When temperatures rise, many seek relief in going for a swim, secure in the knowledge that lifeguards are thereto protect them and bring safety to the pool or lakeside. However, these guardians are at great risk themselves. There are numerous dangers to being a lifeguard. Many of these risks are genotoxic, that is, they have a deleterious effect on the genetic material of a cell. The most prominent genotoxic effects are caused by long hours in the sun and hazardous by-products of both pools and lakes.
One of the major genotoxic risks to lifeguards is constant exposure to UV radiation from sunlight. The danger of UV light is that, because of its high energy, it can ionize molecules (converting them to ions by removing or adding charged particles) and thus induce chemical reactions in the skin, which can cause many harmful effects in the body. Approximately 90% of UVB and nearly all of UVC rays are absorbed by the ozone layer in the earth’s atmosphere. UVA makes up 95% of UV radiation that reaches the earth. When UV radiation reaches the skin, its ionizing energy is absorbed by a variety of molecules including a cell’s DNA. Over time, the absorption of ionizing radiation by a cell’s DNA can result in accumulation of genetic mutations,eventually transforming the cell to a cancerous one. While UVA penetrates more deeply into the dermis and damages both the epidermis and dermis, UVB has biological effects 1,000 times stronger than UVA.
Phototoxicity is another issue faced when dealing with UV radiation. Chemical photosensitivity refers to an adverse reaction in the skin that results when certain chemicals or drugs are applied at the same time that a person is exposed to UV radiation. Phototoxicity is a form of chemical photosensitivity and phototoxic agents are activated in the UVA range. Consequences of exposure to a photosensitizing agent can range from uncomfortable, serious, or life-threatening.
Aware of the harmful effects of sunlight, many pool-goers will apply sunscreen and then spend hours in the sun, thinking that they are fully protected. Unfortunately, sunscreen may not fully protect the skin as well as one might think. Sun Protection Factor, or SPF is the most common way to determine the effectiveness of a sunscreen. This level reflects protection against erythema, skin redness caused by swelling of the capillaries. SPF quantifies the protection that a product can offer in terms of exposure time in relation to sunburn when compared to unprotected exposure. For example if sunscreen has SPF 30, a sun exposure 30 times greater is necessary to produce erythema. However, the dosage to be applied, maintained by the FDA (about one ounce for an average adult), is shown to be far more than what the average person applies.
Another danger lifeguards are exposed to is the detrimental effects of chlorine. Chlorine is used in pools to disinfect them. However, chlorine reacts with organic and nitrogen compounds like hair, sweat, lotion, and saliva to form chlorination by-products (CBPs). Some of these CBP’s can be transferred from water to air. Several studies have found an association between exposure to elevated Trihalomethanes, (THMs), which are common CBPs, and adverse health effects including irritations of the eyes, skin, nose and throat, as well as adverse reproductive effects. In order to try and resolve this issue recent studies have also showed decreasing pH of the pool reduced the formation of THMs. Unfortunately, this may not be an entirely practical solution, as the pH for a pool has to be maintained at a certain level in order to maintain a safe environment for swimmers.
Furthermore, in a recent study, commercially available sunscreen product was exposed to chlorine, a common disinfectant in pools. The results showed that active ingredients in some sunscreens can react with chlorinating agents, generating new species that are toxic to cells.
Swimming in a lake, rather than in a pool, comes with its own health risks. One is harmful algal blooms (HAB). These blooms are harmful and they create public health risks for swimmers by producing very potent toxins, which include neurotoxins, hepatotoxins (chemicals that cause damage to the liver), and carcinogens. Efforts to develop technology that will be able to determine when a harmful HAB event has occurred is underway (Trainer 2008). In addition to HAB there are other threats associated with coastal waters, including pathogens such as bacteria, viruses, and parasites associated with fecal contamination of water. There are also naturally occurring water-borne chemical toxicants and pathogens that can adversely affect people who use the water such as arsenic (a heavy metal) and vibrios (bacterial pathogens).
Although they are there to protect others, lifeguards face many dangers in their seasonal occupation. There are always emerging studies showing new developments in how to prevent these harmful effects. This new data will continue to improve and make this notable profession a safer one.
Andersen, H.R., Hansen, M.S.K, Willach, S., Mosbaek, H., “Particles in Swimming Pool Filters- Does pH Determine DBP Formation?” Chemosphere. 87.3 (2012): 241-47. Print.
Balk, S.J., “Ultraviolet Radiation: A Hazard to Childeren an Adolescents.” Pediatrics. 127.3 (2011): 791-817. Print.
Bessonneau V., Derbez M., Clement M., and Thomas O., “Determinants of Chlorination By-products in Indoor Swimming Pools.” International Jounal of Hygiene and Environmental Health. 215.1 (2011): 76-85. Print.
Gast, R.J., Wilcox, B.A., Younglove, G.R., Tsuchiya, A., Hoagland, P., Faustman, E.M., Backer, L.C., Fleming, L.E., Kite-Powell, H.L., “Linking the Oceans to Public Health: Current Efforts and Future Directions” Environmental Health. 7.2 (2008): 6. Print.
Goodarzi, H., Maverakis, E., Miyamura, Y., Bowen, M.P., Correa, G., Ono, Y., “Light, Including Ultraviolet.” Journal of Autoimmunity. 34.3 (2010): 247-257. Print.
Hartemann, P., Floretin, A., “Health Effects of Disinfection By-Products in Chloronated Swimming Pools.”, International Jounal of Hygiene and Environmental Health. 214.6 (2011): 461-69. Print.
Puizina-Ivic, N., “Skin Aging.” Acta Dermatoven APA. 17.2 (2008): 47-54. Print.
Schalka, S., and V.M. Reis., “Sun Protection Factor: Meaning and Controversies.” Bras Dermatol. 86.3 (2011): 507-15. Print.
Sheaff, R.J., Purser, G. H., et al., “Altered UV Absorbance and Cytotoxicity of Chlorinated Sunscreen Agents.” Cutaneous and Ocular Toxicology. (2012). Web. 27 Apr. 2012. <http://informahealthcare.com/doi/full/10.3109/15569527.2011.647181>.
Trainer, V.L., Brand, L.E., Moeller, P., Parker, M.S. et al., “Centers for Oceans and Human Health: A Unified Approach to the Challenge of Harmful Algal Blooms.” Environmental Health. 7.2 (2008): 2. Print.