Quantified outdoor micro-activity data for children aged 7-12-years old.

Area of Science:

• Environmental Health
• Pediatric Health
• Behavioral Science

Background:

• Accurate estimation of aggregate exposure and risk necessitates detailed data on dermal contact and mouthing behaviors.
• Understanding children's contact behaviors is crucial for assessing potential health risks from environmental exposures.

Purpose of the Study:

• To quantify dermal contact and mouthing activity in children aged 7-12 years using micro-level activity time series (MLATS).
• To evaluate differences in these behaviors based on age and gender.
• To compare observed contact frequencies with current regulatory recommendations.

Main Methods:

• Analysis of micro-level activity time series (MLATS) data from 18 children aged 7-12 years, who were videotaped during outdoor play.
• Transcription of video footage using Virtual Timing Device (VTD) software.
• Calculation of hand and mouth contact frequency, hourly duration, and median duration for 16 object categories.

Main Results:

• Median mouthing frequencies were 12.6 events/h (hands) and 2.6 events/h (non-dietary objects).
• Median hourly mouthing duration was 0.4 min/h (hands) and 0.1 min/h (objects).
• Overall hand contact frequency was 537.3 events/h with an hourly duration of 81.8 min/h; contact frequencies exceed regulatory recommendations.

Conclusions:

• No significant differences in mouthing activity were found between genders or age groups.
• Female children showed more frequent and longer hand contacts with surfaces.
• Observed contact frequencies in children aged 7-12 years are higher than current regulatory guidelines, highlighting potential exposure concerns.