Volatiles emissions

There has been increasing concern among sections of the public about indoor air quality and the so-called sick building syndrome . Some public authorities are concerned about the role played by synthetic materials such as vinyl flooring, curtains, wood, paint and laminates in the formation of traces of volatile contaminants. 

Several formulation ingredients contribute to volatile emissions, including plasticisers, viscosity modifiers and liquid metal soaps. An investigation of some flexible PVC formulations by Dover Chemical Corp. foimd that the majority of the emissions were aliphatic hydrocarbons derived from the compatibihsing agents in the barimn/zinc stabilisers. An organophosphate-based stabiliser was recommended, in combination with zinc carboxylate. The elimination of the barimn soap did not spoil the thermal stability. 

Phenols can sometimes be generated by a reaction between hydroxyl-containing solvents (alcohols and diols) and phosphite co-stabilisers. Concerns have been expressed about the toxicology of nonyl phenol from tris(nonylphenyl)phosphite, a liquid phosphite stabihser. 

A recent Dover Chemical patent discloses a stabiliser system based on a combination of liquid organic phosphites, pentaerythritol, alkyl alcohols and alkyl phenols. The products are said to be virtually phenol-free and, imlike some additives, are compatible with mixed metal stabilisers. 

A different aspect of the volatile emissions and odom problem arose recently in North America when processors asked Akcros America to develop barium-zinc stabilisers for use in PVC garment bags and reusable packaging made from calendered or extruded film. These are products where odour obviously has to be minimised. The outcome was the stabiliser Interstab 5216, now used to provide good film clarity and processing characteristics in extruded and blown packaging film, of the type used to wrap flowers. 

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For VOCs, control options are multiple. Source reduction or removal includes product substitution or reformulation. Particleboard or pressed w ood has been developed and used extensively in building materials for cabinet bases and subflooring and in furniture manufacturing for frames. If the product is not properly manufactured and cured prior to use as a building material, VOCs can outgas into the interior of the residence or building. Other sources of VOCs may be paints, cleaning solutions, fabrics, binders, and adhesives. Proper use of household products will lower volatile emissions. 

Floating polyethylene spheres are capable of reducing volatile emissions by up to 90%. Polyethylene spheres are compatible with a broad range of compounds including inorganic acids and bases and most aromatic and aliphatic organic compounds.16... 

Egg-deposition also can induce the host plant to emit volatiles that attract egg parasitoids. For example, egg deposition by the elm leaf beetle (Xantho-galeruca luteola) causes its host plant, the field elm (Ulmus minor), to release a blend of mostly terpenoids that attract the egg parasitoid Oomyzus galleru-cae (Eulophidae) [ 86]. Although the specific compounds that initiate the volatile emission and that attract the egg parasitoid are unknown, the host plant response can be induced with jasmonic acid. 

For vessels being filled with liquid, volatile emissions are generated from two sources, as shown in Figure 3-4. These sources are... 

An expression that can be used to estimate the volatile emission rate in a storage tank resulting from a single change in temperature is given by... 

Methods for achieving low styrene emissions in the unsaturated polyester resin industry are discussed. The necessity for new formulations to maintain the same mechanical properties as the previous ones is considered. The environmental requirements and working conditions that make essential the development of new formulations and processes that reduce volatile emissions are examined. The need for factories to adopt alternative technologies in order to comply with the latest environmental restrictions is discussed. 12 refs. 

Other aspects of implementing indirect volatile defenses, as recently discussed in several excellent reviews [17, 94, 95], will include the assessment of timing and synergy of volatile emissions with direct defense responses of the herbivore-damaged plant, especially if indirect defense strategies will be integrated with toxin-based pest control strategies. 

Kessler A, Baldwin IT (2001) Defensive function of herbivore-induced plant volatile emissions in nature. Science 291 2141-2144... 

Mithofer A, Wanner G, Boland W (2005) Effects of feeding Spodoptera Uttoralis on lima bean leaves. II. Continuous mechanical wounding resembling insect feeding is sufficient to elicit herbivory-related volatile emission. Plant Physiol 137 1160-1168... 

All three cresol isomers were identified as volatile emissions of fried bacon (Ho et al. 1983). Various brands of Scotch whiskey, whiskeys made outside of Scotland, cognac, armagnac, brandy other... 

