NADD - An association for persons with developmental disabilities and mental health needs

From the NADD Bulletin Volume XI Number 4

Sunscreen, Nanoparticles, and Individuals with MI/ID

Larry Livingston Ph.D., University of Illinois-Springfield

Individuals with MI/ID often require psychotropic medication to control maladaptive symptomology (including aggression, property destruction, self-injury, and pica) and to improve their adaptive functioning. But several classes of psychotropics can increase an individual’s risk for sunburn, including members of the antipsychotic, antidepressant, and mood stabilizer families (RX List, 2008). Application of sunscreen can minimize an individual’s risk for sunburn and skin cancer, but experts have expressed concern over the use of nanoparticles in sunscreen (Amato, 2004; Burfeind, 2007; Consumer Reports, 2007a). Individuals with MI/ID may have an impaired ability to communicate symptoms of developing sunburn; caregivers who fail to protect their patients from sunburn could be charged with medical neglect. This author is aware of an incident involving a resident with MI/ID who was thought to have boarded the bus to the day program, but who instead went and sat in a nearby swing. This was unnoticed by the caregivers. The day program assumed the individual stayed home. The error was not discovered until the bus returned, six hours later. The resident had second degree burns and was dehydrated; one caregiver was fired and one disciplined.

Nanotechnology: Promise and Danger

Nanotechnology offers promise in many areas, including drugs that could seek out and destroy cancer cells, molecular “ink” that could encode millions of pages of information in a square inch, and contact lenses that let you check your blood sugar by just looking in a mirror (“Nanotechnology: Untold Promise, Untold Risk,” 2008). Nanotechnology works in two main ways: materials can be vastly reduced in size, or scientists can manipulate individual atoms and molecules, forming microscopic tubes, spheres, wires, or films. But materials can change properties when reduced. Carbon becomes 100 times stronger than steel, aluminum becomes highly explosive, and gold melts at room temperature (Consumer Reports, 2007a). Britain recently prohibited the term “organic” from being applied to products containing nanoparticles, affording consumers there some level of protection (Cookson, 2008).

Nanoparticles in Sunscreen

Nanoparticles of titanium dioxide and zinc oxide, used in many sunscreens, are suspected of causing neurotoxicity. Researchers have found that such exposure can cause oxidative stress, a mechanism implicated in certain neurodegenerative diseases including Alzheimer’s, Amyotropic Lateral Sclerosis, and Parkinson’s (Long, Saleh, Tilton, & Veronesi, 2006; Block & Hong, 2005). Titanium dioxide nanoparticles have been shown to produce oxidative stress toxicity in human cells, including those of the colon (Zhang & Sun, 2004) and bronchi (Gurr, Wang, Chen, & Jan, 2005).

Sun care products account for 5.5% of the $253 billion personal care products market. Manufacturers use nanoparticles of titanium dioxide or zinc oxide in sunscreen because this allows the final product to be transparent, rather than an opaque white, which consumers prefer (Newman, 2006). Interestingly, sunscreens containing nanoparticles are no more effective in protecting against sun damage than nanoparticle-free sunscreens (Burfeind, 2007; “Sunscreens: Some Are Short on Protection,” 2007). Laboratory testing of eight sunscreens which listed either titanium dioxide or zinc oxide as ingredients found that all contained nanoparticles of these chemicals, despite the fact that only one disclosed the use of nanotechnology on their label (Consumer Reports, 2007b).

Conclusions

Individuals with MI/ID who receive psychotropic medication are more vulnerable to sunburn than the general population. The use of sunscreen can protect these individuals from sunburn and reduce their risks of developing skin cancer. Sunscreen containing titanium dioxide or zinc oxide may expose the wearer to nanoparticles, which are considered unsafe by experts. Many sunscreens containing nanoparticles are not labeled as such. A safer and equally effective choice would be a sunscreen containing neither titanium dioxide nor zinc oxide.

Sources

Amato, I. (2004). Nano’s safety checkup. Technology Review 107 (1) 22.

Block, M.L. & Hong, J.S. (2005). Microglia and inflammation-mediated neurodegeneration: Multiple triggers with a common mechanism. Progress in Neurobiology 7 (1) 77-98.

Burfeind, D.B. (2007). Group warns of danger in sunscreens. Dermatology Nursing

19 (6) 575.

Cookson, C. (2008, January 15). Organic body bans use of ‘nanoparticles’. Financial Times, p.4.

Gurr, J.R., Wang, A.S., Chen, C.H., & Jan, K.Y. (2005). Ultrafine titanium dioxide particles in the absence of photoactivation can induce oxidative damage to human bronchial epithelial cells. Toxicology 66 (8) 66-73.

Long, T.C., Saleh, N., Tilton, R.D., Lowry, G.V., & Veronesi, B. (2006). Titanium dioxide (P25) produces reactive oxygen species in immortalized brain microglia (BV2): Implications for nanoparticle neurotoxicity. Environmental science & Technology 40 (14) 4346-4352.

Consumer Reports. (2007a). Nanotechnology: Untold promise, unknown risk. Retrieved April 27, 2008 from http://www.consumerreports.org/cro/health-fitness/nanotechnology-7-07/overview/0707_nano_ov_1.htm

Newman, K.A. (2006). Sun protection: Global dynamism continues. Global Cosmetic Industry 174 (12) 32-34.

RX List: The internet drug index. Retrieved April 1, 2008. Web site www.rxlist.com .

Consumer Reports. (2007b). Sunscreens: Some are short on protection. Retrieved May 1, 2008 from http://www.consumerreports.org/cro/home-garden/beauty-personal-care/skincare/sunscreen-7-07/overview/0707_sunscreen.htm

Zhang, A.P., Sun, Y.P. (2004). Photocatalytic killing effect of TiO2 nanoparticles on Ls-174-t human colon carcinoma cells. World Journal of Gastroenterology 10, 3191-3193.

For further information, contact Dr. Livingston at llivi1@uis.edu.

The NADD Environmental Health Project, funded by the John Merck Fund, provides professionals, families, and the general public with relevant information concerning toxic agents and their affects on neuro-development. For further information visit www.thenadd.org and click on “Environmental Health Project,” or contact Ed Seliger, Project Coordinator, at eseliger@thenadd.org.