Lethal Concentration 50 Percent

Term · Environment · MLC-T-ENV-015615

1. Median level concentration, a standard measure of toxicity. It tells how much of a substance is needed to kill half of a group of experimental organisms in a given time. [EPA 2005b]

2. Concentration of a pollutant or effluent at which 50% of the test organisms die; a common measure of acute toxicity. [EPA 2005e]

3. Concentration of a substance in air [typically micrograms per cubic meter (µg/m3)] or water [typically micrograms per liter (µg/l)] that kills 50 percent of a group of exposed organisms. The LC50 is used in the HRS in assessing acute toxicity.

Table 1. Record
Identifier	MLC-T-ENV-015615
Field	Environment
References	Adapted from Thesaurus of Terms Used in Microbial Risk Assessment; 40 CFR Appendix A to Part 300 (CFR 2013)

Record as JSON

{
  "id": "MLC-T-ENV-015615",
  "term": "Lethal Concentration 50 Percent",
  "field": "Environment",
  "definition": "1. Median level concentration, a standard measure of toxicity. It tells how much of a substance is needed to kill half of a group of experimental organisms in a given time. [EPA 2005b]\n\n2. Concentration of a pollutant or effluent at which 50% of the test organisms die; a common measure of acute toxicity. [EPA 2005e]\n\n3. Concentration of a substance in air [typically micrograms per cubic meter (µg/m3)] or water [typically micrograms per liter (µg/l)] that kills 50 percent of a group of exposed organisms. The LC50 is used in the HRS in assessing acute toxicity.",
  "references": [
    "Adapted from Thesaurus of Terms Used in Microbial Risk Assessment",
    "40 CFR Appendix A to Part 300 (CFR 2013)"
  ],
  "url": "https://mlchart.com/terminology/environment/lethal-concentration-50-percent/"
}

Record 15,615 of 30,736 in Environment terminology (MLC-0121). Request the full dataset.