TABLE 2.
Survey of recent risk assessment parameter selections utilized for risk assessment of incidental ingestion resulting from direct contact with sediment
| Reference | Type of guidance or assessment | Location and medium(-a) | Scenario | Sediment ingestion rate (mg/day) | Reference(s) for ingestion rate | Exposure
|
|
|---|---|---|---|---|---|---|---|
| Duration (yrs) | Frequency (days/yr) | ||||||
| Generic guidance | |||||||
| 74 | Risk assessment guidance for Superfund default scenarios | Sediment and soil | Resident/recreator | 50 (adult; commercial/industrial); 100 (adult; residential/agricultural); 100 (child; mean); 200 (child; upper boundary of estimate of mean) | 63, 68 | 9 (50th percentile tenure); 30 (90th percentile tenure); 70 (lifetime) | 365 days/yr multiplied by fraction ingested from contaminated source (residential); 7 days/yr or estimated based on local meteorological factors (recreational swimming [74]); 12 days/yr (recreational swimming [63]) |
| 52 | Human health protective concentration level | Sediment | Recreator | 191 (child); 100 (adult) | 63 | 6 (child); 24 (adult) | 39 |
| 79 | Guidance for State of Virginia (also cited by USEPA) | Sediment | Recreator/trespasser | 25 (child); 10 (adult) | 66 | 6 (child); 24 (adult) | 24 (trespasser); 95 (recreator) |
| 24 | Peer-reviewed recommended distributions | Soil | Resident | 21 (child; mean); 110 (child; 95th percentile) | 12 | Function of age | |
| 37 | Guidance for State of Oregon | Soil | Resident | Lognormal (mean = 60, SD = 67) (child); lognormal (mean = 57, SD = 18) (adult) | 12, 13, 19 | Function of age | Triangular (mode = 5, maximum = 150) (recreational swimming) |
| Site-specific assessment | |||||||
| 3 | Agency for Toxic Substances and Disease Registry health consultation | Calcasieu Estuary in Calcasieu Parish, LA (sediment) | Recreator | 100 (adult); 200 (child) | 68 | Adult, 18 to 70 yrs old; child, 6 to 17 yrs old | 184 |
| 2 | Agency for Toxic Substances and Disease Registry health consultation | Former wood treatment facility in Texarkana, Bowie County, TX (sediment) | Trespasser | 100 (adult); 150 (child, elementary-school age); 200 (child, preschool age) | 68 | 6 (child); 30 (adult) | 350 |
| 4 | Peer-reviewed risk assessment | Meuse River, The Netherlands (sediment) | Recreator | 1,000 (child); 350 (adult) | 9 | 30 | |
| 25 | Peer-reviewed risk assessment | Little Bay, Queens, NY (sediment) | Future child and adult recreators | 50 (child); 12.5 (adult) | 63 | 6 (child); 30 (adult) | 52 |