Glossary of terms for environmental water monitoring for pesticides

Purpose of the glossary

This glossary was prepared by the Pest Management Regulatory Agency to assist while reading any environmental water monitoring content published online. It defines or explains terms that are commonly used in this area of expertise.

Note: The glossary provides explanations for different words we use online. These are not legal definitions.

Acaricide
Pesticide used to control mites.
Active ingredient (AI)
The component in a pest control product that kills/controls the target pest. The AI includes any substance, or group of substances as specified by the Pest Management Regulatory Agency, that prevents, mitigates, destroys, or repels any pest; or that acts as a plant growth regulator, desiccant, defoliant, or nitrogen stabilizer.
Acute exposure
A single exposure to a substance, typically lasting not longer than 24-48 hours.
Acute fish Aquatic Life Reference Value (ALRV)
An estimate of short-term concentrations of a pesticide below which fish are unlikely to experience severe adverse effects such as death.
Acute Human Health Reference Value (HHRV)
A person drinking water containing the pesticide at or below this value is unlikely to experience health effects. Short-term HHRVs should be used when exposure is limited to one day.
Acute invertebrate Aquatic Life Reference Value (ALRV)
An estimate of short-term concentrations of a pesticide below which aquatic invertebrates are unlikely to experience severe adverse effects such as death.
Acute toxicity
The potential for a substance to result in adverse effects to an organism resulting from an acute exposure. The effect can occur shortly after exposure or be delayed.
Analyte
A chemical substance or material that is the subject of chemical analysis.
Analytical standard
A compound of high purity and known concentration to be used as a calibration standard for a given assay or to determine unknown concentrations.
Analytical validation
Documented evidence (through laboratory studies) that the procedure's performance characteristics meet the requirements for its intended use. It covers quality, reliability and results consistency. Any change in equipment or instrumentation or premises may call for revalidation of the analytical methods.
Ancillary data
Additional information that helps with interpreting data such as water flow, pH, Total dissolved solids, cropping information, pesticide use, etc.
Antimicrobial pesticide
Pesticide intended to disinfect, sanitize, reduce, or mitigate growth or development of microbiological organisms; or protect inanimate objects, industrial processes or systems, surfaces, water, or other chemical substances from contamination, fouling, or deterioration caused by bacteria, viruses, fungi, protozoa, algae or slime.
Aquatic biota
All organisms that, as part of their natural life cycle, live in or on waters.
Aquatic Life Reference Value (ALRV)
An estimate of the concentrations below which pesticides are not expected to present a risk of concern for freshwater organisms.
Aquatic non-vascular plant
Primitive plant lacking specialized vascular tissues (water/food conducting tissues, true leaves, roots and stem) that is found in damp and moist areas. Examples: algae, moss and liverworts.
Aquatic vascular plant
Aquatic plant growing in or near water, it may be emergent (above the water's surface), submerged (below the water's surface), or floating. Examples: cattails, water lilies and pond weeds/duckweed.
Auto-sampler
Device that automatically collects a specific volume of water (individual bottles) at a specific depth based on time or other water parameter (for example, conductivity, flow rate, pH, etc.).
Best management practice (BMP)
Agricultural practice that reflects current knowledge about conserving soil and water without sacrificing productivity. Developed by scientists and agronomists (in partnership with different organizations), these practices reduce the environmental impact of agriculture.
Bioaccumulation
Accumulation over time of a substance in a living organism or through the food chain. In an organism, it occurs when a substance is absorbed at a rate faster than that which it is lost or eliminated by catabolism and excretion.
Bioavailable
The presence of a substance in a form that organisms can take up. The bioavailable fraction of a pesticide may cause adverse effects under certain conditions.
Bounding box
Used in mapping to describe the spatial location of a site or group of sites. Commonly used to protect privacy of landowners.
Brook
A small stream.
Chronic effect
An effect which occurs as a result of repeated or long-term exposure to a substance.
Chronic exposure
Continuous or repeated exposure to a substance over a long period of time.
Chronic fish Aquatic Life Reference Value (ALRV)
An estimate of long-term concentrations of a pesticide below which fish are unlikely to experience adverse effects. Small exceedances of the chronic ALRVs for short periods of time are not expected to cause harm.
Chronic Human Health Reference Value (HHRV)
A person is unlikely to experience adverse health effects from drinking water containing a pesticide at or below the long-term HHRV over a lifetime. Small exceedances above the long-term value for short periods of time are not expected to cause harm.
