MedicalResearch.com Interview with: Adela J. Li, PhD Research Affiliate Wadsworth Center, Rm. D597 New York State Dept. of Health Empire State Plaza Albany, NY, 12201-0509 On the behalf of Dr. Kelvin Leung  MedicalResearch.com: What is the background for this study? What are the main findings?  Response: Most people love the beach. In order to block the sun’s damaging UV radiation, people generally slather on a thick layer of sunscreen against sunburn and skin cancer. Sunscreen is suggested to be re-applied every few hours regarding its effectiveness as well as being washed off into the water. These UV filters have been detected in the environment but most studies concluded that individual sunscreen chemicals pose no/low risk to animals or human. However, UV filters constitute a heterogeneous group of chemicals in sunscreens. We are wondering if combination of UV filters would induce higher toxicity than individual compounds, and whether these chemical interactions would develop over time, becoming increasingly dangerous to the living systems. Our study found seven of the nine UV filters in Shenzhen waters, China --- a rapidly urbanized city with over 20 popular recreational beaches, surprisingly, a reservoir and tap water. After exposing artemia to three dominant UV filters and then feeding these artemia to zebrafish adults, concentrations in both were up to 4 times higher when exposed to the mixtures than when exposed to only a single UV filter. A short-term of 25-day dietary exposure to the zebrafish adults did not appear to significantly influence early life stage development of the second generation; however, relatively long exposure over 47 days had significant adverse effects on embryo development. (more…)