HUMAN HEALTH RISK ASSESSMENT (HHRA)

The objective of the Human Health Risk Assessment is to select ingredients that will be used in our products that are safe for workers and consumers. Part of the assessment always is to anticipate accidents and potential for misuse. For any of the human health effects, a “no effect” level is established.

Exposure scenario Human Health Risk Assessment (HHRA) is a tiered process that progresses from the use of short-term tests (acute oral and dermal toxicity, skin and eye irritation, mutagenicity, sensitization potential) to longer-term (chronic) tests.

Human Health Risk Assessments continue until a product or ingredient is found to be safe, or until the use of the ingredient is no longer considered and alternative ingredients are explored and developed.

  • Human Health Risk Assessment - The Approach

    P&G risk assessment scientists address long and short-term exposure effects, assessing the probability of adverse effects from the use of its products (skin irritation, eye irritation, acute oral toxicity, acute dermal toxicity, allergic response, such as skin sensitization to long-term risks of mutagenicity, reproductive toxicity, neurotoxicity, and carcinogenicity).
    P&G scientists trained in risk assessments thoroughly assess the way(s) in which products may be used. For instance, we anticipate common accidents, such as a child swallowing a product or the splashing of a product into the eye. We also recognize that people sometimes make mistakes, like attempting to condition their hair with a product meant for fabric softening. Risk assessment scientists consider all these factors when evaluating the safety of our products.

    A critical consideration is the route and duration of exposure. The risk assessment addresses the probability of adverse effects from short-term exposures (for example, brief exposure to the skin, accidental ingestion, an eye splash) as well as long-term exposures (residues of detergents on clothing we wear each day, frequent hand-laundering, occupational exposures in manufacturing or processing).

    Scientists then assess the probability of adverse effects, given the types of exposures that have been anticipated. Potential short-term and long-term health effects may be evaluated, depending on the type of product and how it is likely to be used. Short-term effects include skin irritation, eye irritation, acute oral toxicity and acute dermal toxicity. The potential for the development of an allergic response, such as skin sensitization, is also assessed. An evaluation of the effects of the substance after repeated, long-term exposure is often necessary, and the metabolism of the compound may be studied to gain additional insight. Other effects that may need to be considered include neurotoxicity, immunotoxicity, reproductive and developmental toxicity and carcinogenicity. Comprehensive safety testing programmes may take months to years to complete.,br />
    However, because our scientists learn as much as possible from existing information, P&G resources are used wisely and testing is kept to a minimum.

    Since 1999, P&G have ended the use of animals in safety testing (except where required by law or when non-animal research alternatives were not available). This included the following products: colour cosmetics, dishwashing detergents, hair-care products, household cleaners, laundry detergents, skin care products and tissue and towel products.
    For more information, see P&G’s page on Animal Alternatives.

    • STEP 1: Review of Available Safety Information

      The Human Health Risk Assessment of individual ingredients is the foundation for the risk assessment of the products that contain them. Therefore, the first step in a risk assessment for new ingredients is a review of all available safety data from various sources. These sources include, but are not limited to: public on-line databases, toxicological reviews, information from suppliers, results from previously conducted testing on this or related substances and information about the metabolism of this type of substance.

      Once this review has been completed and the information analysed - a process that may take anywhere from several days to several weeks - a trained risk assessment scientist will make a preliminary risk assessment. The result of this exercise is the identification of missing information ("data gaps") and an understanding of which end points, if any, may require further evaluation. This helps the scientist to determine which toxicological areas should receive higher priority, and how the testing programme should be designed.

    • STEP 2: Exposure Assessment

      The characterization of potential human exposure is a critical component of the safety evaluation. Before the implications of any hazard can be assessed, it is necessary to establish the exposed populations and the levels, routes and duration of exposure that are relevant.

