title: Factors associated with the seasonality of blood lead levels among preschool Wisconsin children.
abstract: BACKGROUND
  Aggregate blood lead testing data for Wisconsin children younger than age 6 exhibit seasonal trends in both average blood lead levels and in the percent of those tested and found to have blood lead levels in excess of the 10 mcg/dL threshold for poisoning. Blood lead levels and poisoning rates typically peak during the late summer and early fall months, and are at their minimum during the late winter.
  
  
  METHODS
  Blood test data was analyzed to determine variations by month and age.
  
  
  RESULTS
  Seasonal variations are evident even among the very young: infants younger than 10 months who likely have limited opportunity to encounter lead hazards within their home or in the outdoor soil. Seasonal periodicity is most evident among infants who reside in very urban and very rural communities. The observed seasonal periodicity might be associated with the seasonal availability of lead within the children's environment. Particulate matter data measured at several ambient air quality monitoring stations exhibit a similar periodic seasonality, suggesting a possible relationship between blood lead levels and the availability of dust and airborne particulates during the summer months.
  
  
  CONCLUSIONS
  Clinicians should consider the seasonality of blood lead levels when scheduling tests and interpreting test results.
authors: Wisconsin Childhood Lead Poisoning Prevention Program (WCLPP), Wisconsin Department of Health Services (DHS), Madison, WI 53702, USA. jeffrey.havlena@wisconsin.gov
authors: Jeff
authors: J
authors: Havlena
authors: Marty S
authors: MS
authors: Kanarek
authors: Margie
authors: M
authors: Coons
mesh_terms: D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007854:Lead / Q000097:blood*; D008297:Male; D012621:Seasons; D014922:Wisconsin
chemical_list: D007854:Lead