Author: Hannah McGrath

SUNSCREEN SHOWDOWN: OXYBENZONE AND HOMOSALATE AND ZINC OXIDE… OH MY!

Hannah McGrath

Noah Kolander, Ichthyology Lab

Throughout most of recorded human history, we have not cared about the use of sunscreen. Or have we? It is now well known that the sun's rays can cause burns to the skin when left unprotected, but we have been trying to prevent such things for thousands of years. Initially, it was not to prevent cancer or getting sun spots but rather as a way to keep cool, prevent uncomfortable skin irritations, and, in some cases, prevent from looking like the lower class (Urbach 2001). Though trials were conducted in 1820, it wasn’t until 1900 that the same experiment was conducted where sunlight was split into “chemical rays” and heat. It was then that we realized that it was not just the heat that caused the burns but something different. This led to the invention of modern sunscreen derived from chestnut extract, which had been used in folk medicine for many years (Urbach 2001). Shortly after this revelation, in 1923, Coco Chanel returned from the French Riviera and accidentally tanned her skin, starting the craze of getting tan (BronzeTan.com 2020).

Fast forward to 2023, and we have more sunscreen and sunscreen ingredients than you can count with names that look like they came from an alien language. While not everyone is out trying to get a tan on the beach, everyone is directly affected by the sun's radiation every time they step outside. Fortunately, sunscreen technology has advanced to provide various types of sunscreen that can absorb or reflect the sun's rays, in addition to the wide variety of sun protection clothing that we have, there should be no reason for any of us to get burnt (Purohit 2017).

What seems like a straightforward solution to sun damage to the skin becomes less evident once you investigate the chemicals that make UV filtration possible.

There have been trials on the potential for active ingredients such as Benzophenone-3 (BP-3) to determine if this ingredient causes negative impacts (Watanabe 2015). The review found, though mixed results, altered birth weights and a decline in gestational age (Ghazipura 2017). I doubt any parent thinks that their sunscreen can cause gestational issues. Still, without further research, these products will continue to be sold and applied to the general public while potentially doing unknown harm to them.

(www.behealthynow.co.uk)

While human harm is a considerable concern, sunscreen and water are a pair that usually go together. On a deeper scale, sunscreen doesn’t stay put when applied to our bodies. Many sunscreen companies advocate applying more sunscreen after getting out of the water as it may come off in the water (Purohit 2017). When in the water, fish can bioaccumulate the active ingredients, disrupting endocrine function, altering behavior, and impacting development and reproduction (Lebaron 2022). Unfortunately, not all of these ingredients behave the same, and it is complicated to quantify each chemical's effect on every animal species. Aside from marine animals, studies examining marine algae’s response to BP-3 show decreased chlorophyll content and growth rate (Mao 2017).

Perhaps more commonly talked about is the effect that BP-3 has on corals. Each additional stressor adds to and exacerbates the preexisting problems in a changing climate. This, unfortunately, holds true for corals. Studies have demonstrated that BP-3 can damage all life stages of some species of corals and intensify the problem in the sunlight when most of the BP-3 pollution takes place (Downs 2017). The tourist industry that many island and tropical nations are built on is concurrently destroying the very thing that many tourists are coming to see.

This complexity intensifies the decision-making process when buying sunscreen. It involves not only considering the chemical impact of sunscreen on your body for cancer prevention or sunburn protection but also considering the broader environmental context. The ongoing issue of sunscreen-related pollutants in the environment has prompted some individuals to proactively address the matter, advocating for chemical removal methods directly from the environment.

There has been some success in wastewater treatment plants. BP-3 coming from pharmaceuticals and personal care products. The study used diammonium salt, a synthetic mediator, and acetosyringone, a natural mediator, which removed BP-3 to below a detectable level in just a couple of hours (Garcia 2011). There have also been pushes to use constructed wetlands to adsorb the chemicals or reduce them through biodegradation or plant uptake (Ilyas 2020).

