Biocides and fungicides

Additives included in this category are antioxidants and antiozonants, antistats, biocides, and fungicides, heat stabilizers, light and UV stabilisers and absorbers . 

Table 3.23 contains general information on biocides and fungicides used in PVC. 

Toxicity concerns surrounding creosote have promoted the newer solventborne and waterborne systems. The use of more controlled, enclosed processes plus emission abatement recovery techniques will restrict emissions from the new solventborne types. There has been little debate, so far, about the relative environmental impacts of the different active biocides and fungicides used in the newer solvent- and water-based systems. 

Glucose Syrup and Com Syrup. Undiluted glucose syrup is an extremely viscous transparent Newtonian material with a viscosity of about 150 Pa s at room temperature. Com syrap has similar properties and has a viscosity of about 18 Pa s in undiluted form. At high viscosities both are extremely stable and will keep for a long period of time (months even). Once diluted with water (to about 1000 cP) biocide and fungicide should be added if solutions are to be kept for more than a day, as fermentation will take place, rendering the fluid unusable and producing an extremely unpleasant odor. 

Prior to the 1990s phenyhnercuric acetate was the primary bactericide and fungicide in latex and waterborne paints. Because of the increasing concerns of mercury toxicity and the potential for high consumer and occupational exposures to mercury when present in paints, the U.S. Environmental Protection Agency (EPA) induced U.S. manufacturers of PMA and other mercury compounds to withdraw their registrations for use of these substances as biocides in paints (see AIercury). Mercury compounds are used only for very limited, specific purposes, such as the use of phenyhnercuric mXx.2LX.e[55-68-5] as a bactericide in cosmetic eye preparations (see Cosmetics). 

It should be emphasized that ionic liquids are simply organic salts that happen to have the characteristic of a low melting point. Many ionic liquids have been widely investigated with regard to applications other than as liquid materials as electrolytes, phase-transfer reagents [12], surfactants [13], and fungicides and biocides [14, 15], for example. 

It does have a number of draw backs. It has poor thermal stability (a property common to most formaldehyde release biocides) and, in some instances, may cause blackening of metalworking fluid concentrates if heated above 50°C for a period of time. Recently, this active ingredient was placed on Annex 1 of the Dangerous Substances Directive having been identified as a potential skin sensitiser. This means that formulations containing efficacious levels of this class of triazine in them would have to be labelled with R43 - may cause sensitisation by skin contact. This is unacceptable to many UK customers. As this material is only bactericidal, it needs to be co-formulated with a fungicide to provide complete protection for a product. 

Among the abiotic factors most widely used to manipulate and vary the metabolism of phenolics, are biocides, primarily herbicides and fungicides, and different nutrients. 

Insecticides and fungicides used in interiors are the same as those used in agriculture and forestry, but herbicides are seldom applied indoors (Butte, Schencke and Heinzow, 2006). In contrast to the outdoor environment, where modern pesticides are degraded rather quickly by microorganisms, hydrolysis and UV light, biocides applied indoors tend to be persistent. Adsorbed to a dry and dark medium such as house dust, an abiotic degradation may hardly occur and... 

Flick, E.W. (1987) Fungicides, Biocides and Preservatives for Industrial and Agricultural Applications. 

Key terms such as disinfection, sterilization and preservation are defined in Chapter 17 but other terms are often employed to describe the antimicrobial activity of agents. Hence, terms such as biocidal, bactericidal, virucidal and fungicidal describe a killing activity, whereas bacteriostatic and fungistatic refer to inhibition of growth of the organism... 

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