Glossary of Toxicology: Understanding Key Terms in Health Risk Assessment
To understand the quality of our home environment, measure air pollution, or analyze the impact of chemicals on health, a solid grasp of the fundamental concepts of health safety is essential. Laboratory analysis reports and impact assessments are full of technical terms and complex acronyms. This toxicology glossary lists and defines the key concepts related to health effects and regulatory reference thresholds.
The Main Types of Toxicity and Health Effects
Toxicity refers to a chemical substance's ability to cause harmful effects in a living organism. Depending on the nature of the substance, the dose, and the duration of exposure, these effects target different organs or biological functions:
CMR (Carcinogenic, Mutagenic, Reprotoxic)
An acronym for substances that pose the most serious risks to humans.
Carcinogen: a substance capable of causing cancer or increasing its incidence.
Mutagen: an agent that causes genetic mutations that alter DNA, which may or may not be passed on to daughter cells.
Reprotoxic: a compound that impairs reproductive function or capacity in men or women (decreased fertility, impairment of gametes).
Teratogen
A substance that causes birth defects during the development of the embryo or fetus during pregnancy.
Neurotoxic
A toxic substance that alters the structure or function of the central nervous system (brain) or the peripheral nervous system (nerves).
Hepatotoxic
A substance that causes damage or dysfunction in the liver (a key organ in detoxification).
Hematotoxic
A substance that interferes with the production or function of blood cells (red blood cells, white blood cells, platelets).
Nephrotoxic
Toxic, causing damage to the kidneys and impairing renal filtration.
Endocrine disruptor
A substance foreign to the body that interferes with the endocrine system, causing harmful effects on health or on offspring.
Parameters for Assessing Acute and Chronic Toxicity
Experimental toxicity assessment relies on quantitative indicators to determine the intrinsic hazard of a molecule:
LD50 (Lethal Dose 50%)
A single dose of a substance calculated to kill 50% of a test animal population. It is used to assess acute toxicity (the lower the LD50, the more toxic the substance).
NOAEL (No Observed Adverse Effect Level / Dose sans effet observable)
The highest dose of a substance that does not cause any measurable toxic effects in long-term repeated-dose tests.
Reference values, health standards, and regulatory standards
Based on experimental data, public health agencies (such as ANSES) establish reference values designed to protect the general public or workers from chronic exposure:
TRV (Toxicological Reference Value)
A health exposure level established by experts below which the population is not at risk of adverse health effects.
ADI (Acceptable Daily Intake)
The amount of a substance (such as a pesticide or additive) that a person can ingest daily throughout their lifetime without any significant health risk.
MRL (Maximum Residue Limit)
Maximum legal concentration of pesticide residues permitted in or on food and animal feed.
SRV (Statistical Reference Value)
A value derived from national monitoring campaigns that indicates the background level of a pollutant in a given population or environment.
VGAI (Indoor Air Quality Guide Value)
The concentration level of a pollutant in indoor air set by health authorities to prevent health risks in enclosed spaces.
OEL (Occupational Exposure Limit)
The maximum concentration of a chemical agent present in the air within an employee's breathing zone, established to prevent occupational diseases in the workplace.
With this toxicology glossary, you’ll have everything you need to confidently read and interpret your air and dust analysis reports.
