more (P < 0.001) than any other species. On a national level, 50.1% of all products carried a national brand, 12.2% carried a store brand, and the remaining 37.7% of products in the fresh meat case in 2004 were not branded. Chicken was most (P < 0.001) likely to carry a natural brand label. Labels with cooking instructions were found most (P < 0.001) on pork (37.3%) and turkey products (48.1%). Chicken (20.4%) and turkey products (20.7%) were most (P < 0.001) likely to have the cooking instructions printed on the packaging material compared with all other species. Labels with nutritional information were most (P <0.001) likely to be found on turkey products (55.7%) in the fresh meat case compared with any other species. On the national level, 6.1% of all packages reported in the fresh meat case in 2004 were value-added. [ABSTRACT FROM AUTHOR]

The article focuses on polyvinyl chloride (PVC) pipe as a solution to address challenges and cost of aging water infrastructure crisis for waste and wastewater systems. It says that underground water infrastructures installed by U.S. government since 1800 until post 1945 soon will all start to fail due to corrosion and inadequate design and installation. It tells that PVC is considered as an effective product that is a bacteria-resistant material and which help maintain water quality.

It has become generally accepted that water quality can deteriorate in a distribution system through microbiological and chemical reactions in the bulk phase and/or at the pipe wall. The most serious aspect of water quality deterioration in a network is the loss of the disinfectant residual that can weaken the barrier against microbial contamination. Studies have suggested that one factor contributing to the loss of disinfectant residuals is the reaction between bulk-phase disinfectants and pipe wall material. Free chlorine loss in corroded metal and polyvinyl chloride (PVC) pipes, subject to changes in velocity, was assessed during an experiment conducted under controlled conditions in a specially constructed pipe loop at the US Environmental Protection Agency's test and evaluation facility in Cincinnati, Ohio. These studies demonstrated that in older unlined metal pipes, the loss of chlorine residual increases with velocity but that wall demand in PVC was negligible. [ABSTRACT FROM AUTHOR]

The main objective of this study was to monitor the volatile organic compounds (VOCs) in the stack gas released from organic chemical industrial plants to determine emission factors. Samples from 52 stacks, with or without air pollution control devices (APCDs), from seven industrial processes were taken and VOCs measured using U.S. Environmental Protection Agency (EPA) Method 18. These 7 processes, including 26 plants, were the manufacturers of acrylonitrile-butadiene-styrene (ABS), polyvinyl chloride (PVC), polystyrene (PS), acrylic resin (ACR), vinyl chloride (VC), para-terephthalic acid (PTA), and synthetic fiber (SYF). The results clearly indicate significant variations of emission factors among the various industrial processes, particularly emission factors for those without APCDs. As expected, those with APCDs yield much less emission factors. Regardless of those with or without APCDs, the order of manufacturing processes with regard to VOC emission factors is SYF > ABS > PS >ACR > PTA > PVC > VC. The emission factors for some processes also differ from those in EPA-42 data file. The VOC profiles further indicate that some VOCs are not listed in the U.S. VOC/Particulate Matter Speciation Data System (SPECIATE). The potential O3 formation is determined from the total amount of VOC emitted for each of seven processes. The resultant O3 yield varied from 0.22 (ACR) to 2.33 g O3 g-1 VOC (PTA). The significance of this O3 yield is discussed. [ABSTRACT FROM AUTHOR]

When the U.S. Environmental Protection Agency (EPA) finalized its 2000 update of the toxicological effects of vinyl chloride (VC), it was concerned with two issues: the classification of VC as a carcinogen and the numerical estimate of its potency. In this commentary we describe how the U.S. EPA review of VC toxicology, which was drafted with substantial input from the chemical industry, weakened safeguards on both points. First, the assessment downplays risks from all cancer sites other than the liver. Second, the estimate of cancer potency was reduced 10-fold from values previously used for environmental decision making, a finding that reduces the cost and extent of pollution reduction and cleanup measures. We suggest that this assessment reflects discredited scientific practices and recommend that the U.S. EPA reverse its trend toward ever-increasing collaborations with the regulated industries when generating scientific reviews and risk assessments. [ABSTRACT FROM AUTHOR]

The article reports on the author's review of internal correspondence, findings, and memos of the Manufacturing Chemists Association, the trade organization for the chemical industry in the U.S. Their action was greatly influenced by the request of the members of a law firm who were involved in a personal liability suit in behalf of a worker who was afflicted with angiosarcoma of the liver, a kind of cancer that affects workers who are exposed to polyvinyl chloride monomer. The documents which they reviewed formed two chapters of their book "Deceit and Denial: The Deadly Politics of Industrial Pollution."

