Why Choose Alternative Cancer Treatments (23)

Better Science: Alternatives to Animal Research (Part 2)

By John McArdle, PhD., Science Advisor New England Anti-Vivisection Society (NEAVS)

contd. from part 1

Skin Toxicity

There are four basic aspects of skin toxicity that are routinely tested: corrosivity, irritation, sensitization and absorption. Skin corrosivity can be easily measured using in vitro systems such as EPISKIN (a three-dimensional human skin model) and EpiDerm (a reconstructed human skin model) – both of which measure cell viability as an endpoint and have been accepted for regulatory purposes in the European Union and by the OECD. In addition, a non-cellular test, Corrositex, is approved in the EU and the United States, but only for acids, bases and their derivatives. Corrositex utilizes a specialized collagen matrix membrane. There is no longer any justification to do animal testing for this endpoint, especially if the in vitro methods are combined with a tiered approach involving such physical parameters as pH.

Skin irritation potential is currently measured using the classic Draize skin test, the lesser-known cousin of its ocular counterpart. Several promising in vitro tests are currently subject to validation programs. These include the EPISKIN and EpiDerm systems, as well as Prediskin (a human skin culture derived from plastic surgery discards) and a variety of sophisticated QSAR models – one of which had a sensitivity of 85% and specificity of 92%. Animal-based tests for this same endpoint should be eliminated in the very near future with an in vitro replacement used immediately for prescreens and priority setting.

Skin sensitization assays are designed to identify a substance’s potential to produce contact dermatitis. Increased responses associated with this endpoint have helped to create new or reapply existing replacement alternatives. Several computer techniques (DEREK, TOPKAT and CASE) include this endpoint.

L’Oreal is developing a human reconstituted epidermis, multi-cell culture model that includes such unique components as melanocytes, keratinocytes and Langerhans cells. MatTek Corporation is actively working on an in vitro replacement for the Murine Local Lymph Node Assay (LLNA), a reduction alternative currently accepted in the EU, United States and by the OECD. Complete replacement of in vivo skin sensitization tests is a realistic short-term expectation.

Percutaneous absorption can be measured using any one of the currently available in vitro reconstituted human skin equivalents since studies show that such methods provide data predictive of human and animal exposure to test substances. In vitro replacements for this endpoint have already been accepted by the OECD.

Genotoxicity / Mutagenicity (changes to genes) and Carcinogenicity (cancer-causing)

It is now widely accepted by regulatory officials and toxicologists that screening for mutagenic potential can be done via in vitro methods such as the Bacterial Reverse Mutation Test; In Vitro Cell Line Mutation Test, or the In Vitro Chromosomal Aberation Test. There are also several SAR, QSAR and Expert Systems available for this endpoint.

The only potential problem with these assays is the existence of mechanisms that produce non-genotoxic carcinogenesis. New in vitro tests based on Syrian Hamster Embryo (SHE) cell lines may address this concern. However, some toxicologists question the significance of such carcinogens to human risk assessment since their activity profiles are often only identified in mice.

Toxicokinetics / Biokinetics -- ADME

Actual systemic toxicity depends on several variables -- external dose; rate of exposure; absorption, distribution, metabolism and excretion (ADME); and the intrinsic characteristics of the test material. All of these can be identified and modeled using computer and in vitro approaches. Studies focusing on ADME are now human-based, mechanistic protocols that provide both predictive and computerized models. Although classical in vivo toxicity tests are based on dose/response relationships for entire animals, a more realistic approach might focus on concentration/response curves at the actual toxic target within the recipient’s body.

In vitro methods are especially useful for such studies on the biological activity and mechanisms of toxic response of chemicals. Programs such as MEIC have provided evidence of the value and utility of this approach.

Perhaps most significantly, the creation of toxicokinetic-derived QSAR programs will allow toxic exposure from one test or set of tests to be used to predict the response for other types of tests. This would eliminate the need for the latter and replace the animals used with simple abstinence. As a specific example, the Environmental Protection Agency (EPA) announced on July 14, 2003, that they had conducted a review to determine if chemical companies could use physiologically-based pharmacokinetic computer models to extrapolate data from previous oral toxicity studies to predict potential hazardous consequences of inhalation exposure to the same substance. The EPA endorsed this approach to both reduce the number of costly tests required and to eliminate some current uses of animals. As mechanistic data, in vitro methods, computer simulation and DNA-chip technology continues to improve and intertwine, the justifications offered to defend continued in vivo testing requirements will become more and more tenuous.

