Article

You, me and UV – introduction

Often we hear of ultraviolet radiation (UV) in the media. The message given is that it is a dangerous and invisible component of sunlight that is best avoided – too much UV of any kind can age our skin and cause various skin cancers. At the same time, we are told that sunlight is good for us as it triggers the production of vitamin D that we need to keep our bodies healthy.

Man sitting on sand under a yellow beach umbrella.

At the beach

A typical beach-side situation. How much UV radiation would there be shining on the person?

Rights: Johntex, GNU Free Documentation Licence

So what is ultraviolet radiation? Where does it come from? What effects does it have on the Earth and on our bodies? And can we put ultraviolet radiation to good use?

The electromagnetic spectrum

Ultraviolet (UV) light is part of a family of radiations called the electromagnetic (EM) spectrum. UV is produced naturally by very hot objects such as our Sun. UV shines on the Earth along with heat and visible light. Discover UV characteristics and how UV is monitored in What is UV?

Diagram of the electromagnetic spectrum.

The electromagnetic spectrum

The electromagnetic spectrum showing radio waves, microwaves, infrared, visible light, ultraviolet, X-rays and gamma rays.

Rights: The University of Waikato Te Whare Wānanga o Waikato

UV – the good and the bad

With the high rates of skin cancer in New Zealand, UV radiation is often presented in a negative manner. Get a quick overview in the article Positive and negative effects of UV.

UV is important for human health and useful in industry. Find out about its benefits: disinfection, curing substances, fluorescence, lighting and vitamin D.

Drying washing in the Sun on a line.

Washing in the Sun

Drying washing in the Sun helps to protect us from infection because some of the bacteria present in the washing are inactivated by exposure to UVB.

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UV exposure has negative effects. There is a clear link between UV and skin cancer. Melanoma, basal cell carcinoma and squamous cell carcinoma are three common types of cancer associated with UV exposure. Related articles explain why NZ skin cancer rates are so high, some of the risk factors and how skin cancer is diagnosed and treated. Human physiology associated with skin cancer is explained in articles about skin structure, cell division, the lymphatic system and mistakes in DNA.

Meet the scientists

Ultraviolet radiation features in many fields of scientific research. Professor Rod Dunbar and Dr Hayley Reynolds research melanoma and related skin cancers. Dr Gregory Bodeker and Dr Richard McKenzie monitor ozone levels and UV intensity. Sanjay Kumarasingham uses UVC light to disinfect Auckland’s wastewater.

Take up the challenge

Student activities cover many facets of ultraviolet radiation.

For those interested in protection from UV, begin with The face of melanoma, an activity that looks at lifestyle factors that contribute to skin cancer. Follow this with activities using the popular UV beads: UV bead items, Investigating UV intensity and Investigating sunscreens. There is also a unit plan covering this aspect of UV.

Invisible fluorescent ink under an UV light.

UV fluorescence

Information can be kept secret using invisible fluorescent ink that can only be seen under UV light.

Rights: The University of Waikato Te Whare Wānanga o Waikato

For those interested in the electromagnetic spectrum and the commercial uses of UV light, start with Write a secret message and Rock fluorescence. Make a printed circuit board uses UVA to cure (harden) a copper PCB. Wastewater polishing explores the effectiveness of UV treatment on sewage.

For those interested in cell division and mutation, try out Karyotypes and Modelling DNA.

Question bank

The You, me and UV – question bank provides a list of questions about ultraviolet radiation and places where their answers can be found. The questions support an inquiry approach.

Key terms

For explanations of key concepts, see You, me and UV – key terms.

Timeline

Explore the timeline to look at some of the historical aspects of our understanding UV and skin cancer. Find out how our understanding has changed.

Published:29 July 2008