Chronic invertebrate Aquatic Life Reference Value (ALRV)
An estimate of long-term concentrations of a pesticide below which aquatic invertebrates are unlikely to experience adverse effects. Small exceedances of the chronic ALRVs for short periods of time are not expected to cause harm.
Chronic toxicity
The potential for a substance to result in adverse effects to an organism resulting from repeated or extended exposure relative to the lifespan of the organism.
Creek
A natural stream of water normally smaller than, and often a tributary to, a river (see stream definition below).
Detection
Distinguishing a certain amount of a pesticide in a water sample that is higher than the method detection limit (minimum detectable amount).
Detection frequency
The percentage of individual measurable pesticide concentrations above the method detection limit (MDL).
Drainage basin
Land area where precipitation runs off into streams, rivers, lakes and reservoirs. It is a land feature that can be identified by tracing a line along the highest elevations between two areas on a map, often a ridge.
Effective concentration 50 percent (EC50)
Concentration of material in water estimated to cause a specified non-lethal or lethal effect in 50% of test organisms.
Endocrine disruptor
Chemical compound that alters the normal functioning of the endocrine (or hormonal) system, causing negative health and/or environmental impacts.
Environmental fate
Indications of what happens to a substance once it enters the environment and its behaviour in soil, water and air, potential uptake by plants or animals, and the potential for bioaccumulation in organisms. Determination of fate considers physical and chemical properties, transformation processes, mobility and field studies.
Exceedance
A determination that the concentration of a pesticide in a water sample is greater than an Aquatic Life Reference Value or a Human Health Reference Value.
Exceedance frequency
The percentage of pesticide concentrations above the lowest Human Health Reference Value or Aquatic Life Reference Value in a given sample. Small exceedances of the chronic value for short periods of time are not expected to cause harm.
Fungicide
Pesticide used to control fungi.
Grab sample
Individual volume of water taken at a specific time. Typically sampled using a pole or weighted sampler or by wading in the water course.
Groundwater
  1. Water that flows or seeps downward and saturates soil or rock, supplying springs and wells. The upper surface of the saturated zone is called the water table.
  2. Water stored underground in rock crevices and in the pores of geologic materials that make up the Earth's crust.
Half-life
The time required for a substance to reduce to half of its initial concentration.
Hazardous concentration 5 percent (HC5)
HC5 is the fifth percentile estimate of a species distribution model. The value represents the concentration of a substance at which the endpoint for 95% of species is not expected to be exceeded.
Herbicide
Pesticide used to control plants.
Human Health Reference Value for pesticides in drinking water sources (HHRV)
A value that represents the concentration of a pesticide in drinking water sources below which a person is unlikely to experience adverse health effects.
Inhibiting concentration 50 percent (IC50)
Concentration of test substance or material that causes 50% impairment in a quantitative biological function.
Insecticide
Pesticide used to control insects.
Lake
A large water body where surface-water runoff (and potentially some groundwater) has accumulated in a land depression, relative to the surrounding countryside.
Lethal concentration 50 percent (LC50)
Concentration of test substance or material that is estimated to be lethal to 50% of the test organisms.
Lethal dose 50 percent (LD50)
Amount of material, given all at once, which causes the death of 50% of the test organisms.
Limit of detection (LOD)
Minimum amount of an analyte that can be detected reliably and distinguished from a known and characterized background with a given level of confidence. The LOD establishes a baseline detection value under optimal standardized conditions.
Limit of quantification (LOQ)
Lowest amount of an analyte that can be reliably detected with acceptable precision and accuracy as required by data quality standards.
Metabolism
The chemical changes that take place in a cell or an organism. These changes make energy and the materials cells and organisms need to grow, reproduce, and stay healthy. Metabolism also helps get rid of toxic substances.
Metabolite
Intermediate or final product produced when a pesticide is broken down by metabolism.
Method detection limit (MDL)
Minimum amount of a substance that can be measured and reported with 99% confidence that the amount of analyte is greater than zero and is determined from analysis of a sample in a given matrix containing the analyte.
Microgram per liter (ug/L)
The concentration of a substance at which one millionth of a gram of it is present in a volume of one liter of liquid.
Nano pesticide
Pesticide that contains chemical toxins in nanoscale materials/nanoparticles and having specific characteristics (such as shape and size) as well as unique chemical, physical and biological properties.
