Under the Federal Hazardous Substances Act (FHSA), animal testing is not mandatory; it is one possible option that can be used to determine the biological response and appropriate cautionary labeling for a consumer product. The Commission's policy is to find alternatives to animal testing and to reduce the number of animals tested and decrease the pain and suffering associated with testing of household products in animals. As such, the Commission strongly supports the use of scientifically validated alternatives to animal testing and the use of existing information, including expert opinion, prior human experience, and prior animal testing results, in the determination of hazard. CPSC is a member of the Interagency Coordinating Committee on the Validation of Alternative Methods (ICCVAM), and as such, supports the development and use of validated alternative test methods.
The CPSC has proposed to codify its policy on animal testing at 16 CFR § 1500.232 (77 FR 38751). In addition, the CPSC has proposed to amend and update its animal testing regulations to allow alternatives to animal testing, whenever possible, under 16 CFR part 1500 (77 FR 38754). The information on this page is intended to supplement the CPSC's proposed statement of policy on animal testing to help industry determine what tests currently are acceptable and available for meeting the labeling requirements of the FHSA.
Acute Toxicity Testing
Ocular Irritation Testing
Dermal Irritation Testing
Sensitization Testing
Commission Votes and other CPSC Approvals Pertinent to Alternatives to Animal Testing
Acute Toxicity Testing
For each of three exposure routes (oral, dermal, and inhalation), the FHSA distinguishes two levels of acute toxicity, highly toxic and toxic, from substances that are not toxic, and therefore, do not require labeling. These terms are defined in 16 CFR § 1500.3, along with a description of the traditional method for determining the acute toxicity endpoint, the LD50 or the LC50.
- Oral acute toxicity testing
16 CFR § 1500.3(c)(1)(ii)(A) defines highly toxic by the oral exposure route and § 1500.3(c)(2)(i)(A) gives the FHSA definition of toxic by the oral exposure route. These sections also contain guidelines for a traditional acute toxicity test. CPSC staff recommends the revised oral Up-and-Down Procedure (UDP) for determining acute oral toxicity for the purpose of classification and labeling under the FHSA. The UDP was issued by U.S. Environmental Protection Agency's Office of Prevention, Pesticides and Toxic Substances (OPPTS) as OPPTS Harmonized Test Guideline 870.1100. The scientifically validated test guideline is referenced in CPSC staff's 2003 Response (pdf) to ICCVAM on Acute Toxicity Testing.In addition, CPSC staff has determined that in vitro basal cytotoxicity tests are appropriate for determining a starting dose for the oral LD50 test. The test guidelines are referenced in CPSC staff's 2008 Response (pdf) to ICCVAM on the Use of In Vitro Basal Cytotoxicity Test Methods for Estimating Starting Doses for Acute Oral Systemic Toxicity Testing.
- Inhalation acute toxicity testing
16 CFR § 1500.3(c)(1)(ii)(B) defines highly toxic by the inhalation exposure route, and § 1500.3(c)(2)(i)(B) gives the FHSA definition of toxic by the inhalation exposure route. Currently, there are no Commission-approved non-animal methods for inhalation toxicity testing.- Dermal acute toxicity testing
16 CFR § 1500.3(c)(1)(ii)(C) defines highly toxic by the dermal exposure route, and § 1500.3(c)(2)(i)(C) gives the FHSA definition of toxic by the dermal exposure route. Section 1500.40 of 16 CFR details an in vivo method for testing the acute dermal toxicity of substances. Currently, there are no Commission-approved non-animal methods for dermal toxicity testing.Ocular Irritation Testing
- In Vitro Ocular Irritation Testing Methods
The Commission has voted to accept the recommendations of ICCVAM on several in vitro alternatives to the Draize rabbit eye test. The strengths and limitations of each method with respect to FHSA labeling requirements are described briefly here.
- The isolated chicken eye (ICE) test can be used as a screening tool for severe irritants/corrosive substances. When the ICE test indicates a substance is a severe ocular irritant/corrosive, that substance can be labeled "irritant" under FHSA with no additional testing. However, this assay cannot reliably distinguish all substances that require the FHSA irritant label (which include mild and moderate irritants) from substances not requiring the label. Therefore, if this screening test indicates the substance is not a strong irritant/corrosive, additional testing (i.e., a Draize test) would be necessary for validation and subsequent determination of labeling. The ICE test cannot be used to distinguish substances not requiring the FHSA irritant label from those requiring it. The ICE test cannot be used with alcohols, surfactants, or solids.
- The Bovine Corneal Opacity and Permeability (BCOP) test can be used as a screening tool for severe irritants/corrosive substances. When the BCOP test indicates a substance is a strong irritant/ocular corrosive, that substance can be labeled irritant under the FHSA with no additional testing. However, the BCOP test cannot reliably distinguish all substances that require the FHSA irritant label (which include mild and moderate irritants) from substances not requiring the label. If screening indicates the substance is anything but a strong irritant/corrosive, additional testing (i.e., a Draize test) would be necessary for validation and subsequent determination of labeling. The BCOP test cannot be used with alcohols, ketones, or solids.
