Clean-and-Green Skincare Part 1. Typical Cosmetic Ingredients and What Is to Question

A quick look around your local, or online, cosmetics store will easily showcase how popular the emerging realm of clean-and-green skincare products has become. Over time, consumers have become increasingly invested in what ingredients are found or omitted in the skincare products they use. For their part, many manufacturers have also met the call toward making their manufacturing processes more transparent, while further integrating green sustainability measures. This article is divided into two parts: Part one will review common ingredients in many cosmetics and personal-care products. This part will also review two of the most common omitted ingredients in “clean” products: parabens and sodium lauryl sulfate. We will explore both the evidence and debates surrounding such exclusions. Part two—to come in the next Naturopathic Currents edition—will then dive into the notion of sustainability and how it plays a central role in clean-product development. Examples of what the industry may use as alternative ingredients will be reviewed, as well as resources to explore with your skincare professional to help identify clean-and-green products more easily.

The “Anatomy” of a Typical Cosmetic / Cosmeceutical Formula

To best appreciate the various ingredient concerns and, subsequently, greener alternatives to such ingredients, it is important to become familiar with some of the most common components of a typical cosmetic or personal-care product. The table below highlights these, alongside representative ingredients commonly used. What this section also seeks to show is the importance of appreciating exposure to such ingredients on a regular basis. It has been estimated, with each cosmetic product containing approximately 15–20 ingredients, that 5 cosmetic or personal-care products used daily amounts to roughly 75–100 ingredients applied to the skin each day. ¹ Some of those are found in multiple products, potentially providing for additive exposure.

Key Ingredients in a Cosmetic Formulation²

The “Free From” List: A Look at the Concerns and Debates Surrounding Them

It has become commonplace to find many cosmetics and personal-care products brandish a list of ingredients they exclude: For example, parabens, phthalates, sulfates, and benzophenone UV filters like oxybenzone. Interestingly, the growth in sales of such products has surged in recent years. We will explore a selection of such omitted ingredients, the evidence surrounding their health concerns, and, for some, counterpoints to such concerns.

Parabens and the Concern Over Hormonal Effects A Brief Overview:⁴

One of the most common preservatives used in cosmetics and personal-care products as well as in pharmaceuticals and even food. This is owing to several advantages, including providing a wide spectrum of antimicrobial activity, ease of use when formulating a product, being well-tolerated, and cost efficiency.

Common forms used in skincare include methylparaben, ethylparaben, propylparaben, and butylparaben.

Levels researched and regarded as safe for topical use of these common forms (by regulatory agencies in the European Union and in the U.S.):

• 0.40% or less for methylparaben or ethylparaben ([as acid] single esters and their salts).
• 0.14% or less for butylparaben and propylparaben ([as acid] single esters and their salts).
• 0.80% or less for combinations of these four parabens (with limitations placed on the sum of the individual concentrations of butylparaben and propylparaben).

Noted Health Concerns:

• Some in vitro (test-tube) animal studies (using oral feeding) and human trials have suggested the potential for certain adverse effects, such as endocrine (hormone) disruption, DNA-damage induction, increased estrogenic activity in human breast-cancer cells, histologic changes to prostate tissue, initiating oxidative stress within cells, toxic effects to sperm, reduced sperm counts, and effects on fertility, among others.⁵
• Specific to influencing endocrine levels, and the downstream effects that could impart, concern has been expressed for how endocrine disruptors may produce both a “cocktail effect” (representing the synergistic interaction between various substances) and an “additive effect” (representing the effects of the same ingredient being present across multiple products).⁶

Counterpoints to Such Concerns:

