How Dangerous is Lip Balm?

There are myths that lip balm products are addictive, and this is true. Luckily, much of the public is aware of this, but don’t think it’s that huge of a deal. But how many people who use lip balm are aware of the chemicals that make it? In this article I will discuss each of the major ingredients in most lip balm products and assess how toxic they are and what effects they bring with them.

Butylated hydroxyanisole and hydroxytoluene

The first chemicals discussed that are found in most lip balm products are butylated hydroxyanisole and hydroxytoluene. These chemicals are used as antioxidant food additives in foods, which helps prevent the deterioration of food products. These chemicals are believed to be linked to endocrine disruption, organ-system toxicity, developmental and reproductive toxicity, cancer, and respiratory irritation (Toxic Ingredients). I’m going to find out if these claims are true.

A study done by Dassarma et al testing these chemicals on rats. Different variables were measured, and after the rats were exposed to the chemicals mixed with food, their AST, ALT, and ALP levels increased while SOD, CAT, and GPx levels decreased (Dassarma et al). These abbreviations are different types of biochemical markers are hormones and increases in their levels indicates particular diseases or abnormalities. Since the AST, ALT, and ALP levels increased, that meant that the “reacted oxygen species (ROS) mediated toxicity and pretreatment of butylated hydroxyanisole and hydroxytoluene restored the activity of the enzymes”. The conclusion of the study was that the antioxidants, which were the chemicals tested, did their job protecting the food while not harming the rats. What’s the takeaway from this study? The takeaway from the study is that the small concentrations given to the rats did not harm them. The same could be said for humans. However, that does not mean that we shouldn’t exercise caution with these chemicals, since rats do not have the lifespan of humans, so we could not anticipate what the chemicals would do to our bodies over the course of a lifetime.

Parabens

Parabens are commonly used as food preservatives due to their low toxicity and long history of safe use (Tavares et al). They are believed to have links to endocrine disruption due to their ability to “mimic estrogen, increased risk of breast cancer, and the development of the malignant melanoma (Toxic Ingredients). Propyl and butyl parabens have been shown to reduce sperm production and testosterone levels. A study conducted by Tavares et al tested the human effects of exposure to different types of parabens. Their results showed that parabens are harmful to humans, and that the “interaction between parabens and mitochondrial function in the testis that may be key in explaining the contribution of parabens for a decrease in reproductive potential” (Tavares et al). These parabens have been shown in reoccurring studies to continue to negatively affect the reproductive systems of the animals tested on, which indicates that the same is likely to happen to humans as well.

Perez et al tested parabens with the earlier mentioned chemical, butylated hydroxyanisole. These two chemicals in conjunction with one another had not yet been studied, so this is very indicative of the types of reactions we could be exposed to when using lip balm. The study set out to test whether a certain type of paraben, propylparaben, could prevent butylated hydroxyanisole from effecting “human cell viability and proliferation, oxidative stress, DNA damage and gene expressions” (Perez et al). The results of the study showed that butylated hydroxyanisole “potentiates the pro-oxidant effects of propylparaben in cultured mammalian cells”. Oxidative stress allows for an imbalance in the human body which leaves the host vulnerable to harmful effects of antioxidants. The pro-oxidant effects allow for this oxidative stress to occur. The disruption due to the oxidative stress allows for harmful chemicals to infiltrate more easily, causing a devastating effect.

