Scope In response to the current public health concerns with the microbiological safety of fresh and fresh-cut produce, researchers have investigated the efficiency of numerous physical, chemical, and biological methods for reducing the microbiological load of produce. This chapter focuses on this growing area of research with a particular emphasis on human pathogenic microorganisms; however, research related to mitigation treatment effects on nonpathogenic organisms is also included. There have been several reviews that address this topic and they are pointed out throughout the chapter; therefore, the focus here is on the latest and most significant research findings. A matrix (Table V-1) summarizing the characteristics of intervention methods is also included at the end of the chapter.

Methods to Reduce/Eliminate Pathogens from Fresh and Fresh-Cut Produce

Bacterial spores are among the most resistant of all living cells to biocides, although the response depends on the stage of sporulation. The development of resistance to some agents such as chlorhexidine occurs much earlier in sporulation than does resistance to glutaraldehyde, which is a very late event. During germination or outgrowth or both, resistance is lost and the cells become as susceptible to biocides as nonsporulating bacteria. Mechanisms of spore resistance to, and the action of, biocides are discussed, and possible means of enhancing antispore activity are considered. The clinical and other uses of sporicidal and sporostatic chemical agents are described.

Bacterial spores and chemical sporicidal agents.

This review includes a general discussion of N‐halamine compounds which function as biocides in water. Advantages and limitations of the compounds as compared to free chlorine and other disinfectants are presented. The discussion addresses N‐halamines which are, or have been, in commercial use, but special emphasis will be placed upon two new classes of N‐halamine compounds (oxazolidinones and imidazolidinones) which are under intensive study in the laboratories of the authors. These new N‐halamine compounds are considerably more stable in water than previous ones; the factors dictating their enhanced stabilities are discussed. Potential applications for the new compounds are also addressed.

Halamine water disinfectants

After the intentional release of Bacillus anthracis through the U.S. Postal Service in the fall of 2001, many environments were contaminated with B. anthracis spores, and frequent inquiries were made regarding the science of destroying these spores. We conducted a survey of the lit- erature that had potential application to the inactivation of B. anthracis spores. This article provides a tabular sum- mary of the results. consistent between experiments, but each experiment pro- vides some specific information of value. Early studies that lack quantitative data are not included. A number of the cited studies address Bacillus species other than B. anthracis. We include these for information, with the caveat that surrogates do not always predict the behavior of the target species. Furthermore, the results from labora- tory experiments do not specifically address questions regarding the best methods for inactivating spores on dif- ferent materials such as mail, carpet, other porous objects, food, or water. Transfer of these sporicidal methods from the laboratory to a building has not yet been tested; how- ever, the known laboratory results are a logical place to start when considering the decontamination of a building. Decontamination is defined as the irreversible inactiva- tion of infectious agents so that an area is rendered safe. However, decontamination may not eliminate bacterial spores. Sterilization is the complete destruction or elimina- tion of microbial viability, including spores (3). The experiments described provide a logical starting point for future experiments and decontamination strate- gies in the event of anthrax bioterrorism. Our intent is not to provide a comparative evaluation or recommendations for decontamination but rather to summarize the quantita- tive published results and provide a useful reference. Review

Inactivation of Bacillus anthracis spores.

Inactivation of Mycobacterium tuberculosis and Mycobacterium bovis by 14 hospital disinfectants

A Standard Test for Efficacy of Germicides and Acceptability of Residual Disinfecting Activity in Swimming Pool Water

The Behavior of Chlorine-Bearing Organic Compounds in the A.O.A.C. Available Chlorine Germicidal Equivalent Concentration Test

The Sporicidal Activity Of Ethylene Oxide As Measured By The A.O.A.C. Sporicide Test

Collaborative Study of Improved Sporicidal Test

http://academic.oup.com/jaoac/article-pdf/44/3/416/32604707/jaoac0416.pdf

L F Ortenzio

Papers

A Standard Test for Efficacy of Germicides and Acceptability of Residual Disinfecting Activity in Swimming Pool Water

The Behavior of Chlorine-Bearing Organic Compounds in the A.O.A.C. Available Chlorine Germicidal Equivalent Concentration Test

The Sporicidal Activity Of Ethylene Oxide As Measured By The A.O.A.C. Sporicide Test

Collaborative Study of Improved Sporicidal Test

Adaptation of the Use-Dilution Method to Primary Evaluations of Disinfectants