Pyrogen Testing

This test is designed to identify potential bacterial contamination of injectable products (originally), implants, medical devices, dialysis machines, cellular therapies, recombinant proteins and IV products. Injectable drugs have been around for more than 100 years. Sixty years ago the rabbit pyrogen test (involving injection of test materials to check for reactions to contamination) was developed and subsequently millions of rabbits died.

Twenty-five years ago the LAL (Limulus amebocyte lysate) alternative was developed based on the coagulation response of horseshoe crab blood when exposed to bacterial toxins. In theory blood is collected from the crabs, who are then released. In practice, poor technique and carelessness lead to a high percentage of crab fatalities.

To avoid killing the crabs and limitations of the LAL test, as well as the need for replacing the 400,000 rabbits still used worldwide, researchers in Europe developed a new pyrogen test based on human isolated blood cells, cell lines and whole blood incubation to detect the presence of fever reaction products – a direct measure of pyrogen contamination that would affect human patients. This approach can also identify both immunostimulants and immunosuppressants.

Phototoxicity

Although it took seven years to complete the validation/approval/adoption process, there now is an in vitro replacement alternative to identify phototoxic (i.e., drugs and chemicals become toxic when human recipients are exposed to sunlight) potential. The 3T3 Neutral Red Uptake Phototoxicity Test (3T3 NRU PT) utilizes a mouse-derived cell line which measures the degree of cellular damage (cytotoxicity) of the cultures and toxicants when tested in the presence and absence of non-cytotoxic exposure to UVA light.

Additional validation tests are currently being conducted on other in vitro methods (e.g., EpiDerm PT) to provide additional phototoxicity alternatives.

These in vitro methods are accepted by both the OECD and the European Union testing authorities. There is no further justification for the continued use of in vivo tests for this toxic endpoint.

Embryotoxicity / Teratogenicity

There are currently more than a dozen in vitro methods representing various aspects of the reproductive process. The use of immortalized mammalian cell lines, especially embryonic (not derived from therapeutic abortions) stem cells are being used to create in vitro assays for teratogenicity that are directly predictive of human toxic risks. Using rodents for such studies is especially inappropriate due to the major physiological, biochemical and structural differences between human and rodent placentas.

The Embryonic Stem Cell Test (EST) has been validated by the EuropeanCenter for the Validation of Alternative Methods (ECVAM) and accepted in the European Union for the identification of embryotoxicants. Of the currently available alternatives, it is the only one suitable for high throughput screening and avoids killing large numbers of pregnant animals. It also identifies three unique endpoints representing the principal reproductive toxicological mechanisms.

Endocrine Disruptors

This represents a newly hypothesized class of potential toxic effects on human and wildlife reproductive systems for which there were no existing animal-based tests. Although there is evidence that humans may be unaffected by endocrine disruptors, there is also evidence of negative impacts on other species (especially wildlife). Current proposals for in vivo-based testing protocols share a set of serious problems including:

  • lack of reproducibility
  • insufficient or no validations
  • inability to apply standard validation requirements
  • questionable relevance of the data

For these reasons multiple in vitro screens and QSAR computer models are being developed based on mechanistic endpoints that can only be examined using such alternatives. Unlike most existing in vivo tests, because this area of toxic concern is entirely new, it may be possible to create an alternatives-focused, tier-testing strategy that will “do it right” the first time.

Metabolic Toxicity

Some chemicals and drugs are essentially nontoxic but become hazardous once ingested and metabolized by the body. For this reason, information from in vitro systems utilizing human cell lines, genetically engineered human cells and subcellular components as well as several computer-based systems (METEOR, Hazard Expert, Metabol Expert, COMPACT) are being utilized to detect metabolism-mediated toxicity.

Because of the enormous species differences in metabolic parameters (especially between humans and rodents -- the animals most frequently used for such tests), it is critical that such studies utilize human-based in vitro techniques and human data for computer simulation. This is one area of toxicology for which animal models are widely acknowledged by toxicologists to be inappropriate.

Work is currently underway to create a simple microchip that will provide all of the necessary metabolic information simultaneously and in a human-specific context.

Nephro (Kidney) Toxicity

For many years primary cultures of kidney cells have been powerful tools to study renal function and toxicity. A number of in vitro toxicity endpoints are currently being investigated with an emphasis on using immortalized renal epithelial cell lines (e.g., MDCK cells originally derived from dogs). In order to reproduce some of the structural and cellular complexity of the kidneys, new perfusion culture techniques (e.g., EpiFlow) were developed that allow longer-term, simultaneous cultures of two or more cell types. Efforts are also underway to replace all of the animal-derived cell lines and cultures with their respective human counterparts and to identify consistently relevant in vitro toxic endpoints.

