Carbonyl and organic acid pollutants in the museum environment

Cecily M. Druzik, Dusan Stulik and Frank Preusser

Abstract

The role of art conservation is to protect objects from deterioration and damage. For this purpose, the artifacts are kept in environmentally controlled locations within museums, galleries, storage areas, and are enclosed in display cases or storage cabinets. This practice may cause problems when construction materials introduce substances into the environment or microenvironment that cause or accelerate deterioration. Substances known to cause damage to art objects are formaldehyde, acetaldehyde, formic acid and acetic acid. Sources of these deleterious substances in the museum environment are certain materials such as some woods and wood products, urea-formaldehyde resin insulation, paints, coatings and adhesives, paper-based laminates, fiberboards, fiberglas, crease-resistant textiles and paper products. If such materials are used in museum or display case construction without preventive measures or ventilation, concentrations of volatile organics can build up, and depending on the character of the displayed or stored art objects, damage to the art object can occur.

For several decades carbonyl compounds and organic acids have been recognized in the museum world as corrosive agents for lead objects, leaded bronzes, ethnographic objects, and a variety of other materials. Prior to the present study, most measurements of concentrations of carbonyl compounds and organic acids in the museum environment have been sporadic and not always quantitative. The development of high performance liquid chromatography and techniques for simultaneous measurement of concentrations at the parts per billion (ppb) level of carbonyl compounds and low molecular weight carboxylic acids in air has provided the tool for the systematic study of these pollutants.

Sixteen institutions participated in the present survey of carbonyl and organic acid pollutants. Participating institutions are located in Southern California, New York, Boston and Honolulu. The selection of institutions included a broad range of different museum architecture types and museum collections. The museums’ environments varied from open structures without environmental control to museums with highly sophisticated heating, ventilation and air conditioning systems.

Over 500 samples from 183 sites at the sixteen institutions were collected. The concentrations detected ranged from one to 200 ppb. In the majority of the locations sampled the concentrations were less than 10 ppb; however, there were a significant number of sites with high concentrations of carbonyl compounds. Samples were collected from four general areas or site types: galleries, storage areas, storage cabinets and display cases. In general, the concentrations of carbonyl and organic acid pollutants increased in the following order of site type: galleries, storage areas, storage cabinets and display cases. Concentration trends between pollutant pairs were detected: acetic acid was higher than formic acid, acetaldehyde was higher than acetic acid, formaldehyde was higher than formic acid, and formaldehyde was higher than acetaldehyde.