Botox and animal testing 

Rebecca Ram, Lush Prize Science Consultant, looks at the use of animals in testing of botox.

Botox, given its full name Botulinum neurotoxin (also abbreviated to BoNT) is one of the most lethal substances (if not the most lethal) known to humans. It is highly poisonous, even in the tiniest quantities, and was first identified from fatal food poisonings (‘botulism’) after eating rotten meat. 

Cosmetic vs medical use of Botox

Although Botox is used to treat medical conditions, the ever rising and dominant global use of Botox is for cosmetic (or aesthetic) purposes. As it is injected, Botox falls outside of the definition of a ‘cosmetic’ as per EU regulations. This means it also evades the EU ban on animal tests for cosmetics via a major loophole. 

Botox also remains widely prescribed ‘off label’ for cosmetic purposes, which has contributed to the global boom in its use to enhance appearance. Furthermore, wrinkles may often be defined as medical issues to allow Botox use. 

The batch potency (LD50) test in mice

The lethality of Botox and the way it is prepared makes it vulnerable to variability between production batches. Therefore, each batch, regardless of its intended purpose, is tested for potency in mice. For each ‘batch potency’ test (also known as a lethal dose or ‘LD50’ test) the mice are divided into groups and injected abdominally with increasing doses of the toxin. The goal of this cruel and archaic test (the LD50 has been in use since 1927) is to see what dose level causes death as an ‘endpoint’ in 50% of the mice. Many more animals suffer in additional tests each time new Botox preparations are initially produced.

Animals used in toxicity tests for Botox endure immense distress, pain and suffering at its most severe, including (among other symptoms) muscle paralysis, breathing problems and asphyxiation which can last days, until an agonising death. 

Botox testing in Ireland and elsewhere

Ireland is responsible for the most animal testing for Botox in the EU, due to a large manufacturing and testing industry there. 

Although a ‘partial ‘alternative method to using animals has been available since 2011 (developed by Botox makers Allergan), it is only used for certain subtypes of Botox and/or for certain preparations. Also, commercial competitiveness and confidentiality have prevented the test from being used more widely, although use of non-animal methods is increasing. However, animals may still be used instead of the available alternative. Therefore, mice still suffer in Botox tests every day. 

Over 400,000 mice per year were used in Botox testing in the EU in 2019, and official statistics from 2022 show that 59,224 mice were used for batch potency testing in Ireland alone. This is from a total of 92,939 animals used, meaning that batch potency tests represent 64% of animal tests in Ireland. Though numbers have declined, there remains an urgent need to see Botox testing numbers reduced to zero. 

Germany is home to several Botox brand manufacturers (and therefore routine animal testing) and there is significant testing outside Europe by other companies, although the exact scale of animals used is difficult to obtain. 

The science explained

Botox exerts its effects on the ‘neuromuscular junctions’ (NMJ) of cells to block the release of a chemical (acetylcholine) which causes muscle contraction. It therefore disrupts the action of acetylcholine across the NMJ to cause muscle paralysis, which has led to it being used for cosmetic reasons to reduce wrinkles and fine lines. However, the effect is temporary, which is why cosmetic clients very often return for repeat injections. 

Lush Prize nominated research to end animal tests for Botox

Lush Prize has received both past and present nominations for high quality, human-relevant research models and campaigns to end animal suffering for Botox testing, while addressing the need for better science without reliance on outdated and unreliable animal-based methods, which continue to be used primarily due to ‘tick box’ conventions.

 As Botox has a variety of applications (from cosmetics to medical purposes to food contamination and more), these new models offer the potential to replace animals across these applications, to overcome the ethical and scientific limitations of the cruel and outdated lethal dose tests which have been used for decades. 

25 April 2024