radiation processing for cultural heritage preservation ......apr 26, 2017 · horia hulubei...
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Radiation processing for cultural heritage preservation - Romanian experience Valentin Moise Horia Hulubei National Institute for R&D in Physics and Nuclear Engineering (IFIN-HH)[email protected]
International Conference on Applications of Radiation Science and Technology, 24 to 28 April 2017, Vienna, Austria
WOOD PAPER LEATHER TEXTILES FILM, PHOTO
ROMANIAN EXPERIENCE:
1. NEEDS FOR IONIZING
RADIATION TREATMENT
2. DOSE SETTING
BENEFITS
SIDE EFFECTS
RISK ASSEMENT
International Conference on Applications of Radiation Science and Technology, 24 to 28 April 2017, Vienna, Austria
WOOD - FURNITURE - ICONS -ARCHEOLOGICAL WOOD
WOODWORMS
FUNGI
International Conference on Applications of Radiation Science and Technology, 24 to 28 April 2017, Vienna, Austria
Detail of an Icon with heavy woodworms attack “Braila” Museum, Romania (2009)
Archeological wood attacked by fungi Pavement of a street in Old City, Bucharest (2015)
PAPER - BOOKS - ARCHIVES - WALLPAPER - Photography, Lithography
FUNGI
WOODWORMS / INSECTS
BACTERIA
International Conference on Applications of Radiation Science and Technology, 24 to 28 April 2017, Vienna, Austria
Wallpaper from “Aman” Museum Bucharest City Museums (2016)
Documents from ”Sahia Film“ archive Bucharest, Romania (2016)
LEATHER, TEXTILES, COMPLEX COLLECTIONS - book covers - clothing, garments
FUNGI
INSECTS
WOODWORMS
BACTERIA
International Conference on Applications of Radiation Science and Technology, 24 to 28 April 2017, Vienna, Austria
Leather book covers Parliament of Romania
Leather cover – (sec. XVII) Private collection, Romania
Clothing “Moldova” Museum, Iasi, Romania
FILM, PHOTOs, MAGNETIC TAPE
FUNGI
BACTERIA
International Conference on Applications of Radiation Science and Technology, 24 to 28 April 2017, Vienna, Austria
Film from National Film Archive, Romania Fotography from Bucharest National Theater
Efficacy Efficiency
High energy photons penetrates any material, at any depth, for any shape
Biocidal effect can be characterized by statistical means (lethal dose, D10)
Large quantities can be treated in short time, with low costs
Gamma irradiation
International Conference on Applications of Radiation Science and Technology, 24 to 28 April 2017, Vienna, Austria
Dose stetting: minimum dose – to achieve the biocidal effect maximum dose – to avoid or minimize side effects
BIOCIDAL EFFECT SIDE EFFECTS
Nu
mb
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of
su
rviv
ors
Dose
Ph
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ica
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ies
Dose
Irradiation geometry:
𝑫𝒐𝒔𝒆 𝑼𝒏𝒊𝒇𝒐𝒓𝒎𝒊𝒕𝒚 𝑹𝒂𝒕𝒊𝒐 (𝐷𝑈𝑅) =𝐷𝑚𝑎𝑥
𝐷𝑚𝑖𝑛
International Conference on Applications of Radiation Science and Technology, 24 to 28 April 2017, Vienna, Austria
Gamma irradiation
Insects infestation WOOD > 5 kGy* Polychromed wood < 10 kGy TEXTILES
Romanian Experience
1: Overkill dose
Rationale: - Lethal dose for insects : < 3kGy - No side effects for wood (ligno-cellulosic structure) up
to 50 key - Most of microorganisms (fungi) will be destroyed
Polychromed wood: - Most known pigments are stable up to 10 kGy - Non destructive tests are available: color changes (CIE
L*a*b*), FT-Raman (identification of pigments), FT-IR (substrate, binder, etc)
There is no efficacy test available but there is a large experience in wood radiation treatment
* Dose measured in accessible areas of the wooden item
International Conference on Applications of Radiation Science and Technology, 24 to 28 April 2017, Vienna, Austria
Fungi infestation: PAPER < 10 kGy LEATHER PHOTOS FILMS
Romanian Experience
2: Maximum dose limited by side effects
Rationale:
- Highly contaminated collections - No significant effects in physical properties of paper up to 10 kGy
Main side effect: Cellulose chain scission
Microbiological tests are available for evaluation of efficacy: - Bioburden test – total count (destructive - if allowed!) - Surface contamination – swab test, contact plate - Identification of microorganisms and determination of their
radiation resistance
International Conference on Applications of Radiation Science and Technology, 24 to 28 April 2017, Vienna, Austria
Benefits and side effects Treatment Benefits Side effects
Insect
disinfestation
• The active attack is stopped and there is no recurrence of insect infestation over the years (for more than 1000 items treated)
• No side effects for wood • No side effects for common old
pigments • Undiscernable changes of
proteins from wool (unpublished data)
Fungi disinfection • The active attack is stopped and microbial contamination is reduced to a safe level