Neuro (Brain/Nerve) Toxicity

The routine use of in vitro methods for research and testing models dates back more than twenty years. Long-term cultures of neural and support cells are currently in use by industry to screen for toxic effects of pharmaceuticals, agricultural chemicals and other compounds. In addition, a large number of in vitro systems are being developed as toxicity screens and indicators of multiple toxicity endpoints. These include neuronal cell lines, genetically engineered cells and reaggregating brain cell cultures (which reproduce some of the in vivo complexity of the brain). Eventually a tiered testing (multiple levels of pass/fail testing) strategy, incorporating several of these in vitro methods should be sufficient to identify neurotoxic hazards. There is also evidence that not all potential endpoints need to be examined to adequately predict substances of concern.

Toxicogenomics

If toxicology is to eventually evolve from its primitive beginning in quantifying the mass poisoning of various species of animals, the final high-tech destination may be in the field of toxicogenomics and its sister disciplines of proteonomics and metabonomics – all of which integrate the interactions between human genes and toxic substances, proteins and metabolic activities respectively. The ultimate goal of toxicogenomics is a single or series of DNA chips that would provide almost immediate toxicity profiles of all test substances. Such chips can provide vast amounts of data on gene expression in response to specific conditions. A single chip can replace the information derived from 20,000 individual experiments.

There is evidence that of the mind-boggling number of potential gene expression patterns in the human genome (10 30,000), the number with relevance to toxicologic responses is approximately 317. Once the 256 types of human cells are represented, there only remains another 60 sites of potentially relevant responses to toxic exposures. This is a fairly small number for existing microarray technology.

Each microarray includes thousands of tiny pieces of DNA which allow simultaneous examination of overall patterns of gene expression. The goal of toxicogenomics is to determine which of these patterns are associated with each of the classical toxicity endpoints. Once identified, these arrangements could then be used to predict potential toxicity of new substances.

It is already known that human genes respond to the presence of a compound and any damage associated with it. Genes also respond in characteristic patterns to changes in levels of metabolically important compounds and the internal environment of the cells in the body.

Because of its use of specific gene expression information, microarray-based toxicology would involve a more mechanistic approach to hazard identification and characterization – certainly more relevant to humans than anything currently derived from historically crude animal poison experiments.

A recent set of microarray experiments identified a set of twelve diagnostic points that provided 100% predictive accuracy for five different types of toxic substances. It has also been established that gene expression profiles (as on the chips) correlate with results of histopathology, clinical chemistry and known mechanisms of toxicity. Studies are currently underway to apply this technology to the fields of hepatotoxicity (liver), genotoxicity (genes) and nephrotoxicity (kidney).

It is also likely that, once fully developed, toxicogenomics will provide the scientific proof that animal-based toxicity testing has little or no relevance to human risk assessment. Use of such chips will become a standard part of any future validation process for in vitro or in vivo safety tests and animal models intended for use in basic biomedical research. Consider the potential consequences of documenting entirely unrelated gene expression profiles for a human disease and its putative animal model surrogate.

Microarrays, once validated and widely adopted, should change toxicology into a high-throughput, predictive discipline with unique sets of biomarkers (gene expression patterns) for toxic endpoints and classes of toxicants. This technology is also uniquely suited to interact with existing in vitro methods. For all of these reasons, pharmaceutical and chemical manufacturing companies are investing heavily in the field of toxicogenomics and creation of DNA microarray chips. This is the beginning of a new age of drug and chemical evaluation.

Enthusiasm for this new, high-tech approach to toxicology may be premature since the biological relevance of gene expression patterns needs to be established and its predictive abilities validated. Some toxicologists have proposed conducting a limited number of animal toxicity tests in order to create the DNA patterns for the chips.

V. ALTERNATIVES AND BIOLOGICALS

Although often overlooked, the production and testing of biologicals consumes 15% or more of all animals used in United States laboratories specifically and the world in general. For example, a complete batch test for a therapeutic protein can involve 12,000 mice and cost $2.4 million without producing any useful information. Potency tests of such products as vaccines are still routinely based on the principle of protection, i.e., survival or death after exposure, which was first introduced in the 1890s. Many of these tests are exceptionally cruel, involving high levels of pain and distress for a variety of species of rodents, dogs, cats and non-human primates (including chimpanzees). According to 1998 USDA statistics, more than 60% of the animals experiencing unrelieved pain and distress were used for vaccine testing. Essentially all of this work was conducted in industry laboratories.