• Many studies suggesting adverse health outcomes on human populations were not specific to topical use, and likely represent environmental exposure (e.g., from food). Concerns over study quality have also been raised.⁷
• There is a large body of research which has not found a negative effect of parabens and have not been able to replicate earlier negative findings. ^8,9
• Many of the endocrine-disruption studies have been in vitro and animal-based, with adverse effects subsequently extrapolated to humans. However, the (oral) doses used in most animal trials were very high, further questioning extrapolation to humans. ¹⁰Additionally, the binding affinity of cosmetically used parabens to estrogen receptors is orders of magnitude lower than that of estrogenic hormones.¹¹
• Evidence demonstrating a direct negative effect on humans from cosmetic exposure is generally lacking.¹²

Sulfates and Fragrance Ingredients: Concerns Over Skin Irritation and Allergic Sensitization A Brief Overview:

• Sulfates, such as sodium lauryl sulfate and sodium laureth sulfate, are typically used as cleansing and foaming agents in products like skin cleansers / body washes, shaving creams, and shampoos / rinse-off products.¹³
• It is estimated that over 2,500 fragrance ingredients are used for cosmetics, personal-care products, perfumes, and colognes to impart an appealing product scent.¹⁴
• As mentioned above, even “unscented” products can contain fragrance ingredients to effectively mask the formula’s natural scent.¹⁵

Skin and Health Concerns:

• Sensitive/reactive, irritated, or inflamed skin can be worsened by the irritative effects of sulfates, in particular the sodium lauryl sulfate form since the sodium laureth sulfate form is generally better tolerated.^16,17
• Fragrance ingredients are among the most common causes of allergic contact dermatitis from cosmetic/topical skincare use.¹⁸
  • Skin-patch testing through an allergy-specialist physician can help confirm the presence of an allergic reaction to specific fragrance ingredients.
  • Unfortunately, in regions like North America, cosmetic manufacturers are not required to list individual fragrance ingredients. Instead, the term “fragrance” or “parfum” is all that is required to be listed. By contrast, cosmetics sold across the European Union are mandated to list 26 of the fragrance ingredients known to trigger contact allergies on their labels, if present above specific thresholds.¹⁹

Into the Unknown with “Forever Chemicals” (Per- and Polyfluoroalkyl Substances) A Brief Overview:

• A group of over 4,500 chemical compounds used in a wide variety of consumer and industrial products; also found in water supply, food packaging and food.²⁰
• Examples of where per- and polyfluoroalkyl substances (PFAS) are found include fabrics and carpets offering stain- and water-resistant properties (such as water-repellant sports gear), cleaning products, paints, nonstick frying pans, grease-resistant food packaging (such as lined fast-food containers), and even our water supply.²¹
• Examples of PFAS used in cosmetics include polytetrafluoroethylene (PTFE), perfluorooctyl triethoxysilane, perfluorononyl dimethicone, perfluorodecalin, and perfluorohexane, among many others.²²
• Intentional use in cosmetics is popular due to the water-repelling and film-forming effects which increase product resistance, durability, and spreadability; effect on product texture and consistency; while also smoothening skin appearance.²³
• Can be added to lipstick and other lip products, foundation, eyeshadow, eyeliner, mascara, lotions, cleansers, and nail polish, in particular those advertised as being “wear-resistant” and “long-lasting.”²⁴
• Unintentional presence in cosmetics can result from impurities present in the raw-material ingredients, as well as from the breakdown of PFAS ingredients which then forms other types of PFAS.²⁵
• In North America, there is no requirement for PFAS labelling on cosmetics.²⁶

Health and Environmental Concerns:

• A potential set of health concerns for various PFAS has been suggested based on preliminary research, including reproductive and developmental effects, effects on the endocrine system, and increased risk for cancers of the prostate, testes, and kidney.²⁷
• However, at this stage, so much more is unknown than is known regarding the confirmation that these health risks exist, and to what degree, with PFAS exposure.
• Specific to PFAS in cosmetics, what has yet to be fully determined is the toxicity of PFAS, if and how much they are absorbed through the skin, and the potential additive and adverse effects from topical exposure.²⁸
• Their ability for environmental persistence, such as in soil and waterways, has also raised concerns.²⁹