National-Scale Water Monitoring Program for Pesticides (NWMPP)
The Pest Management Regulatory Agency's (PMRA's) anticipated water monitoring program that will aim to generate data for a broad suite of pesticides from a national-scale network of sites. The program would increase the availability and use of real-world data to strengthen pesticide regulatory decisions for the protection of human health and the environment.
Nematicide
Pesticide used to control nematodes.
No observed adverse effects concentration (NOAEC)
Concentration of test substance or material at which there are no statistically or biologically significant increases in the frequency or severity of adverse effects between the exposed organisms or population and the appropriate control.
No observed effect concentration (NOEC)
Highest tested concentration of a substance or material for which there is no statistical difference of effect when compared to the control group.
No observed effect level (NOEL)
Exposure level to a substance or material at which there is no statistical difference of effect when compared to the control group.
Non-detect
Data generated from analysis that identifies a pesticide concentration that falls below the detection limit of the analytical procedure.
Non-target analytical method
Analytical method that aims to detect all pesticides and/or transformation products in a sample without pre-existing knowledge of which may be present. Non-target methods are useful in identifying which pesticide and/or transformation product to target and quantify using targeted methods.
Non-target organism
Any organism that is not intentionally targeted for control by a pesticide.
Non-vascular plant Aquatic Life Reference Value (ALRV)
An estimate of the concentrations of a pesticide below which non-vascular plants (algae) are unlikely to experience adverse effects.
Passive sampling
Environmental monitoring technique that uses either a man-made device or biological organism, to accumulate chemicals from the environment over time. Passive samplers are deployed in water for pre-defined periods of time and accumulate chemicals on sample media based on contaminants that freely flow past the sampling device during the deployment time.
Pest
  1. An animal, a plant or other organism that is injurious, noxious, or troublesome, whether directly or indirectly.
  2. An injurious, noxious or troublesome condition or organic function of an animal, a plant or other organism.
Pest control product (i.e., Pesticide)
A product, an organism or a substance, including a product, an organism or a substance derived through biotechnology, that consists of its active ingredient, formulants and contaminants, and that is manufactured, represented, distributed or used as a means for directly or indirectly controlling, destroying, attracting or repelling a pest or for mitigating or preventing its injurious, noxious or troublesome effects; an active ingredient or any other thing that is prescribed to be a pest control product.
Pest Control Products Act (PCPA)
A Canadian legislation (law) that governs the registration and application of pesticides. This legislation governs the work that is being done under the Pest Management Regulatory Agency.
Pest Management Regulatory Agency (PMRA)
The branch of Health Canada responsible for pesticide regulation in Canada that makes timely, science-based decisions to support the safe and sustainable use of effective pesticide products across the country.
Pesticide mitigation measure
Action taken in order to prevent, reduce or control adverse human health and/or environmental effects of pesticides.
Pesticide mobility
Movement of a pesticide based on its attachment to solids in water, water solubility, and evaporation potential. Highly mobile pesticides are more likely to reach groundwater or runoff into surface waters.
Pesticide modelling
Mathematical calculations that use different types of scientific data in order to estimate the potential exposure concentrations in water for human health and non-target organisms.
Pesticide re-evaluation
The Pest Control Products Act requires the PMRA to initiate re-evaluations of each registered pesticide within 15 years of its initial registration or the most recent major decision affecting the registration. As science continues to evolve, new information, methodologies and approaches that become available over time may affect a previously made regulatory decision. For this reason, PMRA re-evaluates registered pesticides, every 15 years or sooner, to determine whether the use of these products continues to be acceptable according to current standards.
Pesticide special review
Post-registration process under the Pest Control Products Act initiated when there are reasonable grounds to believe that health or environmental risks of a product, or its value, are unacceptable, or when an Organisation for Economic Co-operation and Development member country prohibits all uses of an active ingredient for health or environmental reasons.
Pilot program
A small-scale, short-term study to help learn how a large-scale program might work.
Plant growth regulator
A pest control product that changes the growth pattern of a plant but does not kill the plant.
Quality assurance (QA)
An integrated system of activities involving planning, quality control, quality assessment, reporting and quality improvement to ensure that a product or service meets defined standards of quality with a stated level of confidence.
Quality control (QC)
The overall system that includes operational techniques and activities that measure the attributes and performance of a process, item or service against defined standards to verify that they meet the stated quality requirements established by the customer.