As a category, biologicals include antibodies, blood products, bioactive compounds (e.g., cytokines), hormones, immunosera products, recombinant-DNA proteins and vaccines. Nearly all of these are produced under mandated quality, potency and efficacy controls.

Abandonment of the erroneous concept that functional tests in animals corresponds to the same function in a human, production of biological products in a form which allows easy quantification of characteristics and elimination of excessive duplication of national testing requirements will rapidly advance the development and use of alternative replacements for safety testing of biologicals. For example, introduction of a new vaccine presently might require 32 different in vivo testing protocols instead of a few in vitro alternatives.

The field of biologicals production and testing includes several glaring anachronisms. Target animal safety tests with sample sizes of two are statistically meaningless and could be eliminated immediately. Similarly, the general or abnormal toxicity tests was one of the first animal-based tests developed; is used for a variety of materials; duplicates data produced by more familiar tests; is widely acknowledged to be useless; and was deleted from the European Pharmacopoeia in 1997 with no negative consequences. It could be eliminated worldwide immediately with a similar harmless outcome.

Because some vaccines utilize live pathogens (e.g., oral polio (OPV), MMR, varicella, yellow fever, or are well defined (e.g., influenza), they have always been tested using in vitro methods. Cholera and typhoid vaccines are not tested for potency due to a lack of valid animal models. Neurovirulence tests for OPV, recombinant FSH hormones, tetanus and diptheria vaccines all now have alternative replacements for the previous more traditional animal-based tests.

Vaccines and some biologically active compounds are routinely produced using in vitro methods. Perhaps the most successful example of this is the production of monoclonal antibodies (MAbs), which began as a new in vitro technique; was usurped by a very painful and distressful in vivo method; and can now be done entirely via alternative replacement methods. In fact, there are so many in vitro MAb methods currently available, all producing high quality antibodies at lower costs, that the old in vivo approach is prohibited or severely restricted in many countries including the United States.

Production of polyclonal antibodies continues to rely on injections of test substances (antigens) into various species of animals and subsequent bleeding to retrieve the antibodies. As an interim step, which will also be replaced, such antibodies can be produced in chicken eggs (eliminating the use and bleeding of mammals). Although somewhat technically difficult and in the early stages of development, within a few years it will be possible to use recombinant DNA techniques to produce all antibodies – mono- and polyclonal. This final evolution of technological methods will completely eliminate an entire area of traditional animal usage (millions of animals per year) and at the same time provide a higher quality, less expensive product. This is the promise and reality of the alternatives approach.

VI. ALTERNATIVES AND EDUCATION

Because educational demonstrations and laboratory sessions are characterized by repetitive exposure to existing knowledge, they represent the ideal situation for the application of replacement alternatives. For this reason the “alternatives approach” to education in the biomedical sciences has had its most widespread success in primary, secondary, undergraduate and graduate/professional curricula. There is no longer any valid educational or scientific justification for the continued use of animals to acquire either basic knowledge or practice manual skills. In the 1990s NEAVS’ educational affiliate, The Ethical Science and Education Coalition, published one of the first resources on available alternatives appropriate to middle and high school level life science classes. NEAVS has also been a major funder of From Guinea Pig to Computer Mouse, second edition (2002) – an exhaustive resource of alternatives appropriate for college, university and professional school levels. Compiled and published by the International Network for Humane Education (InterNICHE), it lists more than 500 alternatives and is available in several languages.

For more than a century it has been illegal in the United Kingdom to use animals for such basic educational purposes. When this law was revised in the 1980s (after more than 100 years of successful application to classrooms), only one exception was allowed (microsurgery practice) for which appropriate replacement alternatives are now available. Comparative studies of basic knowledge and professional skills (e.g., veterinary and human surgeons) confirm that individuals trained under the alternatives-focused United Kingdom system are not less qualified than their counterparts exposed to the more animal-based approach still common in the United States. There are no documented disadvantages associated with the exclusive use of humane alternatives. In 1999 NEAVS worked with Tufts University School of Veterinary College to make it the first US vet school to eliminate all terminal labs on all species. The trend in both medical and veterinary schools is rapidly moving toward making all live animal labs either electives or eliminated.

It is now possible for a student to go through primary, secondary and undergraduate education (even with an emphasis in biology) and not need to harm, kill living animals or work on already dead animals.