Regardless of how we keep these chemicals from entering the ocean, one thing is certain: it must be done. Fortunately, ad campaigns have been somewhat successful, enacting specific chemical bans leading to lowered detection levels (Miller 2021). Sadly, there are no marketing standards or repercussions for mislabeling a bottle of sunscreen as “Reef Safe.” A study done in 2020 found that of the 52 products with a “Reef Safe” label, 48% of them contained a NOAA-specified “Reef Toxic” ingredient (Chi-Han 2020).

Further digging can reveal ingredients classified as non-hazardous (Miller 2021), but finding products containing only the listed ingredients can be difficult.

Even if you could find ingredients on the list provided in the Miller 2021 paper, that still does not mean that they are 100% reef and organism-safe. Chemicals affect different organisms in various ways, and currently, there is no standardized test that chemicals go through to determine if they are safe. The percentages of active ingredients differ from product to product, making classification more difficult. Is a 25% zinc oxide sunscreen better than a 4% BP-3 sunscreen? Without more research, these questions remain unanswered.

On sunscreen websites, the benefit to humans is frequently embellished and backed by dermatologists. Still, some scientific facts are stated without telling where they obtained their information (gowaxhead.com).

While there is still no clear answer about what sunscreen you should wear on your next outing, a few things are clear. More research is needed that should be performed by the companies that are advocating for their chemical use. Some sunscreens may be a better option such as non-nano zinc-oxide sunscreen, but overall, we must rethink sun protection and emphasize using material sun protection such as long-sleeved shirts, hats, and sunglasses.

(www.prevention.com)

References

BronzeTan.com. (2020, January 30). A Brief History of the Tan. Bronze Tan St. Louis. https://bronzetanstl.com/brief-history-tan/#:~:text=In%201923%20after%20accidentally%20tanning,and%20rebellions%20against%20Victorian%20values.

Chia-Han Yeh, M., Tsai, T. Y., & Huang, Y. C. (2020). Evaluation of ‘“reef safe”’ sunscreens: Labeling and cost implications for consumers. Journal of the American Academy of Dermatology, 82(4), 1013–1015. https://doi.org/10.1016/j.jaad.2019.10.059

Downs, C. A., Kramarsky-Winter, E., Segal, R., Fauth, J., Knutson, S., Bronstein, O., Ciner, F. R., Jeger, R., Lichtenfeld, Y., Woodley, C. M., Pennington, P., Cadenas, K., Kushmaro, A., & Loya, Y. (2016). Toxicopathological Effects of the Sunscreen UV Filter, Oxybenzone (Benzophenone-3), on Coral Planulae and Cultured Primary Cells and Its Environmental Contamination in Hawaii and the U.S. Virgin Islands. Archives of Environmental Contamination and Toxicology, 70(2), 265–288. https://doi.org/10.1007/s00244-015-0227-7

Garcia, H. A., Hoffman, C. M., Kinney, K. A., & Lawler, D. F. (2011). Laccase-catalyzed oxidation of oxybenzone in municipal wastewater primary effluent. Water Research, 45(5), 1921–1932. https://doi.org/10.1016/j.watres.2010.12.027

Ghazipura, M., McGowan, R., Arslan, A., & Hossain, T. (2017). Exposure to benzophenone-3 and reproductive toxicity: A systematic review of human and animal studies. In Reproductive Toxicology (Vol. 73, pp. 175–183). Elsevier Inc. https://doi.org/10.1016/j.reprotox.2017.08.015

Ilyas, H., & van Hullebusch, E. D. (2020). Performance comparison of different constructed wetlands designs for the removal of personal care products. In International Journal of Environmental Research and Public Health (Vol. 17, Issue 9). MDPI AG. https://doi.org/10.3390/ijerph17093091