Dusts and volatile emissions may be generated during the MVS technology, requiring dust control methods to minimize particulate emissions. Also, the handling and processing of soils may require the use of amendments to reduce the moisture content of the soils to be processed. 

According to the vendor, the technology is most effective on soils contaminated with TPH or low-molecular-weight PAHs. Based on specific site characteristics, volatile emissions may need to be controlled during excavation and treatment. 

Solvents, defined as substances able to dissolve or solvate other snbstances, are commonly used in manufacturing and laboratory processes and are often indispensable for many applications such as cleaning, fire fighting, pesticide delivery, coatings, synthetic chemistry, and separations (Grayson, 1985). Billions of ponnds of solvent waste are emitted to the environment annnaUy, either as volatile emissions or with aqneons... 

The second impregnation option also employs an open resin-filled bath, but the reinforcement is not guided down into the bath rather, it horizontally enters and exits the bath through holes and/or slots in the resin container and thus maintains its horizontal travel. The major advantage of this method, which often is used in production of hollow composites, is that the reinforcement does not need to be bent, which otherwise may exclude the use, or at least wrinkle or rip, of vertically oriented fabrics, mats, and veils. This impregnation method also has the disadvantage of significant volatile emissions. 

Vapor pressure has also become a means of regulating storage tank design by the EPA. Because increasing vapor pressure tends to result in an increase in volatile emissions, the EPA has specific maximum values of vapor pressure for which various tank designs may be used. 

Plant hormones with various functions have been identified over the years and an increasing number of studies show that they may also affect volatile emissions... 

The ethylene-insensitive plants also showed reduced defense protein synthesis and were susceptible to soil pathogens to which they were normally fully resistant. In connection with the third trophic level, Kahl et al. (2000) found that attack by Manduca caterpillars on wild tobacco plants causes an ethylene burst that suppressed induced nicotine production but stimulated volatile emissions. They argued that the plant chooses to employ an indirect defense (the attraction of natural enemies) rather than a direct defense to which the attacker could adapt (Kahl et al, 2000 Winz and Baldwin, 2001). This implies that the plant is capable of identifying its attacker. We discuss this possibility in more detail in the discussion of specificity. 

This rather unspecific induction of nectar secretion in cotton was surprising in light of the fact that the induction of volatile emission by this plant had been demonstrated to be specific. Herbivore-damaged plants show a higher rate of volatile emission compared with mechanically damaged plants (McCall et al, 1994), and herbivore feeding induced de novo synthesis of various terpenoids (Pare and Tumlinson, 1997), which resulted in a quantitative as well as a qualitative response to herbivory. The specificity of the plant response is not restricted to the differentiation between mechanical damage and herbivory. The composition of the induced volatile blend also varies between (even closely related) herbivore species (De Moraes etal, 1998). 

Bernasconi Ockroy, M. L., Turlings, T. J. C., Edwards, P. J. et al. (2001). Response of natural populations of predators and parasitoids to artificially induced volatile emissions in maize plants (Zea mays L.). Agricultural and Forest Entomology 3 ... 

Cardoza, Y. J., Alborn, H. T. and Tumlinson, J. H. (2002). In vivo volatile emissions from peanut plants induced by simultaneous fungal infection and insect damage. Journal of Chemical Ecology 28 161-174. 

Gouingucne, S. and Turlings, T. C. J. (2002). The effects of abiotic factors on induced volatile emissions in com plants. Plant Physiology 129 1296-1307. 

Rodriguez-Saona, C., Crafts-Brander, S. J., Pare, P. W. and Henneberry, T. J. (2001). Exogenous methyl jasmonate induces volatile emissions in cotton plants. Journal of Chemical Ecology 27 679-695. 

Gemeno, C., Yeargan, . V. and Haynes, K. F. (2000). Aggressive chemical mimicry by the bolas spider Mastophora hutchinsoni identification and quantification of a major prey s sex pheromone components in the spider s volatile emissions. Journal of Chemical Ecology 26 1235-1243. 

Loughrin, J. H Hamilton-Kemp, T.D, Andersen, R. A. and Hildebrand, D.F. (1991). Circadian rhythm of volatile emission from flowers of Nicotiana sylvestris and N. suaveolens. Physiologia Plantarum 83 492-496. 

Degen, T., Dillman, C., Marion-Poll, F., and Turlings, T.C.J. 2004. High genetic variability of herbivore-induced volatile emission within a broad range of maize inbred lines. Plant Physiology 135 1928-1938. 

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