ACRONYMS

A

Acre

ADI

Acceptable Daily Intake; mg/kg/day Used by World Health Organization, was used by EPA before the term Reference dose (RfD)

AI

Active Ingredient; The chemical compound in a pesticide formulation used to produce the desired pesticidal effect in the target species.

AQR

Aquatic Risk Quotient; The ratio used by EPA Office of Pesticides Programs (OPP) for evaluating ecological risk posed by pesticides in surface water. The ratio is of the highest estimated concentration in water (mg/L (ppm) or ug/L (ppb))/lowest LC50 reported for the compound in question (mg/L (ppm) or ug/L (ppb)) .

Bti

Bacillus thuringiensis variety israelensis

bw

body weight

CAS

Chemical Abstract Service; CAS # is a unique identifier for a given chemical structure

ChE

Cholinesterase; includes acetylcholinesterase (AChE) and pseudocholinesterase (PsChE)

cw

Cold water fish

DDVP

Dichlorovinyl dimethyl phosphate

EC

Emulsifiable Concentrate; refers to a pesticide formulation not to be confused with EC50; median effect concentration

EC50

Median Effect Concentration; The concentration of a chemical in water (mg/L (ppm) or ug/L (ppb)) , soil/sediment (mg/L (ppm) or ug/L (ppb)), air (mg/M3) that caused effects other than death in 50 % of exposed organisms in toxicity tests. Values are typically expressed as a time-dependent value, reflecting the duration of the test exposure (e.g., 96Hr-LC50).

ED50

Median Effective Dose; The dose of a compound that produces effects other than death in 50% of exposed test organisms. Dose values are often used with non-aquatic species (birds, humans and other mammals) because it indicates the quantity of a material introduced directly into the body during toxicity tests. Dose rates are typically reported as mg contaminant /kg body weight per day (mg/kg/day).

EEC

Estimated (or Expected) Environmental Concentration; The concentration (mg/L (ppm) or ug/L (ppb)) of a material estimated as being likely to occur in environmental media to which organisms may be exposed as a result of manufacture, use and disposal.

EFED

EPA's Environmental Fate and Effects Division

em

Estuarine and marine organisms

EPA

Environmental Protection Agency

H

Henry's Law constant; A measure of the tendency for a compound to partition from water into air.

HSDB

Hazardous Substances Data Base from the National Library of Medicine available through TOXNET; website = http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?HSDB

IARC

International Agency for Research on Cancer

inv

Freshwater invertebrates

ITU

International Units; used to describe formulations of Bacillus thuringiensis israelensis and Bacillus sphaericus. There is a measurement of potency in the units.

Kd

Soil-water adsorption coefficient. A more general version of Koc, calculated by measuring the distribution of substances between soil or sediment and water.

kg

Kilograms

Koc

Organic carbon-water partition coefficient A measure of the tendency for organic hydrophobic chemicals to sorb primarily to the organic carbon present in soils or sediment. A high value indicates a strong tendency for adsorption to soil or sediment, rather than remain dissolved in soil solution (or pore water). Strongly adsorbed molecules will not leach or move unless the soil particle to which they are adsorbed moves (as in erosion). Koc of less than 500 indicates little or no adsorption and a potential for leaching.

Kow

Octanol-water partition coefficient. A measure of hydrophobicity or the tendency of a compound to partition from water to organic media such as lipids, waxes and natural organic matter such as humin or humic acids. The higher the value, the greater the tendency for a compound to associate with organic matter rather than water. Often used to determine the tendency for organic compounds to bioaccumulate in the lipids of exposed biota.

lbs

Pounds

LC50

Median Lethal Concentration; The concentration of a chemical in water (mg/L (ppm) or ug/L (ppb)), soil/sediment (mg/L (ppm) or ug/L (ppb)) , air (mg/M3) that is lethal to 50 % of exposed organisms in toxicity tests. Values are typically expressed as a time-dependent value, reflecting the duration of the test exposure (e.g., 96Hr-LC50).

LD50

Median Lethal Dose ; The dose of a compound that is estimated to be lethal to 50% of exposed test organisms. Dose values are often used with non-aquatic species (birds, humans and other mammals) because it indicates the quantity of a material introduced directly into the body during toxicity tests. Dose rates are typically reported as mg substance / kg body weight per day, (mg/kg/day).