• Decrease of average degree of polymerisation of cellulose from paper and other cellulosic fibers Undiscernable changes of collagen structure from leather (unpublished data)
International Conference on Applications of Radiation Science and Technology, 24 to 28 April 2017, Vienna, Austria
Efficacy of insect disinfestation: - No recurrence of insect infestation after the years
Examples:
Iconostasis from two churches highly attacked by woodworms (2002, 2005 – revisited in 2015)
“Aman” Museum wooden inventory (furniture, flooring, wainscoting, exhibits) with extensive woodworms attack. (2010 - revisited in 2015)
Carpets from “Mogoșoaia Palace” Musem (2015)
International Conference on Applications of Radiation Science and Technology, 24 to 28 April 2017, Vienna, Austria
1. bioburden testing before and after the treatment (Moise et al, 2012) (destructive, time consuming, costly, disregards “non-cultivable” microorganisms)
2. Testing the surface contamination before and after the treatment (recovers only a part of the total bioburden, disregards “non-cultivable” microorganisms)
3. Identification of main contaminants and estimation of treatment efficacy based on their radiation resistance (needs fungi database – in progress)
International Conference on Applications of Radiation Science and Technology, 24 to 28 April 2017, Vienna, Austria
Efficacy of fungi disinfection:
Treatment Dose (kGy) No of Log reduction
„Royal patents” Collection (Romanian State Office for Inventions and Trademarks, 2016) ~ 4 tons of documents
5.0 3
Treatment Dose (kGy) No of Log reduction
„Oficial Journal Collection” (Romanian Parliament Archives, 2014) ~ 4 tons of documents
Average: 6.6 > 3
„Museum inventory” (Bucharest National Theater, 2015) ~ 6 tons of documents, stage props, photos, etc
Minimum: 6.7
Maximum: 9.0
3
„Sahia Film Archive” (Romanian Ministry of Culture, 2016) ~ 3 tons of documents
Average: 6.8 5
Surface contamination:
Bioburden:
Side effects: Cellulose radiolytic degradation
scission g, e-
Charlesby, 1955: “random scission”
Bouchard et al, 2006: “the molecule cannot be cleaved precisely at the bombardment site”
International Conference on Applications of Radiation Science and Technology, 24 to 28 April 2017, Vienna, Austria
Experiments on paper: • Significant decrease of cellulose DP at low doses: 50-60% down for paper
irradiated at 10 kGy (Calvini and Santucci 1978, Adamo et al, 1998, Area et al, 2014) • No significant changes for macroscopic properties of paper: mechanical strength,
color, pH (Calvini and Santucci 1978, Adamo et al, 1998, Moise et al 2012) • Paper with very low DP (comparable with DP of cellulose in paper naturally aged,
3-400 years old) is less sensitive to irradiation than new paper (Bicchieri et al, 2016)
Reduction of size of cellulose molecules (decrease of DP – degree of polymerization) is associated with “ageing” of cellulose
Natural ageing degradation of cellulose is attributed to acidic hydrolysis process
In natural fibers, cellulose is packed (by hydrogen bonds) in a specific manner: micro-fibrils (supramolecular structures) and fibrils.
International Conference on Applications of Radiation Science and Technology, 24 to 28 April 2017, Vienna, Austria
The significant decrease of cellulose DP due to radiation treatment is not reflected in macroscopic properties of paper.
Possible explanation: acidic hydrolysis advances from the exterior of the cellulose structural units (fibrils, micro-fibrilis) and progressively destroy the hydrogen bonds structure, while ionizing radiation acts in entire volume of structural units and preserves the hydrogen bonds structure [Moise et al, 2014]
Side effects: Cellulose radiolytic degradation
Risk assessment - Help for decision for an intervention
International Conference on Applications of Radiation Science and Technology, 24 to 28 April 2017, Vienna, Austria
1. Initial risk assessment for paper documents under heavy biological attack:
No Hazard
P S IP Initial risk
Actions*)
Probability 1-unlikely 2-seldom 3-likely
Severity 1-negligible 2-moderate 3-critical
Priority
index PxS
1 - 3 low
4 - 6 medium 7 - 9 high
1 Total loss of physical integrity of documents and/or total loss of written information
2 3 6 HIGH
Radiation treatment 2 Documents are nor accessible due to health
hazard 3 3 9
No Hazard P S IP Residual risk 1 Total loss of physical integrity of documents
and/or total loss of written information 1 3 3
LOW 2 Documents are nor accessible due to health hazard 2 1 2
3 Side effects of the radiation treatment 2 2 4
2. Residual risk assessment after treatment:
Thank you for your attention!
Radiation processing for cultural heritage preservation - Romanian experience
Valentin Moise, Horia Hulubei National Institute for R&D in Physics and Nuclear Engineering (IFIN-HH)