United States national priority list

Endosulfan has been identified in at least 164 of the 1,577 hazardous waste sites that have been proposed for inclusion on the EPA National Priorities List (NPL) (HazDat 2000). However, the number of sites evaluated for endosulfan is not known. The frequency of these sites can be seen in Figure 5-1. Of these sites, 87 are located in the United States, one is located in Guam, and one is located in the Virgin Islands (not shown). 

Ethylbenzene was listed as one of the 58 most frequently detected chemicals associated with groundwater contamination in the United States. It was detected in over 4% of the surface water samples and 11% of the groundwater samples analysed at the 1177 National Priority List (NPL) sites (Agency for Toxic Substances and Disease Registry, 1997a). 

Exposure to isophorone may take place where you work or in very low concentrations at home. Because it is used in some inks, paints, lacquers, and adhesives, people who work with these products may be exposed to isophorone. Isophorone has been found in the drinking water of Cincinnati, Philadelphia, and New Orleans at amounts less than 10 parts of isophorone in 1 billion parts of water (10 ppb). In one instance (a screen print shop), isophorone was found in amounts as high as 26 parts in 1 million parts of air (26 ppm), but the usual amounts in the workplace are much lower. At this time, isophorone has been found in at least 9 out of 1177 National Priorities List (NPL) hazardous waste sites in the United States. Exposure to isophorone at these sites may occur by touching contaminated soil, water, or sediment. For more information please read Chapter 5. 

First of all, the CERCLA requires all hazardous waste releases over a prescribed threshold, known as reportable quantities (RQs), to be reported to National Response Center. Action is taken from that point to determine if it will be a CERCLA site. The CERCLA also established development of a National Contingency Plan. This plan includes all procedures for handling hazardous waste in the United States. The act also requires the creation of an uncontrolled hazardous waste site ranking system (HRS). The HRS determines if a site should be placed on the National Priorities List (NPL), which is a list of all the Superfund sites. 

According to the VIEW Database (1989), silver has been found at 27 sites on the National Priority List of 1,177 sites. The frequency of these sites within the United States can be seen in Figure 5-1. EPA s Contract Laboratory Program (CLP) statistical database indicates that silver has been detected at 100% of the 2,783 Superfund hazardous waste sites that have had samples of all media analyzed by the CLP (CLP 1988). 

National priorities list (NPL) A list of US sites contaminated with hazardous wastes that is maintained by the United States Environmental Protection Agency (US EPA). The sites are eligible for long-term remediation under the US EPA Superfund program. 

Perc spills have led to groundwater and soil contamination. Of 1190 National Priorities List sites in the United States, nearly two-thirds (771) have perchloroethylene contamination (ATSDR, 1995). Even filters and lint from perc machines must be disposed of as hazardous waste. In addition, ever-increasing taxes and regulations on the use of perchlor-othethylene reflect the growing public concern over continued use of this solvent. 

The Contract Laboratory Statistical Database reports that acrolein was detected in soil at 1 of 357 hazardous waste sites in the United States, at a mean concentration of 6.5 ppb (VIAR 1987). The National Priority List Technical Data Base (View 1989) indicates that acrolein was detected at 5 of 1177 National Priority List (NPL) sites however, the database does not contain media concentration data. Acrolein was identified in sediment/soil/water samples collected from Love Canal in Niagara Falls, NY (Hauser and Bromberg 1982) however, no quantitative data were available. 

NPL National Priorities List—the U.S. EPA s list of the most serious uncontrolled or abandoned hazardous waste sites in the United States, updated on a regular basis... 

There are presently over 26,000 uncontrolled waste sites in the United States as reported by the Environmental Protection Agency (EPA) (i). Of these sites, 951 are on the National Priority List (NPL) which makes these sites eligible for funds from the Superfimd. One common characteristic of the NPL sites is that the site ground water is contaminated by the leaching of pollutants from contaminated soil. Therefore, the task of cleaning up such a site involves the detoxification of both solid (soil) and liquid (water) matrices contaminated with a common pollutant. 

Many workers are exposed to copper in agriculture, industries connected with copper production, metal plating, and other industries. Little information is available concerning the forms of copper to which workers are exposed. Copper has been identified at many National Priorities List hazardous waste sites in the United States. 

Exposure to mirex occurs primarily from direct contact with contaminated soil or from consumption of contaminated food (e.g., fish). Mirex has been found in at least seven sites on US Environmental Protection Agency s National Priorities List of contaminated waste sites. Thus, since the use of mirex was eliminated in the United States in 1978, exposure would be most likely around contaminated waste sites. Mirex may still be used in other countries. 

Polychlorinated biphenyls (PCBs) were used in electrical capacitors, electrical transformers, vacuum pumps, and gas transmission tribunes. They were also used as hydraulic fluids, plasticizers, adhesives, fire retardants, wax extenders, lubricants and cutting oils, inks, dedusting agents, etc. PCBs are no longer commercially produced in the United States but are still found in the environment. PCB s have been found in at least 500 of the 1598 National Priorities List Sites identified by the Environmental Protection Agency (EPA). 

A likely set of compounds to consider for similar assay development are the nitroaromatic compounds shown in Figure 1 which are related to nitrobenzene (1). As a class, nitroaromatic compounds are of environmental concern since, as Figure 1 shows, they have been documented at as many as 30 of the 818 final EPA National Priority List (NPL) of waste sites in the United States ( ). The nitroaromatics most frequently found as environmental contaminants are 2,4-dinitrotoluene (2) and 2,6-dinitrotoluene (3) used in plastics, dyes and munitions production nitrophenols (4,5) used in pesticides and munitions wastes such at... 

---