Golden et al tested the effects of parabens on humans. The study tested the parabens to see how they interacted with vitro screening tests, “such as ligand binding to the estrogen receptor, regulation of CAT gene expression, and proliferation of MCF-7 cells” (Golden et al). A result obtained from this test was that uterine weight and male reproductive trace effects were increased. In relation to estrogen, a control variable in the tests, “the parabens had many orders of magnitude of activity less than estrogen. While there is a risk of an increase in adverse effects from increases in estrogen, it was speculated by Golden et al whether there would be these adverse effects because of increases of the parabens, despite having such a lower activity. Golden et al had to consider the potencies and doses of both estrogen and parabens to discover what the possible effects from the parabens were. It was necessary to properly correlate the amounts and effects since the activities are so different. Golden et al concluded that it was “implausible that parabens could increase the risk of any estrogen-mediated endpoint, including effects on the male reproductive tract or breast cancer” (Golden et al). Further analysis of the data were done and resulted in the conclusion that in the event of the worst-case exposure a human is expected to receive from parabens, they were at “substantially less risk relative to exposure to naturally occurring EACs in the diet such as the phytoestrogen daidzein”. This result indicates that parabens are not something to worried about in reference to the reproductive harms believed to be brought by these chemicals.

There is evidence on both sides showing that parabens may or may not be a major cause of disruption to the reproductive system, so the conclusion on how toxic this chemical is stands unresolved. A report from the International Journal of Toxicology studies parabens and their full effect to humans. They reported that parabens do not accumulate in the body. They determined from acute toxicity studies in animals that parabens are not significantly toxic to humans. This further supports Perez et al and their claims that parabens are not a huge thing to worry about. The fact that parabens do not bioaccumulate in our bodies is significant because it partially subdues the fear that future generations will always be affected by these chemicals. Of course, there is still the possibility that it could be passed down to children from parents, but if enough time has passed and the body has fully recovered from the exposure to the parabens, then there shouldn’t be a huge threat of it passing down. However, this does not mean that it cannot happen, and that people shouldn’t still be cautious.

Phthalates

Phthalates are found in the chemical makeup of the fragrance of lip balm products, and are believed to be reproductive disruptors. This is clearly evident from the study by Heindler et al that will be discussed shortly. Phthalates are also believed to cause weight issues with humans, by increasing body weight, growth rate, and food intake. Phthalates bioaccumulate in our bodies, which means that our body does not recover from exposure to these chemicals over time. This means that the effects of interactions with phthalates can easily be passed down from parent to child. A study composed by Heindler et al set out to determine the toxicity of microplastics such as polyethylene terephthalate and a placticizer known as Di(2-ethylhexyl)phthalate (DEHP). DEHP is a type of phthalate present in most lip balm products. The goal of this study was to test the toxicity of these materials on deep ocean organisms such as copepods, which are a species of plankton. While this study does not directly test for phthalate alone, we can see how the phthalate affects the organisms and the environment. The lip balm that we put on our lips could potentially make its way to the ocean by rubbing off from our lips to plastics such as water bottles. In the study, copepods were exposed to DEHP for 48 hours to assess how toxic the chemical is. As a result of this 48 hour exposure, the adult copepods were not affected even after large doses “up to 5120µg L-1” (Heindler et al), while the infant-stage copepods known as nauplii were “severely affected at very low concentrations (48h LC50value of 1.04 ng L-1)”. Although the adults appeared to PPPPPPP remain healthy after such a large dose, they were exposed to “sub-lethal concentrations of DEHP (0.1–0.3µg L-1) or microplastics (10,000–80,000 particles mL-1)”, resulting in an observed drop in egg production potential. Here’s one clear piece of evidence that shows reproductive issues can be caused by phthalates. Next, the copepods were exposed to microplastics and DEHP separately for 6 days with 18 days of recovery, and 24 days of exposure straight, to see how each chemical reacts with the organism and how the effects change with time. For the microplastics exposed for 24 days straight, there was a population status of “60±4.1%, p<0.001” of the original population, while the population decrease for the 6 days of exposure was at a status of “75±6.0% of control, p<0.05” of the former population, showing that the copepods were severely more affected by being exposed those extra 18 days. This same process was done for the DEHP chemicals, which are the ones found in lip balm. The significance of showing the microplastics data shows that it can be considered normal for organisms to show signs of recovery after being exposed to a chemical. This was not the case for the DEHP chemicals, where after 6 and 24 days, the results were practically the same at a population status relative to the original population of “59±4.9% and 59±3.4% compared to control; p<0.001” respectively. The significance and scary meaning of this is that this chemical bioaccumulates and can be passed down to subsequent generations, since the organism affected doesn’t recover from it. The harm that the chemicals bring to the organism affected include reproductive disorders, which is indicated that it could happen to humans the same it did for copepods.

