Hazards cell disruption

When carrying out cell disruption operations it is often necessary to provide cooling of the cell concentrate due to the high pressures developed in the equipment. An additional consequence of high-pressure operation is that cell disruption equipment can generate aerosols which may be undesirable, particularly for biologically hazardous organisms. In these cases, the ability to steam sterilize the equipment is required, for decontamination, and some type of secondary containment may also be required, such as an isolator or a contained area within a facility to which access is controlled. 

A tubular sonicatlon device was recently reported by Borthwick et al. [93] (see Fig. 3.9). The device requires the addition of no chemical, enzyme or particles that might complicate the subsequent determination step. Furthermore, denaturatlon of target DMA or proteins for detection Is minimized as the device tolerates moderate temperature rises this allows the use of sensitive and specific Immunological detection methods on sonicated biological materials. Because the tubular device Is composed of a piezoelectric resonator made of several material layers, selection of an appropriate operating frequency Is essential to ensure proper performance (i.e. acceptable cell disruption efficiency). This device can be used for batchwise treatment of small sample volumes or In flow systems without the risk of hazardous aerosol formation inherent in probe sonloators. 

If non-physical methods of cell disruption can be developed to the stage where they are cost-effective at large-scale, the requirement for physical methods will decrease. There is no doubt that high pressures and high speed rotating shafts increase the risk of a breach of containment and subsequent production of hazardous aerosols. It is predictable that the trend of research will be towards non-physical methods of cell disruption and their application at large-scale. 

Different organic acids, primarily lactic acid, have been successfully used for decontamination of whole livestock carcasses, and the application of different organic acids used for decontamination has also been tested in the fruit and vegetable industry. Organic acids other than lactic acid that are known to have bactericidal effects are acetic, benzoic, citric, malic, propanoic, sorbic, succinic and tartaric acids (Betts and Everis 2005). The antimicrobial action is due to a reduction in the pH in the bacterial environment, disruption of membrane transport, anion accumulation or a reduction in the internal pH in the cell (Busta et al., 2001). Many fruits contain naturally occurring organic acids. Nevertheless, some strains, for example E. coli 0157, are adapted to an acidic environment. Its survival, in combination with its low infective dose, makes it a health hazard for humans. 

OEHHA Office of Environmental Health Hazard Assessment OSHA Occnpational Safety and Health Administration Osteogenic sarcoma Cancer associated with bone structures Oxidation Chemical addition of oxygen to break down pollutants or organic waste, for example, destruction of chemical substances such as cyanides, phenols, and organic sulfur compounds in sewage by bacterial and chemical means Oxidative stress Process whereby the metabolic balance of a cell is disrupted by exposure to environmental substances, resulting in accumulation of free radicals, which can damage the cell... 

Many other cell lines have been used to address specific types of toxicity. Some of these have reached a level of validation that is sufficient for in vitro screening purposes. For example, the 3T3 NRU assay was regarded as an acceptable screen for hazard identification of potential phototoxicity [27,28], This assay utilized the in vitro 3T3 cell line as a generic cell line and Neutral Red uptake as a cytotoxicity measurement. The compound in question is subjected to UV irradiation to assess the effect of UV rays on compound induced toxicity to 3T3 cells. Another example is the use of the MCF-7 cell proliferation assay as an in vitro screen for endocrine disrupters [29],... 

Hazard characterization Data on toxicokinetics for the AZA group are lacking, mainly due to lack of availability of pure toxins. Also, information on the mechanism of action is scarce, but they do not inhibit protein phosphatise 2A, which is the main mechanism of DSP toxins [3]. Results from in vitro studies have shown multiple effects like cytoskeleton disruption [32], increased levels of cytosolic calcium and cAMP [33,34], and cytotoxicity towards multiple cell types [3]. 

A report released by the national environmental health group Women s Voices for the Earth (WVE) (htq> //www.womensvoices.org/wp-content/uploads/2010/05/ Disinfectant-OverkilLpdf) linked disinfectant chemicals with chronic illnesses and conditions such as asthma, hormone imbalance, and immune system problems in a report titled Disinfectant Overkill How Too Clean May Be Hazardous to Our Health, which cited more than 40 peer-reviewed reports and scientific studies. According to the report Triclosan and Triclocarban, two antibacterial disinfectants may have hormone-disrupting effects Triclosan adversely affects communication between cells in the brain and the heart while Triclocarban appears to amplify testosterone in the body (http //www.womensvoices.org/wp-content/uploads/2010/05/ Disinfectant-OverkilLpdf). The physical and chemical properties of disinfectants and their byproducts can influence their behavior in drinking water. 

Pedersen et al. (2006) describe the cascading effects of a freight train derailment in a tunnel, carrying hazardous chemicals. It caused a fire that led to a water main to break above the tunnel causing localized flooding. The fire also destroyed the fiber optic cables in the tuimel that resulted in major disruptions to phone and cell phone service, email service, and data services to major corporations. Disruption to rail services and the consequent delays in deliveries of coal and limestone were significant. 

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