Tag Archives: featured

Fabiana Portoni publishes paper on the application of a technique to measure pesticide residues in contaminated museum artefacts

SEAHA aligned student Fabiana Portoni, alongside her supervisors Professor Matija Strlič and Dr Josep Grau-Bové, has recently published an article in the journal Heritage Science from Spinger Nature. The paper entitled “Application of a non-invasive, non-destructive technique to quantify naphthalene emission rates from museum objects” focuses on the development of an application to measure volatile pesticides residues in museum objects.

Insect pests can cause damage to museum collections. With the aim to protect objects from pest damage, it was once common in museums to use a wide range of pesticides. This was commonly practiced until as recently as the 1990’s. Nowadays, most museums steer away from using toxic chemicals on the objects. However, contamination from earlier treatments can still be a concern for people working with and accessing the collections.

In the last 30 years, the cultural heritage field has undertaken research to identify which pesticide residues remain in their collections and increase their knowledge regarding levels of contaminants present. Therefore, obtaining confirmed quantities of volatile organic residues, and their impact on the air quality surrounding objects, has been identified as an area that would benefit from further investigation.

Fabiana’s study analysed a group of organic objects from the British Museum collection with suspected contamination. After an initial screening to identify the pesticide compounds present in the objects, naphthalene was identified as the most common residue present. Therefore, it was decided to focus the research on this specific compound.

To ensure the long-term preservation of museum objects, it is preferable not to damage them by removing physical samples. The sampling methodology proposed in this study complied with this preference. In addition, the method proposed could be undertaken in situ at museum or heritage sites without impacting on the surrounding environment.

So what was the method? The technique required the object to be placed inside a sampling chamber. This chamber was fitted with an air pump. Air forced through the chamber by the air pump then passed through sorbent tubes. Volatiles emitted by the object could be collected into the sorbent tubes. Later analysis allowed identification of the volatiles and their concentrations.

The results for this research showed the concentration of naphthalene being emitted into the air over a period of time. Calculation of active emissions from individual objects is useful in understanding the behaviour of said objects and their impact on air quality in common museums situations. The information obtained was used to model the naphthalene concentrations for a period of time inside 3 common museum scenarios: a box, a display case and a storage room. The aim of gathering these results is to inform ventilation strategies and improve the dissipation of residues.

The paper states it would be interesting to use the method presented to asses a larger percentage of museum objects and get a relevant sample size of the collection.

To learn more about the project read the open access paper here!

 


Fabiana Portoni graduated from the MRes in Heritage Science at UCL Institute of Sustainable Heritage. She currently works as a Preventive Conservator for the British Museum.

SEAHA students present at the ICON conference in Belfast

The Institute of Conservation’s (ICON) triennial conference took place in Belfast from the 12th to 14th of June. Hundreds of delegates from numerous national and international universities, research institutes, conservation practices and heritage organisations were present for three days of conference sessions and special events. SEAHA was well represented, with papers by Cristina, Martin and Gavin. The Mobile Heritage Lab was also parked outside the conference venue, hosting demonstrations on participatory research, machine learning and the Oddy Test.

During the presentation titled “Simulation modelling: A learning laboratory for preservation management support”, Cristina introduced the use of simulation to explore the effect of preservation options during the lifetime of archival and library collections, regarding preservation, access and costs. The proposed approached, a hybrid model combining system dynamics and agent based modelling, captures the heterogeneity of the collections and allows the use of disparate data sources. The uncertainty level of the model when reliable data is not available was also discussed.

Martin presented research on Reigate Stone decay at the Tower of London. He used non-destructive testing and environmental monitoring to link observable decay patterns to distinct micro-climates. The findings will help determine the requirements of preventive conservation strategies.

The paper that Gavin presented at ICON was on his earlier work designing an algorithm for rock carving outlining and identification beneath lichen using Stonehenge as a case study. He also presented his current work using a supervised machine learning method to automatically identify the presence of carvings on bare rock surfaces.

