Legacy lead arsenate soil contamination at childcare centers in the Yakima Valley, Central Washington, USA.
BACKGROUND
From the early 1900s to the 1950s, Yakima Valley orchards were commonly treated with lead arsenate (LA) insecticides. Lead (Pb) and arsenic (As) soil contamination has been identified on former orchard lands throughout Central Washington and pose a threat to human health and the environment.


OBJECTIVE
The levels of Pb and As in soil and interior dust at participating childcare centers in the Upper Yakima Valley (Yakima County), Washington were sampled to explore exposure potential for young children.


METHODS
Childcare center soils were collected from two soil depths, homogenized, and analyzed in bulk by a field-portable X-ray fluorescence spectrometer (XRF). Interior dust wipes samples were collected from at least two locations in each facility. All soil samples >250 mg/kg Pb and/or >20 As mg/kg were sieved to 250 μm, tested by XRF a second time, and analyzed via acid digestion and inductively coupled plasma mass spectrometry (ICP-MS) analysis.


RESULTS
Bulk and sieved XRF results, as well as ICP-MS to XRF results were strongly correlated. Maximum Pb and As XRF results indicated that 4 (21%) and 8 (42%) of the 19 childcare centers surveyed exceeded the regulatory standard for Pb and As, respectively. Historic land use was significantly associated with elevated Pb and As levels. Interior dust loadings were below United States Environmental Protection Agency (EPA) guidelines.


CONCLUSIONS
Childcare centers are areas of intensive use for children and when coupled with potential residential exposure in their homes, the total daily exposure is a potential hazard to children.
Environmental Science Program, University of Idaho, Moscow, ID, USA. Electronic address: durk1213@vandals.uidaho.edu.
Jenna
J
Durkee
Environmental Science Program, University of Idaho, Moscow, ID, USA.
Casey
C
Bartrem
Environmental Science Program, University of Idaho, Moscow, ID, USA; School of Food Science, University of Idaho, Moscow, ID, USA; Biological Engineering, University of Idaho, Moscow, ID, USA.
Gregory
G
Möller
D000293:Adolescent; D001149:Arsenates / Q000032:analysis*; D001151:Arsenic / Q000032:analysis*; D002648:Child; D002656:Child Day Care Centers; D002675:Child, Preschool; D004391:Dust / Q000032:analysis; D004787:Environmental Pollution / Q000032:analysis*; D006798:Housing; D006801:Humans; D007223:Infant; D007306:Insecticides / Q000032:analysis* / Q000737:chemistry; D007854:Lead / Q000032:analysis*; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000032:analysis*; D014481:United States; D014484:United States Environmental Protection Agency; D014861:Washington
D001149:Arsenates; D004391:Dust; D007306:Insecticides; D012987:Soil; D012989:Soil Pollutants; D007854:Lead; C045846:lead arsenate; D001151:Arsenic
Arsenic; Childcare centers; Children's health; Lead; Pesticide; Risk assessment