A similar study was done with Yuan et al, where they tested the effects of DEHP on a type of catfish. The hepatic metabolism of the fish was monitored, which could be related to the liver in humans. The fish were “exposed to three levels of DEHP (0, 0.1 and 0.5mgL-1) for 56days” (Yuan et al). When exposed to the highest levels of DEHP, “final body weight, weight gain, specific growth rate and feed intake of fish” were higher than the other levels. This indicates that high levels of this phthalate could negatively impact our weight, along with all the other harms they bring.

Chemical sunscreen

Chemical sunscreen components such as oxybenzone, octinoxate, homosalate, and many more are ingredients in many lip balm products. The effects of these chemicals are believed to include endocrine disruption, sealing the skin in a way that enhances the effects of the other harmful chemicals, and reacts with chlorine in a harmful way. In a study composed by Bora et al, they tested the “sunscreen formulation comprising of four US FDA approved UV filters; namely avobenzone, octinoxate, oxybenzone, titanium dioxide along with melatonin and pumpkin seed oil” (Bora et al). These are all components of most lip balm products, since the products use them to give the lips protection from the sun. Using protocols from the Organization for Economic Cooperation and Development (OECD), Bora et al tested for “acute oral and dermal toxicity; skin sensitizing; skin irritating; ocular irritating and genotoxic potential”. Acute oral toxicity pertains to how the body reacts to consumption of the product and dermal toxicity pertains to how it affects the skin. Using the acute oral toxicity and dermal toxicity tests on adult Wistar albino rats, the LD50 (Lethal dose, or amount to kill 50% of the organism) for both toxicities were “˃2000 mg/kg”. The results of tests with other animals showed to be “non-sensitizing to the skin of guinea pigs and non-irritating to both skin and eyes of rabbits”. This indicates that these chemicals found in sunscreen are not immediately damaging to the skin on impact, but that does not mean that it couldn’t have long term effects on the skin.

Another study testing two chemicals in sunscreen, but also found in lip balm products: octylmethoxycinnamate (OMC) and butylmethoxydibenzoylmethane (BMBM). Montenegro et al tested these chemicals with the “in vitro release and skin permeation of two widely used UV-filters, octylmethoxycinnamate (OMC) and butylmethoxydibenzoylmethane (BMBM) from topical formulations with different features (oil in water (O/W) emulsions with different viscosity, water in oil (W/O) emulsion, oils with different lipophilicity)” (Montenegro et al). After being exposed to the sunscreen for 3 consecutive days, the “BMBM release from all these vehicles was very low, thus leading to poor skin permeation”. Similar results were found from the OMC, with the “vehicle composition significantly affected OMC release and skin permeation, and slight increases of OMC permeation were observed after repeated applications”. The levels of BMBM were “well beyond the accepted safety limit”, while the levels of OMC “may depend on the vehicle composition and the application pattern”. This study shows that both chemicals have the potential to affect skin permeation, by tightly sealing the pores of the skin in a while that could be harmful to humans. It can act as a barrier for other harmful chemicals from escaping the skin, enhancing the harm done by the earlier chemicals listed.

One report by DiNardo and Downs discussed oxybenzone, a component in sunscreens and lip balm products, and its potentially harmful effects to humans. They discussed how oxybenzone reacts with chlorine, “producing hazardous by-products that can concentrate in swimming pools and wastewater treatment plants” (DiNardo and Downs). This is a scary thought, considering an accidental mixture of lip balm with chlorine in water could create a reaction with the lips that sunscreen companies didn’t consider, since sunscreen isn’t applied on the lips. They reported that “oxybenzone has been reported to produce contact and photocontact allergy reactions, implemented as a possible endocrine disruptor and has been linked to Hirschsprung’s disease”. Here is another example of a component in lip balms believed to be linked to endocrine disruption. The conclusion of the report was that there is serious consideration that must take place when deciding to fight the risks of skin cancer without sunscreen, or all the” potential negative health and environmental effects caused by the accumulation of this and other chemicals in the ecosystem”.