The conference programme was huge. The first conference day saw guided tours of important heritage sites in and around Belfast, including the city’s street art and murals and Hillsborough Castle. The next two days saw 7 parallel sessions on topics ranging from textiles to ethnography, leadership to new conservators, and heritage science to collections care. These were book-ended by plenary sessions that included keynote presentations by Eleanor Schofield on the Mary Rose and Meredith Wiggins on #climateheritage.

With so much going on it was difficult to get an overall perspective, but it was clear that the conference was bursting with ideas and energy. This was a meeting place for long-standing colleagues and newly formed collaborations. Whilst the weather didn’t always play along, Belfast provided a vibrant backdrop with all the necessary infrastructure for keeping conversations going well past the last round of questions.

The conference ended on a unique high with the mysterious sounding ‘steam jazz night’. Delegates were taken for a ride up and down the Antrim coast on a genuine steam train. The train had been lovingly restored right down to the timber panelled wagons and was resplendent with personnel and passengers in period costume and a full jazz band. Every 20 minutes or so the train would stop at a small station and the ensemble would spill out, cakewalking, lindy hopping and boogying across the platform as the jazz band hit up a jaunty tune. It was a great way to round off this conference and create some stories to be retold at the next one in 3 years time.


Martin Michette is a DPhil student based at the University of Oxford in the School of Geography and the Environment. Martin is partnered with Historic Royal Palaces and Carden & Godfrey Architects. His project aims to develop preventative conservation strategies for Reigate stone at the Tower of London. 

Jenny Richards publishes research investigating the deterioration of earthen heritage by wind and rain

Oxford-based SEAHA student Jennifer Richards has recently published her research ‘a controlled field experiment to investigate the deterioration of earthen heritage by wind and rain’ in Springer Heritage Science.

Earthen heritage is one of the oldest and most universal forms of heritage with sites dating back to the Neolithic and being found of every continent. Earthen sites also make up 10% of the World Heritage List but are over represented on the World Heritage in Danger list in part due to the extensive deterioration occurring at the sites which threatens to reduce their value.

Deterioration of earthen heritage is affected both by material properties and environmental conditions. However, as conservation strategies try to limit the extent to which historic material is altered, more research is needed to understand how environmental conditions cause deterioration.

Wind driven rain, wind and sediment laden wind (wind which is transporting sediment) all drive the deterioration of earthen heritage with rain noted as causing the greatest rate of deterioration over short periods.

This study utilised a unique opportunity to undertake deterioration experiments at the remote and under-studied site of Suoyang Ancient City, Gansu Province, China. This study (i) compared effect of wind, sediment-laden wind and wind-driven rain in causing deterioration to earthen heritage and (ii) how the incipient deterioration features produced by wind, sediment-laden wind and wind-driven rain on the test wall relate to the deterioration features recorded on the historic city walls.

This research used a test wall built out of rammed earth to the East of the historic walls at Suoyang. The test wall was subjected the wall to low, medium and high intensities of wind, sediment laden wind and rain and laser scanning was used to assess the extent of the deterioration caused by each test run.

The deterioration features caused by each environmental force were notably different and could be mapped onto the historic walls. Clean wind caused the least deterioration and only removed loose material from protruding areas of the wall, while sediment-laden wind caused pitting (small concave features in the wall surface). Wind-driven rain caused the greatest deterioration with the formation of incipient gullies down the wall face. However, the low frequency of rainfall at Suoyang is likely to limit the extent to which rainfall can cause deterioration at the site, whereas the almost continual nature of erosive wind events suggests that wind may play an important role in causing deterioration even though it only has a low magnitude impact.

Further research is needed to understand how climate change will affect the environmental forces operating at Suoyang as increases in the frequency of rainfall or the speed of the wind could result in faster rates of earthen heritage deterioration. These findings show that conservation strategies at earthen sites like Suoyang need to address the impact of multiple environmental forces, such as clean wind, sediment laden wind and wind-driven rain.

Read the article here!


Header image: Jenny and her field work. Credit: Dunhuang Academy

Jenny Richards is a SEAHA DPhil student based at the School of Geography and the Environment at the University of Oxford. Her research, partnered with The Getty and Dunhuang Academy, evaluates site-based conservation approaches to mitigating climatic risks to earthen heritage sites in N W China.