Lebaron, P. (2022). UV filters and their impact on marine life: state of the science, data gaps, and next steps. In Journal of the European Academy of Dermatology and Venereology (Vol. 36, Issue S6, pp. 22–28). John Wiley and Sons Inc. https://doi.org/10.1111/jdv.18198

Mao, F., He, Y., Kushmaro, A., & Gin, K. Y. H. (2017). Effects of benzophenone-3 on the green alga Chlamydomonas reinhardtii and the cyanobacterium Microcystis aeruginosa. Aquatic Toxicology, 193, 1–8. https://doi.org/10.1016/j.aquatox.2017.09.029

Miller, I. B., Pawlowski, S., Kellermann, M. Y., Petersen-Thiery, M., Moeller, M., Nietzer, S., & Schupp, P. J. (2021). Toxic effects of UV filters from sunscreens on coral reefs revisited: regulatory aspects for “reef safe” products. Environmental Sciences Europe, 33(1). https://doi.org/10.1186/s12302-021-00515-w

Purohit , M. P. (Ed.). (2017, August 1). What type of sunscreen should I purchase?. DoveMed. https://www.dovemed.com/healthy-living/wellness-center/what-type-sunscreen-should-i-purchase

Urbach, F. (2001). The historical aspects of sunscreens. In Journal of Photochemistry and Photobiology B: Biology (Vol. 64). www.elsevier.com/locate/jphotobiol

Watanabe, Y., Kojima, H., Takeuchi, S., Uramaru, N., Sanoh, S., Sugihara, K., Kitamura, S., & Ohta, S. (2015). Metabolism of UV-filter benzophenone-3 by rat and human liver microsomes and its effect on endocrine-disrupting activity. Toxicology and Applied Pharmacology, 282(2), 119–128. https://doi.org/10.1016/j.taap.2014.12.002

Waxhead Sun Defense. (n.d.). Is zinc oxide safe? https://gowaxhead.com/blogs/the-thrive-lab/is-zinc-oxide-safe#:~:text=Zinc%20oxide%20is%20the%20only,and%20best%20active%20sunscreen%20ingredient.

Dive into Generosity: Moss Landing Marine Laboratories’ Day of Giving 2024

Hannah McGrath

Dive into Generosity: Moss Landing Marine Laboratories' Day of Giving 2024

By Hannah McGrath, MLML Oceanography Lab

Mark your calendars for the Moss Landing Marine Laboratories (MLML) Day of Giving on February 13th, 2024! As a renowned marine research facility and graduate program, MLML plays a pivotal role in advancing marine science and cultivating a passion for ocean conservation. The Day of Giving provides an incredible opportunity for supporters, alumni, and ocean enthusiasts to come together and support student scholarships, research and lab operations! 

Why Support MLML?

MLML has been a beacon of excellence in marine research for decades. Its interdisciplinary approach, cutting-edge research projects, and commitment to scientific outreach have made it a well known and respected institution. The funds raised during the Day of Giving will directly contribute to funding student research and opportunities including scientific diving equipment, boat time, laboratory equipment, and travel expenses to field sites and conferences (please watch the video attached to see where funds directly go). 

How Can You Contribute?

There are several ways for individuals to contribute to MLML community:

  • Monetary Donations: Contributions will go towards scholarships, research equipment, and maintaining MLML facilities.
  • Spread the Word: Share MLML Day of Giving information on social media platforms.  Encourage friends, family, and colleagues to join in supporting.
  • Engage with MLML: Attend our Open House on April 27th, 2024 from 9am - 5pm. This is a free, family-friendly event organized by MLML students and staff to engage with the surrounding community to showcase our research facilities, and share insights into marine science. 

Your support on the Day of Giving will have a lasting impact for students. It will provide scholarships for student research and equip MLML with the tools and resources needed to conduct research. 

Join the Day of Giving:

Mark your calendars for the Day of Giving on February 13th and the Open House on April 27th! Your generosity will significantly impact student research. 

