Introduction

We often take for granted the artwork we see at museums. We see it in its current state and assume that it has always looked the same--the way the artist intended. However, we must remember that artwork, like all of antiquity, is at the mercy of time: time brings prolonged exposure to light, moisture, dust, and other elements of nature that cause artwork to become dirty and often permanently damaged. While most museums today are designed to protect artwork from these elements, the unfortunate problem is that the damage has already been done: centuries of storage in less-than-ideal conditions have greatly damaged some of the world's most important artwork. Engineers, however, are applying technology to the field of artwork restoration with exciting results. Two of these technologies, laser ablation and bacteria, have the potential to restore safely a work of art to its original condition, as it was conceived by the artist.

Effects of Aging

In order to understand the restoration process, we must examine why it is necessary in the first place. What happens to a work of art over the course of many years? A majority of older artwork has been subjected, at one time or another, to unfavorable storage conditions. Perhaps it hung in an old cathedral where it was exposed to centuries' worth of soot from incense and candles. It might have been kept in a smoky drawing room of a wealthy art patron. Regardless, the surfaces of artwork slowly accumulate dirt and soot over time, obscuring and distorting the original colors of the work. Moreover, in paintings, the clear layer of protective varnish that artists often apply over the paint tends to yellow and darken with time and exposure to light. Once the original transparency is lost, the varnish discolors the entire painting and is largely responsible for the "aged" appearance of older paintings (Smithsonian).

These factors, of course, are detrimental to the painting. Although the unattractive nature of dirt and soot is impetus enough for cleaning, the collection of contaminants on the surface of artwork can lead to quicker accumulation of pollutants as well as the development of mold or bacteria that can seriously harm the artwork. Fading varnish, if left unattended, can become so severe that the original painting is lost amidst a sea of dark yellow and brown (Smithsonian). Fortunately for art lovers, new technology is being developed to reverse these effects.