For more detailed information on issues associated with educational uses of alternatives and animals, please go to the ESEC website.

VII. RESISTANCE TO ALTERNATIVES

Although the “alternatives approach” represents state-of-the-art scientific methods, superior to traditional animal-based approaches, in the United States there remains considerable resistance among many academic researchers, toxicologists and regulatory officials to making the switch to more humane approaches to experimentation, testing and education. Experts in this field have observed:

“Many toxicologists and regulators do not want to question the value of the methods they currently use.” Michael Balls, Ph.D., former Director, ECVAM, 2002

“Regulators appear to be more willing to accept new animal tests which have not been validated than non-animal tests which have.” Michael Balls, Ph.D., former Director, ECVAM, 1998

“Behind all of this there lies a profoundly irrational bias in favor of in vivo tests.” William Russell, Ph.D., founder of modern alternatives movement, 2003

“Extreme views on both sides of the animal research battle have led to a stalemate in which any search for alternatives is too often seen as a concession to animal rightists. As a result, the United States lags far behind Europe in finding and implementing alternatives.” John Rennie, 1997 / Editor, Scientific American

There is also a general consensus that resistance to the identification, development, adoption and promotion of humane alternatives reflects several attitudes and biases, which are not mutually exclusive. These include, but are not limited to:

  • blind acceptance of in vivo methods and animal models
  • lack of support (financial and professional) for development and validation of alternatives and basic toxicological research
  • anachronistic regulatory mandates, tradition and political barriers to acceptance of validated alternatives
  • poor quality of comparative in vivo and relative absence of human data for use in validation studies
  • fears of litigation by liability attorneys and insurance companies who prefer historical in vivo data regardless of its validity
  • psychological factors rooted in ignorance of in vitro methods and general fear of change
  • unrealistic expectations of current in vitro methods and the validation process
  • poorly worded testing mandates and regulatory inertia
  • preference for check-box or six-pack testing programs rather than chemical-specific requirements
  • lobbying by biomedical trade associates and animal suppliers with vested financial interests in the continuation of animal experimentation and testing

All of these barriers are being overcome at an accelerating, but still frustratingly slow pace. The future of animal-based experimentation, testing and education is questionable. As noted by Nobel Prize winner Sir Peter Medawar:

“The use of experimental animals on the present scale is a temporary episode in biological and medical history.”

VIII. CHALLENGES TO ALTERNATIVES

In addition to the resistance described above, more direct threats to the adoption of alternatives and promotion of animal-based testing protocols may come from massive new testing programs being proposed by such federal regulatory bodies as the Environmental Protection Agency (EPA).

For the past few years, under pressure from politicians as well as consumer and environmental organizations, the EPA has proposed new testing requirements that will kill millions of animals, tailored to:

  • High Production Volume Chemicals (HPV)
  • Endocrine Disruptors (ED)
  • Children’s Health Initiative (CHI)

Nearly identical programs have also been proposed for the European Union (REACH) and internationally (OECD). In all cases the respective regulatory agencies have used the new testing mandates to promote existing or create new animal-based testing procedures – usually without the rigorous levels of validation and proof of principle still required for in vitro replacement alternatives. If needed, the new testing requirements could be used as incentives to finally create an alternatives-based, humane approach to assessing human health and safety. The fact that tens of thousands of chemicals have been and continue to be produced without adequate safety/risk assessments is a clear indication of the historical failures of in vivo approaches and not a reason to massively expand such inappropriate approaches to testing.

IX. CRUELTY-FREE IN VITRO

In vitro alternatives are generally accepted as more humane replacements for animal-based procedures. However, it is not widely known that in vitro techniques may not necessarily be cruelty-free. Cells used in such cultures may be directly derived from non-human animals. To be cruelty-free, human or existing animal cell lines should be the source for all cells, tissues and organs used in research and testing.

It is also common for cell cultures (and most organ and tissue cultures) to be created with primary cells (cells derived from recently killed animals) rather than immortalized cells. Thus every time a culture is started, one or more animals may be killed. To be cruelty-free, all in vitro techniques should utilize only immortalized animal cells or primary human cells, tissues and organs.