Here is the link to  the Day of Giving page

Here is the link to the RSVP page: RSVP Form

 

Nature’s tiny heroes: how bacteria can devour plastic pollution in our oceans

Hannah McGrath

By Hannah McGrath, MLML Biological Oceanography Lab

Plastic pollution continues to be a growing issue on our planet, especially for our oceans. The global pandemic only contributed to our growing plastic problem. During the height of the pandemic, I remember walking along Riverside Park in New York City to escape my tiny apartment; the sidewalks and shorelines were littered with KN95 masks and light blue latex gloves. As I continued my walks throughout the pandemic, the sight of personal protective equipment scattered across the city became the norm. According to lead researcher Dr. Patrício Silva at the University of Aveiro, the pandemic dramatically increased the amount of plastic medical waste that has entered our aquatic systems. These plastics can then degrade into microplastics (< 5 mm in size) through physical, chemical, and biological processes which can have adverse effects on ecological and human health.

Although microplastics are small in size, they have a disproportionate effect on the environment. For instance, zooplankton which are important players in our ocean food webs and the biological carbon pump, a process that exports carbon to the deep sea, are threatened by microplastics. Zooplankton are able to consume microplastics which can damage their intestinal tracts, alter gene expression, delay growth, and impact feeding behavior resulting in decreased reproductive abilities according to lead scientist Dr. Meiting He at the College of Marine Sciences, South China Agricultural University. Unsurprisingly, microplastics have been identified in the gut content of organisms’ at almost all trophic levels from zooplankton to humans. Microplastics are in the clothing we wear, seafood we consume, beauty products we use, and more. In fact, in a 2019 study lead author Kieran Cox, a PhD candidate at the University of Victoria, estimated that ~39,000-52,000 pieces of microplastic are ingested by humans annually!

Illustration of microplastics (MPs) entering aquatic systems and being consumed by zooplankton resulting in the trophic-transfer of MPs up the food chain (He et al 2022). 

Not only is plastic pollution increasing but so is our need to adopt effective and sustainable ways for disposing plastics at a large scale. Current methods for plastic disposal are mismanaged and unsustainable. One common way to dispose of plastic is by incineration. However, during incineration plastics release carcinogens, dioxins, furans, heavy metals and sulfides into the environment states researchers Dr. Aubrey Chigwada and Dr. Memory Tekere at the University of South Africa. Another common method is dumping plastic waste into landfills but this causes plastic overflow affecting the biodiversity of the region. In addition, landfills store not only plastic waste but all types of waste that can decompose. During decomposition processes the potent greenhouse gas, methane, is released into the atmosphere which contributes to climate change. These landfills can also leak which can contaminate nearby groundwaters. Although recycling may seem like a promising way to dispose of plastics, at large scales it is too expensive and not feasible.

A more sustainable method to dispose of plastic is using microorganisms like bacteria that can biodegrade plastics. The first study that investigated microplastic degradation by microorganisms was Dr. Cacciari and his colleagues from the University of Tuscia in 1993. The researchers used the bacteria Pseudomonas and Vibrio to degrade polypropylene. Since 1993, many researchers have studied biodegradation of various plastics using bacteria from around the globe. Bacteria naturally exist in various environments from cow dung to human eyelashes to hot springs to polar ice caps making them suitable candidates for degrading microplastics. For instance, lead author Jun Yang at Beihang University, Beijing found two bacterial strains isolated from the gut of Indian mealmoths that were able to consume the plastic polyethylene.

Image of the two bacterial strains, Enterobacter asburiae and Bacillus sp. isolated from the gut of Indian meal moths (Yang et al. 2014).