Riparian area/zone
The area between a defined aquatic and terrestrial habitat that may support both aquatic and terrestrial species. They act as important natural biofilters, protecting aquatic environments from sedimentation, surface runoff and erosion. In addition, they supply food and shelter to many aquatic and terrestrial species.
River
A natural flow of water that usually follows a permanent path. Rivers are typically of considerable volume and larger than a brook or creek.
Runoff
  1. That part of the precipitation, snow melt, or irrigation water that appears in uncontrolled surface streams, rivers, drains or sewers. Runoff may be classified according to speed of appearance after rainfall or melting snow as direct runoff or base runoff, and according to source as surface runoff, storm interflow, or groundwater runoff.
  2. The total discharge described in (1), above, during a specified period of time.
Sample detection limit (SDL)
The lowest amount reported by the laboratory for the specific analysis of the reported measurement. Sample detections above method detection limits may indicate dilution, matrix interference or other issues with the specific analysis.
Seasonal wave [seawave] and adjustment for streamflow [Q] model (SEAWAVE-Q)
Model developed by the United States Geological Survey for analyzing trends in chemical concentrations in streams with a seasonal wave (seawave), adjustment for streamflow (Q) and other ancillary variables.
Sediment
Particles that settle to the bottom of water bodies over time, building up the sedimentary compartment of the aquatic ecosystem.
Spray drift
The wind-induced movement of spray particles (droplets) away from the spray swath during application. This definition does not include vapour drift or other mechanisms of off-target deposition such as runoff. See additional information on PMRA's drift migration.
Stream
A general term for a small- to medium-sized body of flowing water that follows a natural water course and contains water at least part of the year. In hydrology, it is generally applied to the water flowing in a natural channel as distinct from a canal.
Surface water
Water that is on the Earth's surface, such as in a stream, river, lake or reservoir.
Suspended particle
Solid fragment that remains suspended in water and acts as colloid. It can consist of clay, debris from plants, animals and biofilms.
Synergist
Any substance or other agent that produces a combined effect greater than the sum of the separate effects. Synergists work to enhance the action of a pesticide.
Target analytical method
Analytical method that intentionally targets a specific pre-determined pesticide and/or transformation product for analysis in a water sample.
Target organism
Any organism that is intentionally targeted for control by a given pesticide.
Technical Working Group (TWG)
Representatives from federal, provincial, and territorial governments, academia, growers, non-governmental organizations, and pesticide manufacturers engaged to inform development of a framework for a National-Scale Water Monitoring Program for Pesticides.
Toxicity
Measurement of the dosage required of a specific substance to affect a living organism. The measurement can be used quantitatively as well as qualitatively to describe the ability of a substance to cause adverse effects.
Trace (T)
A marker (or "flag") on laboratory data that applies to a measurement value (for example, concentration) which falls between a reference range. For water monitoring, Trace refers to concentrations that are greater than the method detection limit (MDL) but less than the level of quantification (LOQ).
Transformation product
A molecule formed from a parent compound (for example, pesticide active ingredient) as a result of metabolism, chemical reactions or environmental processes.
Uncertainty factor (UF)
Consistent with other regulatory authorities, the PMRA applies factors to account for various sources of uncertainty and variability (for example, differences in species sensitivity) within a toxicology database.
United States Environment Protection Agency – Aquatic Life Benchmarks (USEPA ALBs)
Reference concentrations of pesticides in water that are based on available toxicity values from reviewed scientific studies in order to estimate risk to freshwater organisms from exposure to pesticides and their transformation products. See Aquatic Life Benchmarks and Ecological Risk Assessments for Registered Pesticides (US EPA).
Vascular plant Aquatic Life Reference Value (ALRV)
An estimate of the concentrations of a pesticide below which vascular plants (for example, duckweed) are unlikely to experience adverse effects.
Vegetative filter strip (VFS)
Permanently vegetated strip of land located between an agricultural field (cropland) and downslope surface waters (for example, lakes, rivers, potholes) in order to reduce the amount of pesticides entering surface waters from runoff by slowing water and filtering out pesticides carried with the runoff.
Watershed
The land area that drains water to a particular stream, river or lake. It is a land feature that can be identified by tracing a line along the highest elevations between two areas on a map, often a ridge. Large watersheds can contain thousands of smaller watersheds.
Wetland
A distinct ecosystem that is naturally flooded or saturated by water, either permanently or seasonally. There are many classes of wetlands depending on the environment in which they are located, but generally include swamps, marshes and bogs.

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