      We rely on two key numbers for each endpoint in the human health risk assessment: the exposure value and the no-effect level. The comparison of the exposure with the no effect level is used as an indicator of risk and can be expressed as the risk quotient or the safety margin.
      The concentrations of the product and its ingredients to which a person is likely to be exposed can be estimated from an understanding of the ways in which the product is manufactured, used, potentially misused and disposed of.
      Procter & Gamble has decades of experience in evaluating how consumers use its products. This experience often forms the foundation for characterizing exposure from intended uses of the product and reasonably foreseeable misuses. Occupational hygiene considerations and workplace monitoring provide the basis for assessment of workplace exposures. If relevant data are lacking, experimental models and chemical analyses may be employed under conditions that simulate the exposure in question. In addition, a variety of mathematical models are available for estimating exposure levels from indirect sources (such as air or drinking water) or specific exposure scenarios.

    • STEP 3: Safety Testing

      In the course of its history, P&G has collected a large historical database of information about the effects of its products. New products (also formulations) are systematically compared with this database (see Step 1: Review of Available Data). In July 1999, this investment paid off by enabling P&G to subscribe to the elimination of animal testing for all of its non-drug, non-food products. (P&G is a strong supporter of the development of alternative, in vitro test methodologies.)

      Once the potential hazards and exposures have been characterized, our scientists determine whether any testing will be required to substantiate safety. Safety testing programs are designed to address the most relevant potential hazards and conditions of exposure.

      Skin contact is the most common type of exposure for laundry and cleaning products. For this reason, P&G places much emphasis on the evaluation of skin mildness of its products. Skin irritation tests are designed to assess the potential irritancy to human skin after repeated contact with diluted or undiluted products. In order to ensure an adequate margin of safety, testing may be conducted under conditions that exaggerate potential exposure. In vitro test methods are used to assess skin irritation potential. In the final stage of the programme, clinical testing with human subjects can be conducted, to confirm that the product's mildness to skin is indeed what researchers had predicted it would be, based on the risk assessment.

      An important focus of the Human Health Risk Assessment is the prevention of allergies and skin sensitization. To assess the potential for this type of effect, P&G conducts specially designed sensitization tests. Clinical models, such as the Human Repeat Insult Patch Test, are also widely used. Because light is known to exacerbate allergic responses in some instances, photosensitization test protocols combine exposure to an ingredient or product with exposure to light under controlled conditions.

      The potential for short-term or long-term effects caused by dermal exposure is assessed by means of either single dose (acute dermal) or repeat dose studies in which the test substance is administered dermally, or through application onto the skin. During such studies, we are less concerned about local skin effects; rather, we are looking for systemic effects that result from the entry of the substance into the body. These studies can only be conducted with animals. If oral exposure is relevant, toxicity studies may be performed by this route as well.

      Where historical data do not suffice, eye irritation testing may be necessary to assess the effects associated with an accidental eye splash with a diluted or undiluted laundry or cleaning product. Detergent products may potentially irritate the eye to some extent. However, a long history of experience indicates that effects should be reversible within a reasonably short period of time. Therefore the test protocol prescribes that, in addition to an assessment of the seriousness of the effect, the duration for recovery is also measured. When testing is needed, we rely mostly on in vitro methods.

      Acute oral toxicity testing is conducted because of the possibility of accidental ingestion by a child or deliberate ingestion by adults (this is extremely rare). Interpretation of the test results requires knowledge of the amounts that are typically ingested accidentally by children. P&G has collected this information in the course of many years, with the help of Poison Control Centres and physicians. The test protocol consists of a single administered dose, after which the effects are monitored. If the test results indicate that a child may accidentally swallow a harmful amount of the product, precautions are taken, such as adding a child-resistant closure.

      A number of potential long-term effects may be considered during the risk assessment process. Some of these include immune effects, effects on the nervous system, reproductive toxicity (the ability to negatively affect the number of offspring), embryotoxicity (the ability to negatively impact the embryonic stage of development), teratogenicity (the ability to cause malformations in offspring) and carcinogenicity (the ability to increase the incidence of malignant tumours). When evaluating a product that may be used by many people for long periods of time, our toxicologists and risk assessment scientists must determine the need to evaluate a new substance for its potential to elicit various long-term effects. The development of a comprehensive safety programme is a matter of corporate responsibility and good corporate citizenship.

