TR 079 – Exposure Factors Sourcebook for European Populations (with Focus on UK Data)

TR 079 : Exposure Factors Sourcebook for European Populations (with Focus on UK Data) | June 2001

Risk assessment includes elements of exposure, hazard, and dose-response. The exposure component is calculated using variables that represent the concentration in a given media (i.e., soil, water, air, food) and human contact with the media. Exposure factors are the variables used to estimate the human contact portion of the exposure calculation. Exposure factors include variables related to human activities (e.g., time indoors vs. outdoors, weekly work hours) and physiological parameters (e.g., inhalation rates, body weight).

This document summarises available exposure factor data for use in risk-based decision making. It updates and builds upon other available compendia of exposure factor data - the AIHC Exposure Factors Sourcebook (EFS) and the USEPA Exposure Factors Handbook (EFH). Whereas the EFS and EFH have focused on US data, this document focuses on data specific to Europe, in particular the UK. The exposure factors selected for inclusion were those most relevant to risk-based decision making for contaminated land sites. The factors and data presented, however, are applicable to exposure assessment and risk-based decision making in general. The information summarized in this document includes:

• Physiological Parameters
  (Adult Body Weight, Child Body Weight, Total Skin Surface Area, Surface Area of Specific Body Parts, Life Expectancy);
• Time-Activity Patterns
  (Weekly Work Hours, Daily Hours at Home/Away, Time Indoors/Outdoors, Daily School Hours, School Time Indoors/Outdoors, Outdoor Recreation, Shower Duration, Employer Tenure, Residential Tenure, School Tenure);
• Receptor Contact Rates
  (Soil Ingestion Rates, Soil Adherence to Skin, Inhalation - Short-term Rate, Inhalation - Long-term Rate, Food Consumption Rates, Home Grown Vegetable and Fruit Consumption Rate, Fish and Shellfish Consumption Rate, Meat and Beef Consumption Rate, Drinking Water Consumption Rate, Breast Milk Consumption Rate).

Exposure scenarios can differ widely and therefore the averages and distributions presented in this document may not be the best representation for all possible exposure scenarios. Best judgement should be used in selecting the values most appropriate for a given scenario. A section on good exposure assessment practices is also included in the document. The cited references may also serve as useful sources of additional information on exposure factors and exposure assessment.

Data gaps have been identified and whilst this document includes data for European countries in general, its primary focus is the UK. Future expansion of additional data for other countries would be useful for improving the accuracy of exposure assessments for other European populations.