Investigations on the emissions of biocides and PCBs under low volume conditions

•Dynamic conditions are essential for a quantitative SVOC analysis in air-tight showcases.•Diffusive sampling in air-tight showcases allows the detection of more SVOCs than active sampling.•By increasing the air sampling volume the amount of detectable higher boiling SVOCs is increased.•Increasing temperatures decrease the emission time above the corresponding limits of quantification. The aim of this study was the development of a low volume air sampling strategy for biocides and polychlorinated biphenyls (PCB) at low air change rates in modern, air-tight showcases as they are present in museums. Lindane, pentachlorophenol, dichlofluanid, tolyfluanid, isodrin, p,p-dichlorodiphenyl trichloroethane and permethrin were the biocides and PCB28 and PCB153 were the PCBs studied, all of which are semi volatile organic compounds (SVOC). Their occurrences in the museum environment originate from various sources e.g. preventive treatment of organic exhibits or organic building materials. Exhibits are long-term exposed to these pollutants due to storing in showcases or other storage equipment at low air change rates. To achieve air sampling under the aforementioned conditions the influences of temperature, air circulation, air change rate and relative humidity on the emission behavior of the selected biocides and PCBs had to be determined. This was carried out with pre-soaked wood samples in low volume air sampling experiments using 27L test showcases and 23L and 24L emission test chambers and also diffusive sampling with glass as the sampling material.