Not only can bacteria naturally degrade plastics, but they can also be geoengineered to remove plastic from our oceans. Bacteria may just be nature's tiny heroes to combat plastic pollution. Currently, Professor Song Lin Chua and his colleagues at the Hong Kong Polytechnic University (PolyU) have bioengineered the bacteria Pseudomonas aeruginosa to remove microplastics from the environment. The researchers plan to use the sticky nature of bacteria to create “tape-like microbe nets” to capture microplastics. These microbial nets filled with microplastics then sink to the bottom of the water column. The bacteria’s biofilm dispersal gene is then engineered to release these microplastics from the biofilm traps. The bulk microplastics then float to the surface and are recycled. These preliminary experiments have been successful but have not been conducted outside of a controlled setting.

 

Schematic illustration of the bioengineered bacteria, Pseudomonas aeruginosa, removing microplastics from the water column using the 'capture-and-release' method developed by researchers at Hong Kong Polytechnic University

Although scientists are developing innovative ways to remove plastics from our ocean, there have been concerns about using bacteria to do this. Engineering bacteria to break down plastics especially in hot spots like the Pacific Garbage patch may reduce plastic waste, but may also have unintended consequences. For instance, breaking down microplastics may increase microplastic ingestion by other marine organisms like zooplankton that are known to consume microplastics. Another drawback is that the bacteria aeruginosa, that was used in PolyU preliminary experiments, carries diseases for humans’ states Professor Chua. Researchers are still searching for a bacterium that could be engineered that is natural and safe to humans at a large scale. But I am hopeful that scientists will find a safe and suitable candidate since bacteria are extremely abundant in the ocean. For every 1 ml of seawater there are ~1 million bacteria!

The reality is plastic pollution in the ocean is rapidly increasing. It is imperative that we find a solution to our growing plastic pollution problem sooner than later. Bacteria may just be one solution to our global plastic problem. However, more research and experimentation are still needed to understand the true benefits and consequences of genetically engineering bacteria to remove plastic from our oceans. Will bacteria be able to solve our plastic pollution problem?

 

References

Cacciari, I., Quatrini, P., Zirletta, G., Mincione, E., Vinciguerra, V., Lupattelli, P., Giovannozzi Sermanni, G., 1993. Isotactic polypropylene biodegradation by a microbial community: physicochemical characterization of metabolites produced. Appl. Environ. Microbiol. 59, 3695–3700. https://doi.org/10.1128/aem.59.11.3695-3700.1993

Chigwada, A.D., Tekere, M., 2023. The plastic and microplastic waste menace and bacterial biodegradation for sustainable environmental clean-up a review. Environ. Res. 231, 116110. https://doi.org/10.1016/j.envres.2023.116110

Cox, K.D., Covernton, G.A., Davies, H.L., Dower, J.F., Juanes, F., Dudas, S.E., 2020. Correction to human consumption of microplastics. Environ. Sci. Technol. 54, 10974–10974. https://doi.org/10.1021/acs.est.0c04032

He, M., Yan, M., Chen, X., Wang, X., Gong, H., Wang, W., Wang, J., 2022. Bioavailability and toxicity of microplastics to zooplankton. Gondwana Res. 108, 120–126. https://doi.org/10.1016/j.gr.2021.07.021

Liu, S.Y., Leung, M.M.-L., Fang, J.K.-H., Chua, S.L., 2021. Engineering a microbial ‘trap and release’ mechanism for microplastics removal. Chem. Eng. J. 404, 127079. https://doi.org/10.1016/j.cej.2020.127079

Patrício Silva, A.L., Prata, J.C., Walker, T.R., Duarte, A.C., Ouyang, W., Barcelò, D., Rocha-Santos, T., 2021. Increased plastic pollution due to COVID-19 pandemic: Challenges and recommendations. Chem. Eng. J. 405, 126683. https://doi.org/10.1016/j.cej.2020.126683

Yang, J., Yang, Y., Wu, W.-M., Zhao, J., Jiang, L., 2014. Evidence of polyethylene biodegradation by bacterial strains from the guts of plastic-eating waxworms. Environ. Sci. Technol. 48, 13776–13784. https://doi.org/10.1021/es504038a