Vernonia galamensis [(Cass.) Less.] is a native of Ethiopia and Eritrea. Seed of vernonia contain substantial quantities of naturally epoxidized oil, which is used in the paint industry to reduce emissions of volatile organic compounds that produce smog resulting from the use of petroleum-based (alkyd-resin) paint. Epoxidized oil is also used in the manufacture of plasticizers, additives to polyvinyl chloride, polymer blends and coatings, and cosmetic and pharmaceutical applications. Previous research has indicated that vernonia has potential for commercialization in the mid-Atlantic region of the United States. This study characterized fatty acids in oil from vernonia grown in this latter region. Vernonia oil, from 14 vernonia lines grown during 1995 and 1996 under field conditions in Virginia, contained 3.3, 3.0, 5.0, 15.0, 0.2, 0.5, 0.4, and 72.7%, respectively, of C16:0, C18:0, C18:1, C18:2, C18:3, C20:0, C20:1, and vernolic (C18:1 epoxy) fatty acids. Effects of genotypes on vernonia oil quality were generally not significant whereas the effects of years were significant. The concentration of vernolic acid was positively correlated with oil concentration but negatively correlated with concentrations of all individual fatty acids, except for C18:3. [ABSTRACT FROM AUTHOR]

Abundance, diversity, and richness of herpetofaunal species were compared between burned and unburned bottomland hardwood stands at Di-Lane Plantation Wildlife Management Area (WMA) in Burke County, Georgia, from July to October 2001. Two trap clusters, each consisting of a drift fence pitfall array, four coverboards, and three polyvinyl chloride (PVC) pipe refugia, were randomly placed within each of three burned and three unburned stands. Habitat variables were measured within a 0.04-ha circular plot centered on each trap cluster. A total of 346 individuals, representing 21 species, was captured in 348 array nights. Amphibian abundance, diversity, and richness were similar between burned and unburned stands. Reptile abundance and diversity were greater in burned stands, whereas reptile species richness was similar between burned and unburned stands. Winter burns did not significantly affect coarse woody debris volumes between burned and unburned stands and may have accounted for similar amphibian abundance, diversity, and richness. Greater reptile abundance and diversity in burned stands likely was a result of decreased ground cover providing greater thermoregulatory opportunities. [ABSTRACT FROM AUTHOR]

Investigates the structural changes of polyvinyl chloride (PVC) in melting blends of a low-density polyethylene (LDPE) and polyvinyl chloride and the effects of LDPE content and number of extrusion passes in the U.S. Use in the construction, automotive and consumer products; Method used to obtained the weight average molecular weight and number average weight of PVC; Effects in terms of changes in weight average molecular weight and number average molecular weight, polyene and carbonyl indices, color changes of the blend and the variations in glass transition and decomposition temperature.

While antifungal protection to preserve flexible PVC is the most widely found application for antimicrobial plastics additives in the U.S., other applications and use in other polymers is increasing. Jennifer Markarian looks at some recent developments in the field of antimicrobial additives for plastics and some of the trends in this area in North America. [Copyright &y& Elsevier]

The section of "The Production of Man-Made Fibres" focuses on chlorofibres. Chlorinated PVC fibres, now called Piviacid, and vinyl-chloride-vinyl-acetate copolymer fibres, now called Avisco, were among the first synthetic-polymer fibres to be marketed, in the 1930s in the U.S. and Germany. Poly vinyl chloride was the first synthetic polymer to be made into a fibre in 1913. Its thermal stability and the lack of solvents prevented its commercial production. A dry-spinning process was introduced in France in 1949, that used as solvent, a mixture of acetone and carbon disulphide at a temperature above the normal boiling points of the two components.

Vinyl chloride monomer (VCM) is classified as group 1 carcinogenic to humans by the International Agency for Research for Cancer (IARC). In 2012, USEPA promulgated a new VCM emission standard as part of National Emission Standards for Hazardous Air Pollutants (NESHAP) for polyvinyl chloride (PVC) and copolymer plants. The standard was set by benchmarking of peer plants with maximum achievable control technology (MACT). This study performs an emission assessment of a world-class PVC plant in Taiwan according to the MACT analysis. The emission data obtained were then benchmarked with baseline emission estimates of 15 PVC plants in the USA. Results of this study show seven types of VCM emissions: stripped resin of suspension/dispersion, wastewater, process vent, heat-exchange system, storage tank, equipment leaks, and other sources (gasholder). All the emission factors are complied with their MACT emission limitations (MEL) and ranked either #1 or #2 among the 15 plants. They are also summed and benchmarked against the production capacity of each plant, showing a negative power function with a fair correlation (R 2  = 0.73). Among seven types of emissions, stripped resin contributes the highest (51.7%) by average emission factor of the 15 plants plus this study plant.

The study determined concentrations of and estimated human exposure to house dust-ingested phthalates from 99 homes in Bangkok, Thailand. Phthalates in dust collected using a handheld vacuum cleaner was analyzed by gas chromatography/mass spectrometry revealing a median content of 3,477 µg g -1 , range 753-13,810 µg g -1 , with di-2-ethylhexylphthalate (DEHP) having the highest level (median = 1,739 µg g -1 , range 467-8,172 µg g -1 ) followed by di-iso-nonyl phthalate (DiNP) (median = 611 µg g -1 , range 15.2-11,052 µg g -1 ). DEHP in house dust from multi-family apartments with polyvinyl (PVC) floor material ( n  = 34), multi-family apartments without PVC floor material ( n  = 55) and single family houses without PVC floor material ( n  = 10) was median and range 3,009 and 568-6,898; 1,479 and range 467-8,172 and 1,207 µg g -1 and 611-3518 µg g -1 , respectively. At high-end house dust DEHP level, preschool children in all three types of homes were exposed above US Environment Protection Agency reference dose (20 µg g -1 ). The results suggest phthalate-containing house products constitute a likely major source of phthalates in indoor home environment and pose a potential health risk to residents, particularly preschool children, in Bangkok.