The Draize test is an acute

toxicity test Toxicology testing, also known as safety assessment, or toxicity testing, is the process of determining the degree to which a substance of interest negatively impacts the normal biological functions of an organism, given a certain exposure durati ...

devised in 1944 by

Food and Drug Administration The United States Food and Drug Administration (FDA or US FDA) is a List of United States federal agencies, federal agency of the United States Department of Health and Human Services, Department of Health and Human Services. The FDA is respon ...

(FDA)

toxicologists Toxicology is a scientific discipline, overlapping with biology, chemistry, pharmacology, and medicine, that involves the study of the adverse effects of chemical substances on living organisms and the practice of diagnosing and treating expos ...

John H. Draize and Jacob M. Spines. Initially used for testing cosmetics, the procedure involves applying 0.5 mL or 0.5 g of a test substance to the eye or skin of a restrained, conscious animal, and then leaving it for set amount of time before rinsing it out and recording its effects. The animals are observed for up to 14 days for signs of

erythema Erythema (from the Greek , meaning red) is redness of the skin or mucous membranes, caused by hyperemia (increased blood flow) in superficial capillaries. It occurs with any skin injury, infection, or inflammation. Examples of erythema not assoc ...

and

edema Edema, also spelled oedema, and also known as fluid retention, dropsy, hydropsy and swelling, is the build-up of fluid in the body's Tissue (biology), tissue. Most commonly, the legs or arms are affected. Symptoms may include skin which feels t ...

in the skin test, and redness, swelling, discharge, ulceration, hemorrhaging, cloudiness, or blindness in the tested eye. The test subject is commonly an

albino Albinism is the congenital absence of melanin in an animal or plant resulting in white hair, feathers, scales and skin and pink or blue eyes. Individuals with the condition are referred to as albino. Varied use and interpretation of the term ...

rabbit, though other species are used too, including dogs. The animals are euthanized after testing if the test renders irreversible damage to the eye or skin. Animals may be re-used for testing purposes if the product tested causes no permanent damage. Animals are typically reused after a "wash out" period during which all traces of the tested product are allowed to disperse from the test site.Animals in Product Testing
, National Anti-Vivisection Society, retrieved 29 June 2009. The tests are controversial. They are viewed as cruel as well as unscientific by critics because of the differences between rabbit and human eyes, and the subjective nature of the visual evaluations. The FDA supports the test, stating that "to date, no single test, or battery of tests, has been accepted by the

scientific community The scientific community is a diverse network of interacting scientists. It includes many " sub-communities" working on particular scientific fields, and within particular institutions; interdisciplinary and cross-institutional activities are als ...

as a replacement or... the Draize test". Because of its controversial nature, the use of the Draize test in the U.S. and Europe has declined in recent years and is sometimes modified so that

anaesthetic An anesthetic (American English) or anaesthetic (British English; see spelling differences) is a drug used to induce anesthesia ⁠— ⁠in other words, to result in a temporary loss of sensation or awareness. They may be divided into two ...

s are administered and lower doses of the test substances used. Chemicals already shown to have adverse effects ''

in vitro ''In vitro'' (meaning in glass, or ''in the glass'') studies are performed with microorganisms, cells, or biological molecules outside their normal biological context. Colloquially called "test-tube experiments", these studies in biology an ...

'' are not currently used in a Draize test, thereby reducing the number and severity of tests that are carried out.

Background

John Henry Draize (1900–1992) obtained a BSc in chemistry then a PhD in pharmacology, studying

hyperthyroidism Hyperthyroidism is the condition that occurs due to excessive production of thyroid hormones by the thyroid gland. Thyrotoxicosis is the condition that occurs due to excessive thyroid hormone of any cause and therefore includes hyperthyroidism ...

. He then joined the

University of Wyoming The University of Wyoming (UW) is a public land-grant research university in Laramie, Wyoming. It was founded in March 1886, four years before the territory was admitted as the 44th state, and opened in September 1887. The University of Wyoming ...

and investigated plants poisonous to cattle, other livestock, and people. The U.S. Army recruited Draize in 1935 to investigate the effects of

mustard gas Mustard gas or sulfur mustard is a chemical compound belonging to a family of cytotoxic and blister agents known as mustard agents. The name ''mustard gas'' is technically incorrect: the substance, when dispersed, is often not actually a gas, b ...

and other chemical agents. In 1938, after a number of reports of

coal tar Coal tar is a thick dark liquid which is a by-product of the production of coke and coal gas from coal. It is a type of creosote. It has both medical and industrial uses. Medicinally it is a topical medication applied to skin to treat psoriasi ...

mascara Mascara is a cosmetic commonly used to enhance the upper and lower eyelashes. It is used to darken, thicken, lengthen, and/or define the eyelashes. Normally in one of three forms—liquid, powder, or cream—the modern mascara product has vario ...

leading to blindness, the U.S. Congress passed the Federal

Food, Drug, and Cosmetic Act The United States Federal Food, Drug, and Cosmetic Act (abbreviated as FFDCA, FDCA, or FD&C) is a set of laws passed by the United States Congress in 1938 giving authority to the U.S. Food and Drug Administration (FDA) to oversee the safety of f ...

