a.i. (Active Ingredient)
The chemical or substance in a pesticide product intended to kill, repel, attract, mitigate or control a pest or that acts as a plant growth regulator. The other ingredients in the formulation are referred to as inerts.

Absorbed Dose
The amount of a substance penetrating across the absorption barriers of an organism, via either physical or biological processes. Synonymous with internal dose.

Aggregate Exposure
The amount of a single substance available for interaction with metabolic processes or biologically significant receptors from multiple routes and pathways of exposure.

Aggregate Exposure Assessment
A process for developing an estimate of the extent of exposure of a defined population to a given chemical by all relevant routes and from all relevant sources (pathways).

Blended Commodities
Foods or food forms for which large-scale blending and mixing occurs at some time in the food chain to the consumer.

Crop Groupings
The Raw Agricultural Commodities recorded in the NHANES/FCID databases are divided into groups according to similar morphologies (type, size, texture, etc.). Residue data generated on a few designated representative commodities can then be translated to the others in the crop group assuming use patterns are similar.

Cumulative Exposure Assessment
A process for developing an estimate of the extent to which a defined population is exposed to two or more chemicals which share a common mechanism of toxicity by all relevant routes and from all relevant sources (pathways)

Cumulative Risk
The likelihood for the occurrence of an adverse health effect resulting from all pathways and routes of exposure to substances sharing a common mechanism of toxicity.

This approach uses point estimates, for example, single maximum values or average values, to represent input variables in an exposure model.

Dislodgeable Residues
The portion of a pesticide that is available for transfer from a pesticide treated surface.

Event Allocation
The frequency of residential pesticide use is specified in this CARES module.

Contact of a substance with the outer boundary of an organism. Exposure is quantified as the concentration of the agent in the medium in contact integrated over the time duration of that contact.

Exposure Assessment
The qualitative or quantitative determination or estimation of the magnitude, frequency, duration, and rate of exposure of an individual or population to a chemical. CARES NG enables the user to run two types of exposure assessments:

  1. Dietary assessment: estimation of the exposure to a chemical through the consumption of foods and drinking water
  2. Residential assessment: estimation of the exposure to a chemical through the usage of pesticidal products

Exposure Scenario
A combination of facts, assumptions, and inferences that define a discrete situation or activity where potential exposures may occur.

Field Trials
Residue studies conducted on crops (usually by registrants) at maximum label rates and minimum PHI’s to determine tolerance levels for registration.

FCT (Fraction Crop Treated)
An estimate of the acreage under cultivation that is actually treated with the pesticide at least once. It is expressed as a fraction of the total acreage in the US for that crop.

Index Chemical
The chemical selected as the basis for standardization of toxicity of components in a mixture. The index chemical should have a clearly defined dose-response relationship

HI (Hazard Index)
The sum of each exposure divided by it’s RfD

LOD (Limit of Detection)
Statistical method for handling non-detectable pesticide residues in food. The level at or below which residues cannot be detected for that method.

LOQ (Limit of Quantification)
Statistical method for handling non-quantifiable residues in food. The level below which residues cannot be reliably quantified for that method.

MOE (Margin of Exposure)
The point of departure divided by a human environmental exposure of interest, actual or hypothetical.

A compound used to control a pest. A pest can be an insect, plant or any organism, such as a mold or bacteria.

Residue concentration
The amount of the original chemical (known as parent) or breakdown products (known as metabolites) that remain on the medium of concern (i.e. food, drinking water, skin, etc.).

POD (Point of Departure)
Point on the dose-response curve where each chemical’s response is close to or within the background level of response, in other words, the dose at which effects from a pesticide are first distinguishable. Depending on the data available and the purpose of the analysis, there are differing procedures for estimating points of departure.

PAD (Population Adjusted Dose)

The reference dose of a pesticide adjusted for the FQPA safety factor.

Post-Application Exposure
Exposures from any residues that remain in and around the home after a pesticide is used.

Modification Factors
Factors that account for increase or decrease in residues in foods or in water due to preparation (i.e. washing, cooking, peeling) or treatment (i.e. filtration, chlorination).

Przm-3 and EXAMS-II are both US EPA environmental fate models that simulate fieldscale pesticide transport for Tier 2 screening assessments. The Pesticide Root Zone Model (PRZM-3) simulates leaching and run-off from a field; the output from PRZM is linked to the Exposure Analysis Modeling System (EXAM-II) to simulate pesticide concentrations in surface water.

RAC (Raw Agricultural Commodity)
Foods broken down into their simplest components are composed of the RACs. This is the crop/commodity that EPA registers and assigns tolerances (i.e., wheat, corn, apples, tomatoes, etc.) from field trial data.

Residential Exposure
EPA uses this term to refer to any exposure to any person who lives in a home beyond the diet and outside the occupational setting. Exposures that occur as a result of pesticide applications in schools, parks, and day care centers are included under this term.

RfD (Reference Dose)
The NOAEL divided by the UF.

Sensitivity Analysis
Effect of changing the value of single variables in the risk assessment to see the magnitude of the change to the outcome.

SOP (Standard Operating Procedures)
Methods developed by the agency to address over different exposure scenarios for residential exposure assessment.

Time Frames

  • Chronic: average RAC consumption / product usage for each selected population and the average residue value for each commodity / product.
  • Cancer: average food and average water and residential exposures relevant for lifetime assessment
  • Acute: estimate of exposure from a pesticide or several pesticides with a common mechanism of toxicity during a one day (24 hour) time period.
  • Multi-day: for each individual, the daily exposure to the relevant RACs / residential products is calculated for each of the 365 days. The n-day average combines n-day distributions over the 365 days of daily food consumption and product usage data with a single value (toxicological endpoints, average values, etc.) or random samples from the residue data.
  • Within-day: exposure analyses at the level of eating occasion instead of daily. The exposure level is refined within the day based on a user-defined decay factor for the pesticide(s). The intervals can vary from one minute to one hour