Editing Lethal dose (section)

==== Estimation using model organisms ====
LD values for humans are best estimated by extrapolating results from human [[cell culture]]s. One form of measuring LD is to use [[model organism]]s, particularly animals like mice or rats, converting to dosage per kilogram of biomass, and extrapolating to human norms. The degree of error from animal-extrapolated LD values is large. The biology of test animals differs in important aspects to that of humans. For instance, mouse tissue is approximately fifty times less responsive than human tissue to the venom of the [[Sydney funnel-web spider]]{{Citation needed|date=April 2018}}. The [[square–cube law]] also complicates the scaling relationships involved. Researchers are shifting away from animal-based LD measurements in some instances. The U.S. Food and Drug Administration has begun to approve more non-animal methods in response to animal welfare concerns.<ref>{{Cite web
 |title       = Vision and Roadmap for the 21st Century
 |publisher   = [[National Toxicology Program]]
 |url         = http://ntp.niehs.nih.gov/go/vision
 |access-date  = 2011-10-29
 |url-status     = live
 |archive-url  = https://web.archive.org/web/20081012173524/http://ntp.niehs.nih.gov/go/vision
 |archive-date = 2008-10-12
}}</ref>