, placing

cosmetics Cosmetics are constituted mixtures of chemical compounds derived from either natural sources, or synthetically created ones. Cosmetics have various purposes. Those designed for personal care and skin care can be used to cleanse or protect ...

under regulatory control. The following year Draize joined the FDA, and was soon promoted to head of the Dermal and Ocular Toxicity Branch where he was charged with developing methods for testing the side effects of cosmetic products. This work culminated in a report by Draize, his laboratory assistant, Geoffrey Woodard, and division chief, Herbert Calvery, describing how to assess acute, intermediate, and chronic exposure to cosmetics by applying compounds to the skin, penis, and eyes of rabbits. Following this report, the techniques were used by the FDA to evaluate the safety of substances such as

insecticide Insecticides are substances used to kill insects. They include ovicides and larvicides used against insect eggs and larvae, respectively. Insecticides are used in agriculture, medicine, industry and by consumers. Insecticides are claimed to b ...

s and

sunscreen Sunscreen, also known as sunblock or sun cream, is a photoprotective topical product for the skin that mainly absorbs, or to a much lesser extent reflects, some of the sun's ultraviolet (UV) radiation and thus helps protect against sunburn and ...

s and later adopted to screen many other compounds. By Draize's retirement in 1963, and despite never having personally attached his name to any technique, irritancy procedures were commonly known as "the Draize test" To distinguish the target organ, the tests are now often referred to as "the Draize eye test" and "the Draize skin test".

Reliability

In 1971, before the implementation in 1981 of the modern Draize protocol,

Carrol Weil and Robert Scala of

Carnegie Mellon University Carnegie Mellon University (CMU) is a private research university in Pittsburgh, Pennsylvania. One of its predecessors was established in 1900 by Andrew Carnegie as the Carnegie Technical Schools; it became the Carnegie Institute of Technology ...

distributed three test substances for comparative analysis to 24 different university and state laboratories. The laboratories returned significantly different evaluations, from non-irritating to severely irritating, for the same substances. A 2004 study by the U.S. Scientific Advisory Committee on Alternative Toxicological Methods analyzed the modern Draize skin test. They found that tests would: * Misidentify a serious irritant as safe: 0–0.01% * Misidentify a mild irritant as safe: 3.7–5.5% * Misidentify a serious irritant as a mild irritant: 10.3–38.7%

Descriptions of the test

Anti-testing

According to the American

National Anti-Vivisection Society The National Anti-Vivisection Society (NAVS) is an international not-for-profit animal protection group, based in London, working to end animal testing, and focused on the replacement of animals in research with advanced, scientific techniques. S ...

, solutions of products are applied directly into the animals' eyes, which can cause "intense burning, itching and pain". Clips are placed on the rabbits' eyelids to hold them open during the test period, which can last several days, during which time the rabbits are placed in restraining stocks. The chemicals often leave the eyes "ulcerated and bleeding". In the Draize test for skin irritancy, the test substances are applied to skin that is shaved and abraded (several layers of skin are removed with sticky tape), then covered with plastic sheeting.

Pro-testing

According to the British

Research Defence Society The Research Defence Society was a British scientific society and lobby group, founded by Stephen Paget, in 1908, to fight against the anti-vivisectionist "enemies of reason" at the beginning of the 20th century. At the end of 2008, after being a ...

, the Draize eye test is now a "very mild test", in which small amounts of substances are used and are washed out of the eye at the first sign of irritation. In a letter to ''

Nature Nature, in the broadest sense, is the physics, physical world or universe. "Nature" can refer to the phenomenon, phenomena of the physical world, and also to life in general. The study of nature is a large, if not the only, part of science. ...

'', written to refute an article saying that the Draize test had not changed much since the 1940s,

Andrew Huxley Sir Andrew Fielding Huxley (22 November 191730 May 2012) was an English physiologist and biophysicist. He was born into the prominent Huxley family. After leaving Westminster School in central London, he went to Trinity College, Cambridge on ...

wrote: "A substance expected from its chemical nature to be seriously painful must not be tested in this way; the test is permissible only if the substance has already been shown not to cause pain when applied to skin, and ''in vitro'' pre-screening tests are recommended, such as a test on an isolated and perfused eye. Permission to carry out the test on several animals is given only if the test has been performed on a single animal and a period of 24 hours has been allowed for injury to become evident."

