Potential Population Exposure

The committee also examines how emergency response professionals estimate the potential population exposure from a chemical event, reviews emergency response activities and public responses, and discusses how the events are communicated to local news media and interested citizens groups. These communications have important implications, since they affect how political leaders, regulators, and the general public view the chemical demilitarization program. 

POPULATIONS WITH POTENTIALLY HIGH EXPOSURES ADEQUACY OF THE DATABASE... 

The greatest potential for exposure of the general population to methyl parathion is by consumption of food containing residues from spray applieations of the inseetieide. In a 10-year study, methyl parathion was found at an average concentration of 0.0035 ppm in a few examples of ready-to-eat foods. Concentrations in the range of 0.05-2.0 ppm were reported in 0.5% of the samples of domestie and... 

A susceptible population will exhibit a different or enhanced response to methyl parathion than will most persons exposed to the same level of methyl parathion in the environment. Reasons may include genetic makeup, age, health and nutritional status, and exposure to other toxic substances (e g., cigarette smoke). These parameters result in reduced detoxification or excretion of methyl parathion, or compromised fimction of organs affected by methyl parathion. Populations who are at greater risk due to their imusually high exposure to methyl parathion are discussed in Section 6.7 Populations With Potentially High Exposures. 

In addition to individuals who are occupationally exposed to endosulfan (see Section 5.5), there are several groups within the general population that have potentially high exposures (higher than background levels) to endosulfan. These populations include individuals living in proximity to sites where endosulfan was produced or sites where endosulfan was disposed of, and individuals living near one of the 162 NPL hazardous waste sites where endosulfan has been detected in some environmental media (HazDat 2000). 

Populations with potentially high exposure to 241Am from commercial devices such as ionization chamber smoke detectors might include production workers and firemen attending to fires in production facilities, warehouses where a large number of sources or devices are housed, or homes where a small number of the devices might be used. 

Exposure Levels in Environmental Media. Monitoring data were not located for diisopropyl methylphosphonate in ambient air. This chemical has been detected in surface and groundwater receiving effluent from the RMA (ATSDR 1996). It has also been detected in soil at the RMA. Since this chemical is not expected to be prevalent in the environment and exposure of the general population is not expected to be of concern, monitoring of ambient environmental media does not appear to be required. However, monitoring of environmental media such as groundwater and soil in the vicinity of the RMA has been conducted to help determine the potential for exposure. 

Populations who are at greater risk due to their unusually high exposure are discussed in Section 5.6, Populations With Potentially High Exposure. 

Mineral Oil Hydraulic Fluids. Populations with potentially high exposures to mineral oil hydraulic fluids include all occupations that maintain hydraulic equipment including automobile, truck, and tractor mechanics, mechanics employed by heavy industry and mining operations to repair and maintain hydraulic equipment, and other maintenance workers involved with the repair and maintenance of hydraulic systems. The number of workers with potentially high exposures to mineral oil hydraulic fluids is expected to be very large. 

Organophosphate Ester Hydraulic Fluids. Populations with potentially high exposures to organophosphate ester hydraulic fluids include aircraft mechanics and other mechanics repairing and maintaining hydraulic equipment designed to operate near combustion sources that require fire resistant hydraulic fluids. 

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