Potential exposure

In comparison with most other analytical techniques, radiochemical methods are usually more expensive and require more time to complete an analysis. Radiochemical methods also are subject to significant safety concerns due to the analyst s potential exposure to high-energy radiation and the need to safely dispose of radioactive waste. 

The nature of potential exposure ha2ards of low level microwave energy continues to be investigated (116—118). In the United States, leakage emission from microwave ovens is regulated to the stringent limit of 5 mW/cm at 5 cm (119). There is no federal limit on emission from industrial systems but the IMPI has set a voluntary standard which specifies 10 mW/cm at 5 cm (120). Emission values are equivalent to personnel exposures at several meters, well below limits that had previously prevailed in eastern Europe. This conclusion, derived for microwave ovens, should be vaUd for all microwave systems (121). 

Two large studies were done (250,251) for the selection of a2o, nitro, and anthraquinone dyes for carcinogen bioassay. Based on previous information or testing, a total of 30 dyes were selected based on chemical stmcture, potential exposure, and suspicion of carcinogenicity. 

Toxicity. Low toxicity from solvent-vapor inhalation or skin contac t is preferred because of potential exposure during repair of equipment or while connections are being broken after a solvent transfer. Also, low toxicity to fish and bioorganisms is preferred when extraction is used as a pretreatment for wastewater before it enters a biotreatment plant and with final effluent discharge to a stream or lake. Often solvent toxicity is low if water solubility is high. 

Exposure assessment techniques now attempt to include as many as possible of the locations in which individuals now spend time. The concept involves identification of microenvironments which are important for potential exposure. For example, exposure to CO would include time spent in commuting, parking garages, in residences with gas stoves, as well as time spent outdoors. This approach classifies time spent in these microenvironments and the typical concentrations of CO in these locations. 

For most ehemieals, inhalation is the main route of entry into the body. Penetration via damaged skin (e.g. euts, abrasions) should, however, be avoided. Certain ehemieals (e.g. phenol, aniline, eertain pestieides) ean penetrate intaet skin and so beeome absorbed into the body. This may oeeur through loeal eontamination, e.g. from a liquid splash, or through exposure to high vapour eoneentrations. Speeial preeautions to avoid skin eontaet are required with these ehemieals and potential exposure via skin absorption has to be taken into aeeount when assessing the adequaey of eontrol measures. 

Each alternative should be assessed in terms of the extent to which it mitigates short- and long-term potential exposure to any residual contamination and protects human health, both during and after implementation of the corrective measure. 

Fire as a Cause of Overpressure - Equipment in a plant area handling flammable fluids is subject to potential exposure to external fire, which may lead to overpressure resulting from vaporization of contained liquids. This hazard may exist even in items of equipment containing nonflammable materials. 

Review potential exposures and the HASP to determine if additional testing is required. 

Operations resulting in potential exposure to a regulated chemical or radiological agent, as prescribed by DOE and OSHA action levels, or to a bloodborne pathogen... 

Prior to beginning any training activity, exact training needs should be identified. Training needs may vary based on hazards, potential exposures, work requirements, roles and responsibilities, job descriptions, and compliance requirements. Job hazard analyses and employee surveys... 

Lewis RG, Fortmann RC, Camann DE. 1994. Evaluation of methods for monitoring the potential exposure of small children to pesticides in the residential environment. Arch Environ Contam Toxicol 26 37-46. 

Endosulfan is a popular pesticide with greenhouse chrysanthemum producers. Surveys of usage patterns and potential exposure were conducted in Ontario (Archibald et al. 1994b). Collection and analysis of a-and P-endosulfan and endosulfan sulfate in greenhouse air have been described (Vidal et al. 1997). Results indicate that 7.5% of the initial concentration of endosulfan remained in the greenhouse atmosphere 24 hours after application. 

Before the EPA proceeds on a regulatory action, registrants whose products exceed the 10 risk level from nitroso contamination, will be given the opport mity to lower potential exposure to applicators and other users of their pesticides. Reduction of exposure and, thus, reduction of risk can be accomplished by modification of the manufacturing process (see below), improved packaging technology, modification of application technique (e.g. closed systems), or deletion of high-exposure uses. 

Tables XXI and XXII show that for the RSR site the differences In mean blood-lead levels and proportion of children with lead toxicity remain evident even when other sources of potential exposure (as determined from the questionnaire) were taken Into consideration Tables XXIII and XXIV show this Is not the case for the Dixie site ...

Approximate Distance (miles) Traffic Density Sample Size Potential Exposure YES NO Percent with Lead Toxicity Other Potential Exposure YES NO ... 

Distance Traffic Potential Exposure Other Potential Exposure ... 

Fourteen formulations of chemical alternatives were submitted to EPA under confidentiality and they were assessed based on numerous human health and ecotoxicity endpoints in addition to bioaccumulation potential and environmental persistence. They were also screened for potential exposure to workers, users and the aquatic environment. Where data gaps existed, EPA experts used models and chemical analogs to estimate the hazard for a particular endpoint. The literature and test data reviews were published in the final report, Environmentally Preferable Options for Furniture Fire Safety Low Density Furniture Foam . In addition, each hazard endpoint was ranked with a concern level (High, Moderate or Low) based on the criteria used by the EPA s New Chemicals Program to rate the concern level of new chemicals submitted under the Toxic Substance Control Act (TSCA). As seen in Figure 8.2, where the hazard endpoint rankings are bold, the value is based on experimental data. Where the hazard endpoints are presented in italic font, the value is estimated based on models or chemical analogs. In this way, detailed hazard information was summarized and presented in a clear and concise format. 

In the USA, the passage of the Food Quality Protection Act (FQPA) of 1996 has had a significant impact on the determination of residues in drinking water. FQPA requires that all sources of a pesticide be included in its risk assessment, so the potential exposure from drinking water containing a particular pesticide could be a significant... 

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