TABLE 2.

Survey of recent risk assessment parameter selections utilized for risk assessment of incidental ingestion resulting from direct contact with sediment

ReferenceType of guidance or assessmentLocation and medium(-a)ScenarioSediment ingestion rate (mg/day)Reference(s) for ingestion rateExposure
Duration (yrs)Frequency (days/yr)
Generic guidance
    74Risk assessment guidance for Superfund default scenariosSediment and soilResident/recreator50 (adult; commercial/industrial); 100 (adult; residential/agricultural); 100 (child; mean); 200 (child; upper boundary of estimate of mean)63, 689 (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])
    52Human health protective concentration levelSedimentRecreator191 (child); 100 (adult)636 (child); 24 (adult)39
    79Guidance for State of Virginia (also cited by USEPA)SedimentRecreator/trespasser25 (child); 10 (adult)666 (child); 24 (adult)24 (trespasser); 95 (recreator)
    24Peer-reviewed recommended distributionsSoilResident21 (child; mean); 110 (child; 95th percentile)12Function of age
    37Guidance for State of OregonSoilResidentLognormal (mean = 60, SD = 67) (child); lognormal (mean = 57, SD = 18) (adult)12, 13, 19Function of ageTriangular (mode = 5, maximum = 150) (recreational swimming)
Site-specific assessment
    3Agency for Toxic Substances and Disease Registry health consultationCalcasieu Estuary in Calcasieu Parish, LA (sediment)Recreator100 (adult); 200 (child)68Adult, 18 to 70 yrs old; child, 6 to 17 yrs old184
    2Agency for Toxic Substances and Disease Registry health consultationFormer wood treatment facility in Texarkana, Bowie County, TX (sediment)Trespasser100 (adult); 150 (child, elementary-school age); 200 (child, preschool age)686 (child); 30 (adult)350
    4Peer-reviewed risk assessmentMeuse River, The Netherlands (sediment)Recreator1,000 (child); 350 (adult)930
    25Peer-reviewed risk assessmentLittle Bay, Queens, NY (sediment)Future child and adult recreators50 (child); 12.5 (adult)636 (child); 30 (adult)52