[TABULAR DATA FOR TABLE 1 OMITTED] TABLE 2 Environmental Transport Pathway Evaluation Transport Pathway Rumpke Landfill Air Odors present; low levels of methane and other volatile organic compounds found on site Disease Vectors Insects and birds Surface Water No contaminants found Groundwater Unable to sample - low volume of groundwater available Soil Not applicable TABLE 3
Exposure Pathway Analysis
Exposure Pathway Rumpke Landfill Source Landfill solid wastes Transport Pathways Air and disease vectors Exposure Area On site to within one-mile radius of the site Exposure Route Inhalation Impacted Population Workers and residents within a one-mile radius
Persons exposed through multiple
exposure pathways were also at increased risk.
Other sources, such as food packaging, may be important DEHP
exposure pathways (Koch et al.
(2005) analyzed both marine and freshwater
exposure pathways, assuming a linear and instantaneous change in fish Hg levels with declines in atmospheric deposition.
[34] Our figure, although lower because our subjects did not comprise only pregnant women, shows that geophagia is not a negligible factor in the assessment of uranium
exposure pathways. The study participants consumed soil from their own yards (or neighbours' or relatives' yards) and from roadside vendors.
Significant among these improvements are a) addressing spatiotemporal and population-level resolution challenges to estimate impact potential; b) addressing chemical substances in consumer products and in occupational settings, and adding related human
exposure pathways that are currently missing; c) extending the limited coverage in available dose-response data and models; and d) improving the coverage and quality in databases on substance physicochemical properties and toxicity information.
If the examined characteristics of outbreak and sporadic cases are different for these data, then the assumption of similar
exposure pathways is less plausible.
The OEHSA uses a conceptual site model to describe potential
exposure pathways which serve as the basis for developing the site surveillance and analysis plan.
Several types of SHEDS-IEUBK runs were conducted: a) for model evaluation, a national-scale analysis using NHANES data, and a regional-scale analysis using NHEXAS Region 5 data; b) for analyzing relative contributions by
exposure pathway in the United States and NHEXAS Region 5; c) for sensitivity analyses to identify key factors; and d) for national-scale runs with a set of alternative drinking water Pb concentration scenarios to develop the linear relationships between concentration and BLL percentiles, shown in the bottom left of Figure 1.
The number of samples collected during an exposure investigation varied depending on site-specific factors such as the
exposure pathway, sample media, and the number of persons potentially exposed.
None of the environmental exposure studies prospectively assessed neonicotinoid-treated produce as the primary
exposure pathway. Instead, two considered exposures through air and water based on proximity to agricultural fields, and one examined exposures through the use of flea and tick medications on pets.
Their results clearly establish an
exposure pathway between anthropogenic activity and drinking water supplies, suggesting that the causative agent for BEN could result from surface contamination.