What does Loec mean?
Lowest Observed Effect Concentration
LOEC (Lowest Observed Effect Concentration) is the lowest concentration where an effect has been observed in chronic ecotoxicity studies.
What is an example of chronic toxicity?
Chronic toxicity is generally thought of as frequent exposures where effects may be delayed (even for years) and are generally irreversible. Chronic toxicity can also result in acute exposures, with long term chronic effects. An example of chronic toxicity relates to cigarette smoking and lung cancer.
What causes chronic toxicity?
Chronic toxicity is caused by repeated exposure to a harmful substance for part of the life-span of an animal, for a major portion of its life-span, or for all of its life-span. Repeat dose toxicity studies are usually conducted in animals with the main aim of defining a No Observed Adverse Effect Level (NOAEL).
What is chronic and acute toxicity?
Acute toxicity is distinguished from chronic toxicity, which describes the adverse health effects from repeated exposures, often at lower levels, to a substance over a longer time period (months or years). It is widely considered unethical to use humans as test subjects for acute (or chronic) toxicity research.
What is MATC toxicology?
The maximum acceptable toxicant concentration (MATC) is a value that is calculated through aquatic toxicity tests to help set water quality regulations for the protection of aquatic life. Regulatory guidelines give two acceptable concentrations of pollutants to protect against effects: chronic or acute.
What causes acute toxicity?
It is caused by exposure to a large dose of a weak toxin or a small dose of a potent (powerful) toxin. This can happen once or numerous times over a short period of time.
What is acute toxicity estimate?
The acute toxicity estimate (ATE) of ingredients is considered as follows: (a) Include ingredients with a known acute toxicity, which fall into any of the acute toxicity categories, or have an oral or dermal LD50 greater than 2000 but less than or equal to 5000 mg/kg body weight (or the equivalent dose for inhalation); …
What is Noael value?
No-observed-adverse-effect level (NOAEL) Greatest concentration or amount of a substance, found by experiment or observation, which causes no detectable adverse alteration of morphology, functional capacity, growth, development or life span of the target organism under defined conditions of exposure.