title: Quantified outdoor micro-activity data for children aged 7-12-years old.
abstract: Estimation of aggregate exposure and risk requires detailed information regarding dermal contact and mouthing activity. We analyzed micro-level activity time series (MLATS) of children aged 7-12 years to quantify these contact behaviors and evaluate differences by age and gender. In all, 18 children, aged 7-12 years, were videotaped while playing outdoors. Video footage was transcribed via Virtual Timing Device (VTD) software. We calculated the hand and mouth contact frequency, hourly duration and median duration of contact with 16 object categories. Median mouthing frequencies were 12.6 events/h and 2.6 events/h for hands and non-dietary objects, respectively. Median hourly mouthing duration was 0.4 min/h and 0.1 min/h with hands and objects. Median mouthing contact duration was 1 s and 1.5 s with hands and objects, respectively. The median object contact frequency for both the hands combined was 537.3 events/h with an hourly contact duration of 81.8 min/h and a median contact duration of 3 s. There were no significant differences in the mouthing activity between genders or age groups. Female children had longer and more frequent hand contacts with several surface types. Age was negatively correlated with hand contacts of floor and wood surfaces. Contact frequencies in this study are higher than current regulatory recommendations for this age group.
authors: Environmental Health Sciences, Mel and Enid Zuckerman College of Public Health, University of Arizona, Tucson, Arizona, USA. pbeamer@email.arizona.edu
authors: Paloma I
authors: PI
authors: Beamer
authors: Catherine E
authors: CE
authors: Luik
authors: Robert A
authors: RA
authors: Canales
authors: James O
authors: JO
authors: Leckie
mesh_terms: D000367:Age Factors; D002648:Child; D002652:Child Behavior; D002675:Child, Preschool; D004781:Environmental Exposure / Q000032:analysis*; D004784:Environmental Monitoring / Q000379:methods; D004785:Environmental Pollutants; D005260:Female; D006801:Humans; D008297:Male; D010988:Play and Playthings; D011786:Quality Control; D012737:Sex Factors; D013997:Time Factors; D014743:Videotape Recording
chemical_list: D004785:Environmental Pollutants