Carbonyl compounds indoors in a changing climate

Abstract

BackgroundFormic acid, acetic acid and formaldehyde are important compounds in the indoor environment because of the potential for these acids to degrade calcareous materials (shells, eggs, tiles and geological specimens), paper and corrode or tarnish metals, especially copper and lead. Carbonyl sulfide tarnishes both silver and copper encouraging the formation of surface sulfides.ResultsCarbonyls are evolved more quickly at higher temperatures likely in the Cartoon Gallery at Knole, an important historic house near Sevenoaks in Kent, England where the study is focused. There is a potential for higher concentrations to accumulate. However, it may well be that in warmer climates they will be depleted more rapidly if ventilation increases.ConclusionsCarbonyls are likely to have a greater impact in the future.

Indoor acids and bases

“…If present at sufficiently high levels, carboxylic acids can contribute to odor and irritancy 270 . Formic and acetic acids are among the most prominent and potent corrosive agents in air, so their abundance poses preservation threats for cultural artifacts 271 . Conservation challenges are amplified because hardwoods, such as oak, which might otherwise be favored for storage cabinets and display cases, can be strong emission sources 272 .…”

“…Because of the material‐damage risks posed, many studies of carboxylic acids have been conducted in museums and archives. The nature of the specific risks from formic and acetic acids in damaging cultural artifacts is well described by Brimblecombe and Grossi, 271 including “Byne's disease,” which refers to efflorescence of calcareous materials owing to their dissolution upon exposure to organic acids. Prosek et al 303 provide a useful introductory overview of corrosion risks associated with volatile carboxylic acids and also describe the development of a direct monitor “to assess small changes in air corrosivity in real time.” Graedel 304 described the corrosive nature of organic acid vapors for lead, indicating that “acetic acid [is] five to ten times as aggressive as formic acid.” In an interesting application of corrosion concerns, Niklasson et al 305 reported that “high concentrations of acetic and formic acid vapours are present in the wind system of the corroded [church pipe] organs.…”

“…270 Formic and acetic acids are among the most prominent and potent corrosive agents in air, so their abundance poses preservation threats for cultural artifacts. 271 Conservation challenges are amplified because hardwoods, such as oak, which might otherwise be favored for storage cabinets and display cases, can be strong emission sources. 272 Formic acid is an important oxidation product of atmospheric chemistry; comparing modeled to measured concentrations can help test and refine understanding of oxidative transformation processes.…”

“…The nature of the specific risks from formic and acetic acids in damaging cultural artifacts is well described by Brimblecombe and Grossi, 271 including "Byne's disease," which refers to efflorescence of calcareous materials owing to their dissolution upon exposure In contrast to formic and acetic acids, which have been extensively studied indoors, there is little published work reporting on the higher molecular weight carboxylic acids in indoor environments.…”

Analytical Approaches Based on Gas Chromatography Mass Spectrometry (GC/MS) to Study Organic Materials in Artworks and Archaeological Objects

“…Acetic and formic acid are the most abundant organic acids present in museum environments. Organic acids are dangerous for monuments and buildings [249], and acetic and formic acid in museum environments corrode lead, copper and some other metals and calcareous minerals [250][251][252][253][254][255].…”