Even if the cells are immortalized or of human origin, there remains the concerns created by supplements added to the culture media to promote the growth and survival of the cells, tissues and/or organs. There are a variety of bioactive compounds used as supplements, with the most serious problems being associated with the production and use of fetal calf serum (FCS) or serum from other animals. FCS production involves conditions associated with high levels of cruelty, pain and distress including, but not limited to, puncturing the heart and draining all of the blood from unanesthetized animals. To be cruelty-free, in vitro methods must utilize cells, tissues and organs specifically adapted to serum-free culture media or the use of supplements derived from in vitro production techniques or human blood serum. Although readily available, such alternative sources of cell and tissue growth supplements are often ignored due to reliance on more familiar or traditional animal-based production methods.

X. WHAT NEEDS TO BE DONE

Academia – Government – Industry – Consumers

Simple procedural changes by regulatory organizations and industry that do not require any new validated tests could drastically and immediately reduce the number of animals used in safety testing as well as promote greater reliance on humane alternatives. These would include the following:

  • Minimize testing done for notification purposes (e.g., new batches of approved substances).
  • Place an emphasis on alternatives-focused, step-wise or tier-testing rather than simplistic adherence to check-box or six-pack protocols.
  • Mandate the inclusion of structure-activity relationships, in vitro methods and mathematical models whenever available.
  • Prohibit tests that are irrelevant to the use of the product.
  • Switch the scientific basis of toxicity testing from correlative to mechanistically-based methods.
  • Facilitate dialogue between the scientific, toxicological and industry communities, with mandatory requirements for data sharing.
  • Promote greater international harmonization of both testing requirements and data acceptance. There is no need for each country to repeat the validation and regulatory decisions of another.
  • Fully analyze public and private databases for information on existing chemicals to enhance computerized testing programs and to determine if significant “gaps” actually exist.
  • Support the creation and enforcement of legal requirements for immediate regulatory acceptance and academic/industry use of validated alternatives.
  • NIH and other research support agencies and organizations should give higher approval review scores to protocols based on the development and/or use of alternative methods. Regulatory agencies should proactively support use and submission of in vitro versus in vivo data.
  • The United States needs effective inter-agency dialogue and coordination to centralize and promote alternative method development and validation, regardless of individual agency regulatory mandates.
  • Human tissues are still not available in sufficient amounts to meet the needs of basic researchers and toxicity testing. A nation-wide system of donor promotion and storage facilities is needed.

There is still a need for more collaboration between and financial support from academia, industry and regulatory agencies to proactively support the identification, fast-track development, validation, acceptance and use of new alternative methods. This would include increased funding for high quality validation studies and provisions of adequate resources and specialized laboratories to design and manage those projects. Initially there should be priority funding for key target areas such as HPV, ED and basic research involving pain and distress to the animals.

XI. PERSONAL CHOICES

Individuals, groups and organizations can choose to not directly participate or support the continued use of animal-based safety testing protocols. Instead they can:

  • Promote and live a “green” lifestyle and workplace, keeping the use of chemicals to a minimum; avoiding the use of “new” or “improved” products and purchase only cruelty-free household and personal care and business products.
  • If they are members of an environmental organization that promotes increased testing of new or existing chemicals, individuals can suggest that such activities only involve the use of alternatives and a prohibition of animal-based methods.
  • Do not contribute to health charities that still rely on outdated, cruel and inefficient animal research.
  • Support NEAVS’ efforts to create a more humane and safer world for animals and humans by promoting the development, validation, adoption and acceptance of replacement alternatives for all current uses of animals in basic biomedical research, product development and safety testing and educational demonstrations.

Compare What you can do to help.

In addition to what has been accomplished during the past twenty years, given sufficient motivation, financial support and official endorsement, there is no compelling reason why the vast majority of animal-based safety tests could not be replaced within the next four to five years. These would include:

  • eye irritation
  • skin sensitization
  • skin penetration
  • nephrotoxicity (kidney)
  • hepatotoxicity (liver)
  • neurotoxicity (brain/nerves)
  • endocrine disruptors
  • the blood-brain barrier
  • acute systemic toxicity
  • chronic systemic toxicity
  • chemical carcinogenesis

As noted more than two decades ago, the development and use of replacement alternatives is only limited by the imagination of the investigators involved, financial support and the level of personal and professional cooperation and commitment of industry, politicians, administrators, basic researchers, applied scientists, animal advocates and regulatory officials in support of achieving the goal of better and more compassionate science.

There is no doubt that replacement alternatives are the future of biomedical research, testing and education and that this can happen sooner rather than later. Your support for NEAVS and its programs will help hasten this inevitable and necessary transition away from animal-based experimentation, testing and teaching and toward science and science education governed by progressive scientific thought and compassionate ethics.

About the New England Anti-Vivisection Society (NEAVS)

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