Over the years, the personal care industry has experienced many changes; perhaps none more profound or more justified than accepting increasing responsibility for the impact of its products on the environment. In fact, understanding and accepting the concepts of stewardship is a critical step in new product development.
As described by the ACTA consulting firm, which assists in making and using sustainable chemicals globally, product stewardship refers to the safe and effective management of chemicals throughout their lifecycle.1 “This is not only environmentally responsible, but is also increasingly requested by the public and required by governments worldwide,” the firm’s site explains. “To address public concern, governmental pressures and competitive demands, participants in the chemical manufacturing process must be proactive in managing and monitoring their products to minimize risk and safeguard the public from health and environmental hazards. Developing, maintaining and helping to evolve responsible product strategies are critical to the success of companies in the chemical space.”
The environmentally conscious movement has roots in the 1950s, which led to the culmination and publication of a book key to this phenomenon, written by Rachael Carson,2 entitled Silent Spring.3 Wikipedia states, “Silent Spring is an environmental science book published on September 27, 1962, documenting the adverse environmental effects caused by the indiscriminate use of pesticides. Carson accused the chemical industry of spreading disinformation, and public officials of accepting the industry's marketing claims unquestioningly. The result of her research was Silent Spring, which brought environmental concerns to the American public.”
Despite the fact that we have made many advances in our understanding of environmental issues, including the establishment of the U.S. Environmental Protection Agency (EPA)—which is chartered to protect people and the environment from significant health risks; to sponsor and conduct research; and to develop and enforce environmental regulations—there remains work to be done.
Properties in addition to those envisioned at the time Silent Spring are now being evaluated. These can be divided into four basic properties of an ingredient or raw material: 1) biodegradable, 2) sustainable, 3) readily commercially available and 4) green. These properties serve as the basis for the present discussion.
To address these topics with specificity, there must be an accepted definition, accepted testing methodologies, and accepted approaches to evaluate what this category means to the consumer, who after all, is the final decision maker in the personal care market. All raw materials used in the personal care industry can be modified to improve the values obtained for each of these categories by chemical modification; i.e., by placing groups within the molecule to improve the property desired.
As Mellou, et al., explain, “A global tendency for products considered environmentally sustainable and ecologically obtained [has] led the industry related to personal care formulations to fund the research and the development of personal care/cosmetics containing ingredients from natural resources. Furthermore, consumers are aware of environmental and sustainability issues…thus, not harming the environment represents a key consideration when developing a new cosmetic ingredient.”4
Biodegradation, i.e., biotic degradation or biotic decomposition, is the chemical degradation of contaminants by bacteria or other biological means, and is often referred to as the natural method of degrading discharged chemicals. Most biodegradation systems operate under aerobic conditions but a system under anaerobic conditions may permit microbial organisms to degrade chemical species that are otherwise nonresponsive to aerobic treatment, and vice versa.
Thus, biodegradation is a natural process or series of processes by which chemicals or other waste materials can be broken down or degraded into nutrients that can be used by other organisms. The ability of a chemical to be biodegraded is an indispensable element in understanding the risk posed by that chemical in the environment. Biodegradation is a key process in the natural attenuation, reduction or disposal of chemicals.5 Table 1 outlines the Organization for Economic Cooperation and Development’s (OECD’s) guidelines distinguishing six forms of biodegradation:6 ultimate biodegradation, primary degradation, readily biodegradable, inherently biodegradable, half-life time (T0.5), and disappearance time 50 (DT50). The full report on biodegradation is available online.7
Table 2 outlines recommendations for biodegradation testing.8 Upon review, three important factors are clearly required to successfully navigate the analysis:
1. Diversity of tests. A number of different tests must be available for potential selection and use.
2. Specification of the test. The test chosen for the evaluation must be identified.
3. Identification of the percentage of actives to be tested.
Additional terms used for products to describe their environmental fate include degradation for non-bio-based and hydrolyzable, and these also must be considered. An example of test data is shown in Figures 1 and 2 (figures and data courtesy of Covestro). The ability to review such data, as well as conclusions drawn from the data, is critical to understanding and supporting conclusions about it.
The article9 related to Figures 1 and 2 goes on to say: “Natural polymers are assumed by consumers to biodegrade better. However, just as for synthetic substances, the level and kinetics of biodegradation may strongly vary depending on the chemical structure of the polymer. Furthermore, natural polymers are often modified for the purposes of the application, which may significantly impair their biodegradability. This is sometimes the case with cellulose, which, when modified into carboxymethyl cellulose or hydroxyethyl cellulose, loses its ability to biodegrade with increasing degree of modification.”
Another factor to consider is the percentage of the raw material in a blend that is being tested. If a non-biodegradable product is being tested in a biodegradable solvent, the biodegradation conclusion may well be very different if that same material is tested neat. Again, proper definitions and conditions are critical.
All websites accessed on Feb. 4, 2020.
- ACTA. Chemical product stewardship. Retrieved from https://www.actagroup.com/index.php/practices/chemical-product-stewardship
- The Life and Legacy of Rachel Carson. Retrieved from https://rachelcarson.org
- Wikipedia. Silent Spring. Retrieved from https://en.wikipedia.org/wiki/Silent_Spring
- Mellou, F., Varvaresouand, A. and Papageorgiou S. (2019, Aug 1). Renewable sources: Applications in personal care formulations. Intl J Cos Sci. Retrieved from https://doi.org/10.1111/ics.12564
- ˇZupunski, M., ... Boriˇsev, M., et al. (2018). Insights and lessons learned from the long-term rehabilitation of abandoned mine lands—A plant based approach. Chemical Degradation. Retrieved from https://www.sciencedirect.com/topics/earth-and-planetary-sciences/chemical-degradation
- ECETOC. Technical report 123. Definition(s) according to OECD. Retrieved from http://www.ecetoc.org/report/measured-partitioning-property-data/biodegradation/definitions-according-to-oecd/
- OECD. (2005, Apr). OECD guidelines for testing of chemicals. Retrieved from http://www.oecd.org/chemicalsafety/testing/34898616.pdf
- ECETOC. Technical report 123. Summary and Recommendation. Retrieved from http://www.ecetoc.org/report/measured-partitioning-property-data/biodegradation/summary-and-recommendation/
- Pottié, L. (2019, Feb 5). Getting the breakdown: Testing the biodegradation and styling performance of polyurethane film formers. Cosm & Toil. Retrieved from https://www.cosmeticsandtoiletries.com/testing/toxicityanalysis/Getting-the-Breakdown-Testing-the-Biodegradation-and-Styling-Performance-of-Polyurethane-Film-Formers-505373421.html