A wise young man once observed that the more confident Dad's feeling, the more he hangs his elbow out the window. This Father's Day, you might want to tell your dad that the king of the road deserves some air conditioning, as sun exposure while driving could lead to an increased risk of skin cancer.
University of Washington researchers analyzed data on cancer cases and found that people in the U.S. are more likely to develop skin cancer on the left side of their bodies. USA Today reports:
They found that when skin cancer occurred on one side of the body, 52% of melanoma cases and 53% of merkel cell carcinomas were on the left side. On the upper arms, 55% of merkel cell cases developed on the left side ... The National Cancer Institute says that in 2010 more than 68,000 people were diagnosed with melanoma, and 8,700 people died from the disease.
This finding is bolstered by previous research that found men who live in Australia, where people drive on the opposite side of the road, are more likely to get skin cancer on their right side.
Coauthor Paul Nghiem says glass windows should block most UVB rays, so if you drive with the windows up, you shouldn't have to apply sunscreen every time you drive. However, the researchers say those who are at a high risk for skin cancer or spend a lot of time in the car should think about slathering some of the more thoroughly regulated goop on their arms. The American Cancer Society also points out that windows block a smaller portion of UVA rays, and while less intense than UVB rays, these can still damage the skin over time. So if you want to err on the side of caution, feel free to douse yourself in sunscreen on a daily basis.