- Cytosensor Microphysiometer (CM) test method can be used with water-soluble surfactant chemicals and certain types of surfactant-containing formulations (e.g., cosmetics and personal care product formulations, but not pesticide formulations) to distinguish substances not requiring the FHSA irritant label from those requiring the irritant label under FHSA. However, due to a substantial rate of false positive outcomes when the CM test method is being used for this distinction, a substance identified as an irritant would require additional testing in a valid test system (i.e., the Draize test) that can accurately characterize whether it requires hazard labeling.
- In Vivo Ocular Irritation Testing Methods
The Commission has approved a modified version of the traditional Draize rabbit eye test for ocular irritants. The traditional test guidelines are outlined in § 1500.42 of 16 CFR. Modifications to this method comprise a balanced three-part preemptive pain management strategy using topical anesthetics, systemic analgesics, and humane endpoints to avoid or minimize pain and distress associated with the traditional Draize method.
- Topical Anesthetics: Part one of the modified Draize eye test involves pretreatment of animals with a topical anesthetic and systemic analgesic before applying test substances. The ICCVAM-recommended protocol calls for administration of 0.01 mg/kg buprenorphine by subcutaneous injection 60 minutes before application of the test substance, plus 1 to 2 drops per eye of 0.5 percent proparacaine hydrochloride or 0.5 percent tetracaine hydrochloride five minutes before applying the test substance. This topical application can be repeated in 5-minute intervals, as needed, before test substance administration. However, ICCVAM qualified this recommendation with a warning that multiple applications could increase the severity or longevity of ocular lesions.
- Systemic Analgesics: The second part of the pain management strategy is adherence to a routine schedule of systemic analgesia after test substance administration. ICCVAM recommended a "rescue" dose of 0.03 mg/kg buprenorphine, given every eight hours, and 0.5 mg/kg meloxicam every 12 hours following test substance administration for a distressed animal. If the test animal is not in distress, ICCVAM's protocol called for 0.01 mg/kg buprenorphine, plus 0.5 mg/kg meloxicam, to be delivered subcutaneously 8 hours after test article administration. If ocular lesions and/or clinical signs of pain and distress persist after this combination dose, another dose of buprenorphine could be given at 12-hour intervals and another dose of meloxicam at 24-hour intervals.
- Humane Endpoints: The third part of ICCVAM's recommended pain management strategy was scheduled observations, monitoring, and recording of the nature, severity, and progression of all eye injuries. (One recommended eye irritation scoring system is the U.S. EPA's Test Guideline, OPPTS 870.2400: Acute Eye Irritation) (pdf).
ICCVAM recommended maintaining a written record of all observations to facilitate decisions on the progression or resolution of ocular lesions. Specific methods emphasized by ICCVAM to help detect and measure ocular endpoints included fluorescein staining, slit-lamp biomicroscopy, and digital photography. ICCVAM also identified specific ocular lesions indicative of a severity and irreversibility of damage that should warrant termination of studies before the end of the scheduled 21-day observation period, including:
- Draize corneal opacity score of 4 that persists for 48 hours;
- Corneal perforation or significant corneal ulceration, including staphyloma;
- Blood in the anterior chamber of the eye;
- Absence of light reflex that persists for 72 hours;
- Ulceration of the conjunctival membrane;
- Necrosis of the conjunctiva or nictitating membrane;
- Sloughing;
- Destruction of more than 75 percent of the limbus;
- Depth of injury to the cornea (routinely using slit-lamp and fluorescein staining)), in which corneal ulceration extends beyond superficial layers of the stroma;
- Vascularization of the corneal surface (i.e., pannus);
- No diminishment in area of fluorescein staining and/or increase in depth of injury over time; and
- Lack of re-epithelialization 5 days after application of the test substance.
Dermal Irritation Testing
- The traditional in vivo method for testing primary irritants is described in 16 CFR § 1500.41.
- In vitro methods assessing skin irritation and corrosivity have not been assessed by CPSC staff. The Organization for Economic Cooperation and Development (OECD) has written guidelines outlining in vitro methods for determining skin irritation and corrosivity, which are described in OECD Test Guidelines 430 and 431. Data generated using OECD Guidelines can be considered by CPSC in making a hazard determination as a result of the Mutual Acceptance of Data (MAD) agreement. The MAD agreement allows OECD member countries to mutually accept data that comply with OECD Test Guidelines and Principles of Good Laboratory Practice.
Sensitization Testing
16 CFR § 1500.3(b)(9) and 16 CFR § 1500.3(c)(5)(i) define the term strong sensitizer. The supplemental definition at 16 CFR § 1500.3(c)(5)(ii) references testing on humans and animals, as well as indicates using other types of data to support the determination of a substance as a strong sensitizer.Alternative methods for testing sensitization that have been approved by the Commission include:
- Murine local lymph node assay (LLNA);
- Reduced LLNA; and
- Two non-radioactive versions of the LLNA (BrdU-ELISA, LLNA:DA).
Commission Votes and other CPSC Approvals Pertinent to Alternatives to Animal Testing
The following are Commission votes or approvals made on behalf of the Commission, with respect to animal testing policy: