acute effects
	Toxic effects that are caused by a single exposure to the toxin and result in an immediate health crisis.
allergens
	Substances that activate the immune system and cause an allergic response; may not be directly antigenic themselves but may make other materials antigenic.
antigens
	Substances that stimulate the production of, and react with, specific antibodies.
asphyxiants
	Chemicals that exclude oxygen or actively interfere with oxygen uptake and distribution; includes inert chemicals, such as nitrogen gas or halothane, that can displace oxygen and fill enclosed spaces.
bioaccumulation
	The selective absorption and concentration of molecules by cells.
biomagnification
	Increase in concentration of certain stable chemicals (for example, heavy metals or fat-soluble pesticides) in successively higher trophic levels of a food chain or web.
cancer
	Invasive, out-of-control cell growth that results in malignant tumors.
carcinogens
	Substances that cause cancer.
chronic effects
	Long-lasting results of exposure to a toxin; can be a permanent change caused by a single, acute exposure or a continuous, low-level exposure.
disease
	A deleterious change in the body's condition in response to destabilizing factors, such as nutrition, chemicals, or biological agents.
fetal alcohol syndrome
	A tragic set of permanent physical and mental and behavioral birth defects that result when mothers drink alcohol during pregnancy.
hazardous
	Describes chemicals that are dangerous, including flammables, explosives, irritants, sensitizers, acids, and caustics; may be relatively harmless in diluted concentrations.
health
	A state of physical and emotional well-being; the absence of disease or ailment.
irritants
	Corrosives (strong acids), caustics (alkaline reagents), and other substances that damage biological tissues on contact.
LD50
	A chemical dose lethal to 50 percent of a test population.
morbidity
	Illness or disease.
mutagens
	Agents, such as chemicals or radiation, that damage or alter genetic material (DNA) in cells.
neurotoxins
	Toxic substances, such as lead or mercury, that specifically poison nerve cells.
respiratory fibrotic agents
	Special class of irritants, including chemical reagents and particulate materials, that damages the lungs, causing scar tissue formation that lowers respiratory capacity.
risk
	Probability that something undesirable will happen as a consequence of exposure to a hazard.
stress
	Physical, chemical, or emotional factors that place a strain on an animal. Plants also experience physiological stress under adverse environmental conditions.
teratogens
	Chemicals or other factors that specifically cause abnormalities during embryonic growth and development.
toxins
	Poisonous chemicals that react with specific cellular components to kill cells or to alter growth or development in undesirable ways; often harmful, even in dilute concentrations.
trauma
	Injury caused by accident or violence.

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