LEL

Lowest Effect Level

LOAEL

Lowest Observed Adverse Effect Level; The lowest dose rate of a substance used in a toxicity test that has a statistically significant adverse effect on the exposed population of test organisms compared with the controls (e.g., 50% mortality in the test population versus 10% mortality in controls). Values are generally used with non-aquatic species (birds, humans and other mammals) because it indicates the quantity of a material introduced directly into the body during toxicity tests (reported as mg substance / kg body weight per day, (mg/kg/day)).

LOC

Level of Concern; A compound-specific benchmark level (acceptable risk level) established for comparison with measured or estimated exposure levels to determine risk. Benchmarks may be based on most sensitive observed effects in the most sensitive species tested for the compound in question. When data are limited, the LOC may be an LC50 multiplied by safety factors of 0.1 or less to account for uncertainty in the available data.

LOEC

Lowest Observed Effect Concentration; The lowest concentration (mg/L (ppm) or ug/L (ppb)) of a substance used in a toxicity test that has a statistically significant adverse effect on the exposed population of test organisms compared with the controls (e.g., 50% mortality in the test population versus 10% mortality in controls).

mg

Milligrams

MMF

Monomolecular film

mmHG

Millimeters of mercury used as a measure of vapor pressure, the lower the vapor pressure the less volatile the compound

modEXP

Modified Exposure factor; Surrogate for the exposure factor in terms of mg/Acre.

modMOE

Modified Margin of Exposure; No Observable Adverse Effect Level divided by modified exposure factor (mg/Acre) The higher the modMOE the less the relative risk .

MOE

Margin of Exposure; No Observable Adverse Effect Level divided by Exposure The higher the MOE the less the risk.

modRQ

Modified Risk Quotient; modified exposure factor (mg/Acre)/median lethal dose (LC 50 ); The lower the modRisk Quotient (RQ) the less the relative risk .

NOAEL

No Observed Adverse Effect Level; The highest does in an experiment that does not produce an observable adverse effect (reported as mg substance / kg body weight per day, (mg/kg/day)).

NOEC

No Observed Effect Concentration; The highest concentration (mg/L (ppm) or ug/L (ppb)) of a compound in a test that has no statistically significant adverse effect on the exposed population of test organisms as compared with controls.

NOEL

No Observed Effect Level The dose or exposure level at which no effects can be detected (reported as mg substance / kg body weight per day, (mg/kg/day)).

OP

Organophosphate insecticides

Pa

Pascal used as a measure of vapor pressure; the lower the vapor pressure the less volatile the compound

PBO

Piperonyl butoxide; synergist used with pyrethrins and syntheitic pyrethroids

POE

Poly(oxy-1,2-ethandiyl), a-isooctyadecyl-?- hydroxl

ppb

Parts per billion (ug/kg diet or mg/L water)

ppm

Parts per million (mg/kg diet or mg/L water)

pts

Pints

RfD

Reference dose; mg/kg/day

RQ

Risk Quotient Estimated Environmental Concentration/median lethal dose (LC 50 ); The lower the Risk Quotient (RQ) the less the risk .

RQ

Risk Quotient; The ratio of a measured or estimated level of exposure (dose or concentration) to a benchmark dose or concentration. Also known as the hazard quotient (HQ) or hazard index (HI) in ecological and human health risk assessment. Values greater than 1.0 indicate risk of adverse effects for sensitive members of the exposed population.

RTU

Ready to use

SYN

Synergists; Compounds used to inhibit enzyme function to increase the activity of the pyrethroids.

T1/2

Half Life; The time required for half of the residue to lose its analytical identity whether through dissipation, decomposition, metabolic alteration, or other factors (i.e., for the concentration of a pesticide in an environmental medium to be reduced by one-half).

TGAI

Technical Grade Active Ingredient

TL 50

Median Threshold Limit

ULV

Ultra Low Volume; A spray application method that uses low volumes (1/2 gallon or less per acre) of undiluted active ingredient.

WNV

West Nile Virus

ww

Warm water fish

RISK ASSESSMENT DEFINITIONS

Absolute risk

Probability of a toxic effect given a specific set of exposure parameters.

Acceptable risk

Cutoff point where an agency will step in to reduce exposure to minimize risks.

Levels of Concern (LOC)

EPA's acceptable risk criteria for the Risk Quotient calculations .

Margin of Exposure (MOE)

No Observable Adverse Effect Level divided by Exposure; The higher the MOE the less the risk.

Relative risks analysis

A method of comparing the risks from exposure to one compound with the risks associated with exposure to another, given a set of similar exposure parameters.

Risk Quotient (RQ)

Estimated Environmental Concentration/median lethal dose (LC 50 ); The lower the Risk Quotient (RQ) the less the risk .