The takeaway from this is that regardless of all of the uncertainty for the toxicity of the chemicals present in lip balm products, there are two certain ingredients that we absolutely should not be exposing our lips to, and those are phthalates and chemical sunscreen components. The data shown for the phthalates shows very compelling evidence that they are endocrine and reproductive system disruptors. The chemicals in sunscreen help enhance this harming effect because of the way they seal tight the pores in the skin making hard for the chemicals to escape. Unless you want to roll the dice on the dangers, I would suggest switching over to other products such as Vaseline or coconut oil.

References

Bora, N. S., Pathak, M. P., Mandal, S., Mazumder, B., Policegoudra, R., Raju, P. S., & Chattopadhyay, P. (2017). Safety assessment and toxicological profiling of a novel combinational sunprotective dermal formulation containing melatonin and pumpkin seed oil. Regulatory Toxicology And Pharmacology: RTP, 891–12. doi:10.1016/j.yrtph.2017.07.004

Dassarma, B., Nandi, D. K., Gangopadhyay, S., & Samanta, S. (2017). Hepatoprotective effect of food preservatives (butylated hydroxyanisole, butylated hydroxytoluene) on carbon tetrachloride-induced hepatotoxicity in rat. Toxicology Reports, 531–37. doi:10.1016/j.toxrep.2017.12.009

DiNardo, J. C., & Downs, C. A. (2018). Dermatological and environmental toxicological impact of the sunscreen ingredient oxybenzone/benzophenone-3. Journal Of Cosmetic Dermatology, 17(1), 15–19. doi:10.1111/jocd.12449

Final amended report on the safety assessment of Methylparaben, Ethylparaben, Propylparaben, Isopropylparaben, Butylparaben, Isobutylparaben, and Benzylparaben as used in cosmetic products. (2008). International Journal Of Toxicology, 27 Suppl 41–82. doi:10.1080/10915810802548359

Golden, R., Gandy, J., & Vollmer, G. (2005). A review of the endocrine activity of parabens and implications for potential risks to human health. Critical Reviews In Toxicology, 35(5), 435–458.

Heindler, F. M., Alajmi, F., Huerlimann, R., Zeng, C., Newman, S. J., Vamvounis, G., & van Herwerden, L. (2017). Toxic effects of polyethylene terephthalate microparticles and Di(2-ethylhexyl)phthalate on the calanoid copepod, Parvocalanus crassirostris. Ecotoxicology And Environmental Safety, 141298–305. doi:10.1016/j.ecoenv.2017.03.029

Pérez Martín, J. M., Fernández Freire, P., Daimiel, L., Martínez-Botas, J., Sánchez, C. M., Lasunción, M. Á., & … Hazen, M. J. (2014). The antioxidant butylated hydroxyanisole potentiates the toxic effects of propylparaben in cultured mammalian cells. Food And Chemical Toxicology: An International Journal Published For The British Industrial Biological Research Association, 72195–203. doi:10.1016/j.fct.2014.07.031

Tavares, R. S., Martins, F. C., Oliveira, P. J., Ramalho-Santos, J., & Peixoto, F. P. (2009). Parabens in male infertility-is there a mitochondrial connection?. Reproductive Toxicology (Elmsford, N.Y.), 27(1), 1–7. doi:10.1016/j.reprotox.2008.10.002

“Toxic Ingredients in Lip Balm.” f Toxins, 21 Nov. 2016, www.ftoxins.com/toxic-ingredients-lip-balm/.