    • STEP 4: Risk Assessment

      Having reviewed the safety of ingredients and formulations, the risk assessment is performed. The risk assessor evaluates the probability that adverse effects may occur when a product is used as intended or in ways that can reasonably be foreseen. In order for a product to be approved for use, the risk assessment must demonstrate that the product is safe for its intended use and that an adequate margin of safety exists even if it is misused in a foreseeable way. All the toxicological end points that are relevant to the conditions in which the product is used must have been adequately addressed.

      In the best case, the risk assessment indicates that the ingredient or the product is ready to continue its journey towards the store shelves. However, if the risk assessment indicates that the ingredient or product does not meet P&G safety standards, the product will not be sold.

    • STEP 5: Introduction of the Product and Post-Market Surveillance

      Once P&G scientists have established and documented the safety of the product, it can be introduced onto the market. P&G provides a toll-free telephone number, which users can call to ask questions and share their experiences. P&G personnel responsible for safety monitor these calls to ensure that the experience in the market is as expected. In addition, studies are done in collaboration with Poison Control Centres.

      Our scientists promptly investigate any alleged safety questions to determine what type of problems may exist and how they should be addressed.

      Post-market surveillance provides continuous feedback that enables P&G to maintain a high standard of product quality and consumer satisfaction.

  • Human Safety Organization

    P&G’s Human Safety Organization employs scientists from diverse fields such as reproductive toxicology, immunology, respiratory toxicology, molecular biology, genotoxicity and carcinogenicity .

    More recently, genomics is being applied in the various toxicological disciplines in line with the latest trends in the field.

    P&G's researchers work closely with scientists at universities, governmental bodies and industry organizations to share their knowledge and work collaboratively on new and improved methods and approaches to advance the science of toxicology.

    Toxicologists at Procter & Gamble work at the leading edge of toxicology and human health risk assessment. They routinely publish their findings in peer-reviewed scientific literature.

    Procter & Gamble toxicologists' expertise in the area of human health risk assessment is regularly recognized externally.

  • Publications

    • Gerberick, G. F. and M. K. Robinson, 2000. A Skin Sensitization Risk Assessment Approach for Evaluation of New Ingredients and Products. Am. J. Contact Dermatitis 11(2):65-73.
    • Gerberick, G. F. and M. K. Robinson, and J. Stotts, 1993. An Approach to Allergic Contact Sensitization Risk Assessment of New Chemicals and Product Ingredients. Am. J. Contact Dermatitis 4(4):205-211.
    • Robinson, M. K., J. Stotts, P. J. Danneman and T. L. Nusair, 1989. A Risk Assessment Process for Allergic Contact Sensitization. Fd. Chem. Toxic. 27(7):479-489.
    • M.J. How et al., 1989. The A.I.S. Approach to Assessment of Product Safety. Tenside Surf. Det. 26(3):231-236.
    The following publications contain more details about testing protocols.
    • Rodriguez, C., G. Calvin, and C. Lally, 1994. Skin Effects Associated with Wearing Fabrics Washed with Commercial Laundry Detergents, J. Toxicol. - Cut. & Ocular Toxicol. 13(1):39-45.
    • Bannan, E. A., J. F. Griffith, T. L. Nusair, and L. J. Sauers, 1992. Skin Testing of Laundered Fabrics in the Dermal Safety Assessment of Enzyme-Containing Detergents, J. Toxicol. - Cut. & Ocular Toxicol. 11(4):327-339.
    • J. Stotts, 1980. Planning, Conduct, and Interpretation of Human Predictive Sensitization Patch Tests. In: Current Concepts in Cutaneous Toxicology, Academic Press, Orlando, 41-53.
    • Suskind, R. R., M. M. Meister, S. R. Scheen, D. J. A. Rebello, 1963. Cutaneous Effects of Household Synthetic Detergents and Soaps. Arch Dermatol, 88:117-124.

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