Dose reader

Dose reader for irradiated films. (Courtesy of Elektron CrossKnking AB.)... 

A dose reader designed for direct reading from exposed films, offered by Elektron Crosslinking AB of Sweden, is in Figure 9.2. 

A dose reader designed for direct reading from irradiated films... 

The measure used to describe the potential for noncarcinogenic toxicity to occur in an individual is not expressed as tlie probability of an individual suffering an adverse effect. The EPA does not at tlie present time use a probabilistic approach to estimate tlie potential for noncarcinogenic healtli effects. Instead, tlie potential for non carcinogenic effects is evaluated by comparing an exposure level over a specified time period (e.g., lifetime) witli a reference dose derived for a similar exposure period. Tliis ratio of exposure to toxicity is called a liazard quotient and is described below. (The reader is referred to Chapter 11 for additional details on tlie material tliat follows). The noncancer liazard quotient assumes tliat tliere is a level of exposure (i.e., RfD) below which it is unlikely for even sensitive populations to experience adverse healtli effects. 

If there are specific data germane to the assumption of dose-additivity (e g., if two compounds arc present at the same site and it is known that the combination is five times more toxic than the sum of the toxicitics for the two compounds), then tire development of the hazard index should be modified accordingly. The reader can refer to the EPA (1986b) mi.xiure guidelines for discussion of a hazjird index equation that incorporates quantitative interaction data. If data on chemical interactions are available, but arc not adequate to support a quantitative assessment, note the information in the assumptions being documented for the risk assessment. 

The reader should note tliat since many risk assessments have been conducted on the basis of fatal effects, there are also uncertainties on precisely what constitutes a fatal dose of thennal radiation, blast effect, or a toxic chemical. Where it is desired to estimate injuries as well as fatalities, tlie consequence calculation can be repeated using lower intensities of exposure leading to injury rather titan dcatli. In addition, if the adverse healtli effect (e.g. associated with a chemical release) is delayed, the cause may not be obvious. Tliis applies to both chronic and acute emissions and exposures. 

The primary objective of CICADs is characterization of hazard and dose-response from exposure to a chemical. CICADs are not a summary of all available data on a particular chemical rather, they include only that information considered critical for characterization of the risk posed by the chemical. The critical studies are, however, presented in sufficient detail to support the conclusions drawn. For additional information, the reader should consult the identified source documents upon which the CICAD has been based. 

LOAEL A Lowest-Observed-Adverse-Effeet Level (LOAEL) is the lowest dose used in the study that caused a harmful health effect. LOAELs have been classified into "Less Serious" and "Serious" effects. These distinctions help readers identify the levels of exposure at which adverse health effects first appear and the gradation of effects with increasing dose. A brief description of the specific end point used to quantify the adverse effect accompanies the LOAEL. The respiratory effect reported in key number 18 (h q)erplasia) is a Less serious LOAEL of 10 ppm. MRLs are not derived from Serious LOAELs. 

The preferred route of administration is intraperitoneal (IP) rather than IV to achieve maximum concentrations at the site of infection. Antibiotics can be administered IP intermittently as a single large dose in one exchange per day or continuously as multiple smaller doses with each exchange. Intermittent administration requires at least 6 hours of dwell time in the peritoneal cavity to allow for adequate systemic absorption and provides adequate levels to cover the 24-hour period. However, continuous administration is better suited for PD modalities that require more frequent exchanges (less than 6-hour dwell time). The reader should refer to the ISPD guidelines for dosing recommendations for IP antibiotics in CAPD and automated PD patients.49 The dose of the antibiotics should be increased by 25% for patients with residual renal function who are able to produce more than 100 mL urine output per day. 

The interested reader is referred to several other publications for more detailed information regarding these drugs.2,11,28,34-37,39-42 A summary of daily doses, adverse effects, and monitoring... 

Microsystems are also expected to be introduced in the near future, including for example artificial noses, fingerprint sensing systems, bar code readers, rf-tag-ging systems, microfluidic pumps and dosing systems, gas flow control systems, new flexible and low cost displays or electronic paper. 

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