What Should Be Included In The Exposure Profile (Text Version)

The exposure profile describes and documents the findings of the exposure characterization. Decide whether each statement below is correct in what it says about what the exposure profile should do before you read the answer.

Provides toxicology data.
No. Toxicology data is provided in the effects profile.

Describes the source.
Yes! The exposure profile needs to clearly describe the cause, or source, of the stressor whose impact is being assessed.

Identifies receptors.
Yes! These were determined during problem formulation. For example, if paving a small area of a field will not have a significant impact on the insect population, but may dangerously reduce the population of a sensitive indigenous plant, the assessment needs to clearly identify that species, one of the receptors with which it is concerned.

Describes exposure pathways.
Yes! In many cases, exposure can occur through a number of pathways. In such cases, it can be useful to rank the exposure pathways, in order of their contribution to total exposure.

Describes how exposure can vary depending on receptor attributes or stressor levels.
Yes! Variability can be described by using a distribution or by describing where a point estimate is expected to fall on a distribution. Cumulative-distribution functions (CDFs) and probability-density functions (PDFs) are two common presentation formats. The point-estimate/descriptor approach is used when there is not enough information to describe a distribution. Descriptors that are commonly used include central tendency, high-end, and bounding estimates.

Describes important uncertainties.
Yes! Concerning uncertainty, the profile should (1) identify key assumptions and describe how they were handled, (2) discuss (and quantify, if possible) the magnitude of sampling and/or measurement error, (3) identify the most sensitive variables influencing exposure, and (4) identify which uncertainties can be reduced through the collection of more data.

Reaches a conclusion about the likelihood that exposure will occur.
Yes! All of the information included in the correct selections you've made is synthesized to determine the likelihood for exposure to occur.

Evaluates management options.
No. This occurs in the planning and communication phases.

Describes stressor fate and transport in the ecosystem.
Yes! To determine whether exposure will occur, we need to know how the stressor behaves in the environment.

Makes a risk calculation.
No. This is an important part of risk assessment but belongs in Risk Characterization.

Describes the intensity and spatial and temporal extent of co-occurrence or contact.
Yes!

Relevant guidelines section(s): 4.2.2