Differences between the rabbit eye and the human eyes

Kirk Wilhelmus, professor in the Department of Ophthalmology at

Baylor College of Medicine Baylor College of Medicine (BCM) is a medical school and research center in Houston, Texas, within the Texas Medical Center, the world's largest medical center. BCM is composed of four academic components: the School of Medicine, the Graduate Sc ...

, conducted a comprehensive review of the Draize eye test in 2001. He also reported that differences in anatomy and biochemistry between the rabbit and human eye indicate that testing substances on rabbits might not predict the effects on humans. However, he noted "that eyes of rabbits are generally more susceptible to irritating substances than the eyes of humans" making them a conservative

model A model is an informative representation of an object, person or system. The term originally denoted the Plan_(drawing), plans of a building in late 16th-century English, and derived via French and Italian ultimately from Latin ''modulus'', a mea ...

of the human eye. Wilhelmus concluded "The Draize eye test ... has assuredly prevented harm" to humans, but predicts it will be "supplanted as ''in vitro'' and clinical alternatives emerge for assessing irritancy of the ocular surface".

Alternatives

Industry and regulatory bodies responsible for public health are actively assessing animal-free tests to reduce the requirement for Draize testing. Before 2009 the

Organisation for Economic Co-operation and Development The Organisation for Economic Co-operation and Development (OECD; french: Organisation de coopération et de développement économiques, ''OCDE'') is an intergovernmental organization, intergovernmental organisation with 38 member countries ...

(OECD) had not validated any alternative methods for testing eye or skin irritation potential. However, since 2000 OECD had validated alternative tests for corrosivity, meaning acids, bases and other corrosive substances are no longer required to be Draize tested on animals. The alternative tests include a human skin equivalent model and the transepicutaneous resistance test (TER). In addition, the use of human corneal cell line (HCE-T cells) is also another good alternative method to test eye irritation on potential chemicals. In September 2009 the OECD validated two alternatives to the Draize eye test: the bovine cornea opacity test (BCOP) and isolated chicken eye test (ICE). A 1995 study funded by the

European Commission The European Commission (EC) is the executive of the European Union (EU). It operates as a cabinet government, with 27 members of the Commission (informally known as "Commissioners") headed by a President. It includes an administrative body o ...

and British Home Office evaluated these among nine potential replacements, including the hens' egg

chorioallantoic membrane The Chorioallantoic Membrane (CAM), also known as the chorioallantois, is a highly vascularized membrane found in the eggs of certain amniotes like birds and reptiles. It is formed by the fusion of the mesodermal layers of two extra-embryonic memb ...

(HET-CAM) assay and an epithelial model cultivated from human corneal cells, in comparison with Draize test data. The study found that none of the alternative tests, taken alone, proved to be a reliable replacement for the animal test, however a ''post hoc'' analysis of the data found that in certain combinations of tests, an "excellent performance" was observed. Positive results from some of these tests have been accepted by regulatory bodies, such as the British

Health and Safety Executive The Health and Safety Executive (HSE) is a UK government agency responsible for the encouragement, regulation and enforcement of workplace health, safety and welfare, and for research into occupational risks in Great Britain. It is a non-depar ...

and US

Department of Health and Human Services The United States Department of Health and Human Services (HHS) is a cabinet-level executive branch department of the U.S. federal government created to protect the health of all Americans and providing essential human services. Its motto is " ...

, without testing on live animals, but negative results (no irritation) required further ''in vivo'' testing. Regulatory bodies have therefore begun to adopt a tiered testing strategy for skin and eye irritation, using alternatives to reduce Draize testing of substances with the most severe effects.

Regulations

UK

In Britain, the Home Office publishes guideline for eye irritancy tests, with the aim of reducing suffering to the animals. In its 2006 guidelines, it "strongly encourages" ''in vitro'' screening of all compounds before testing on animals, and mandates the use of validated alternatives when available. It requires that the test solution's "physical and chemical properties are not such that a severe adverse reaction could be predicted"; therefore "known

corrosive A corrosive substance is one that will damage or destroy other substances with which it comes into contact by means of a chemical reaction. Etymology The word ''corrosive'' is derived from the Latin verb ''corrodere'', which means ''to gnaw'', ...

substances or those with a high

oxidation Redox (reduction–oxidation, , ) is a type of chemical reaction in which the oxidation states of substrate change. Oxidation is the loss of electrons or an increase in the oxidation state, while reduction is the gain of electrons or a d ...

or reduction potential must not be tested."Eye Irritation Tests
, UK Home Office, retrieved 29 June 2009. The test design requires that the substance be tested on one rabbit initially, and the effect of the substance on the skin must be ascertained before it can be introduced into the eye. If a rabbit shows signs of "severe pain" or distress it must be immediately killed, the study terminated and the compound may not be tested on other animals. In tests where severe eye irritancy is considered likely, a washout should closely follow testing in the eye of the first rabbit. In the UK, any departure from these guidelines requires prior approval from the Secretary of State.