Hazardous waste sites, importance

Only qualified individuals should be allowed to develop air monitoring strategies. In addition, only trained and qualified field personnel should operate sereening equipment and be allowed to interpret results. For many sites, the results obtained from direet reading instruments ean help determine a variety of important faetors on a hazardous waste site. These faetors inelude ... 

The inspeetion team should obtain a eopy of the site s most reeent SAHP Beeause eonditions on the hazardous waste site ehange so rapidly, it is important that the SAHP be eurrent OSHA s experienee shows that it is not uneommon for the site SAHP to be out of date. At a minimum, the SAHP should address the following elements ... 

The Environmental Protection Agency (EPA) identifies the most serious hazardous waste sites in the nation. These sites make up the National Priorities List (NPL) and are the sites targeted for long-term federal cleanup activities. Methyl parathion has been found in at least 16 of the 1,585 current or former NPL sites. However, the total number of NPL sites evaluated for this substance is not known. As more sites are evaluated, the sites at which methyl parathion is found may increase. This information is important because exposure to this substance may harm you and because these sites may be sources of exposure. 

Your children may be exposed to endosulfan if unquahfied people apply pesticides around your home. In some cases, the use of pesticides that have been banned for use in homes has turned homes into hazardous waste sites. Your state licenses each person qualified to apply pesticides using EPA standards and further certifies each person qualified to apply restricted use pesticides. Ask to see the license and certification of anyone who applies pesticides for you. Also ask for the brand name of the pesticide, a material safety data sheet (MSDS), the name of the product s active ingredient, and the EPA registration number. Ask whether EPA has designated the pesticide for restricted use and what the approved uses are. This information is important if you or your family have a reaction to the product. 

Production, Import/Export, Use, Release, and Disposal. Endosulfan is distributed in the environment as a result of its use as an insecticide (Gregor and Gummer 1989 NRCC 1975 Strachan et al. 1980). Humans may be exposed through the ingestion or use of contaminated food (Gartrell et al. 1986 Podrebarac 1984a) or tobacco products (EPA 1982a), contact with media from contaminated hazardous waste sites (principally soils), or insecticide apphcafion (Oudbier et al. 1974 Wolfe et al. 1972). 

These substance-specific estimates, which are intended to serve as screening levels, are used by ATSDR health assessors to identify contaminants and potential health effects that may be of concern at hazardous waste sites. It is important to note that MRLs are not intended to define clean-up or action levels. 

Environmental Fate. Hydrogen sulfide is known to easily evaporate into the air (EPA 1993 Layton and Cederwall 1986 Leahey and Schroeder 1986), although its solubility in water may also cause it to persist in unperturbed, anoxic sediments. Additional information on the transport, transformation, and persistence of the compound in soils and groundwater, particularly at hazardous waste sites, would be useful in identifying the most important routes of human exposure to hydrogen sulfide. 

People living near hazardous waste sites may be exposed to lead via ingestion of contaminated water or soils or by inhalation of lead particles in the air. For people not living in the vicinity of hazardous waste sites, the major route of exposure to lead is ingestion, particularly of lead-contaminated water, food, soil, lead-based paint chips, or dusts (the latter two are particularly relevant to children in lower-income urbanized populations). For occupationally exposed individuals, the predominant route of exposure is the inhalation of lead particles with oral ingestion also important in many cases. 

An MRL is an estimate of the daily human exposure to a hazardous substance that is likely to be without appreciable risk of adverse noncancer health effects over a specified duration of exposure. MRLs are based on noncancer health effects only and are not based on a consideration of cancer effects. These substance-specific estimates, which are intended to serve as screening levels, are used by ATSDR health assessors to identify contaminants and potential health effects that may be of concern at hazardous waste sites. It is important to note that MRLs are not intended to define clean-up or action levels. 

The main sources for potential human exposure to endrin are residues on imported food items, unused stocks, unregistered use, inappropriate disposal, and hazardous waste sites however, there is no current evidence of significant exposures from any of these sources. Furthermore, it should be noted that in environmental media, especially in contaminated soils and sediments, the amount of endrin chemically identified by analysis is not necessarily the amount that is toxicologically available. 

No acute-duration inhalation MRL could be derived for mirex because no inhalation data could be located. No acute-duration oral MRL was derived for mirex because serious effects (heart block and arrhythmias in fetuses from dams exposed during gestation) were observed at the lowest dose tested (Grabowski 1983a). Studies examining the effects of mirex and chlordecone after acute-duration dermal exposure would be helpful since persons at hazardous waste sites may be exposed dermally to mirex. Additional dermal studies are certainly necessary because skin absorption of chlordecone appears to be an important route of exposure (Taylor et al. 1978). However, populations at hazardous waste sites are unlikely to be exposed via inhalation since these substances are virtually nonvolatile, so future studies using this route of exposure are not essential. 

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