BIOLOGICAL DETERIORATION

DEFINED Degradation of documentary materials resulting from activities of living organisms.

CATEGORIES 1. Micro-organisms i. Fungi 2. Macro-organisms i. Insects ii. Rodents

DETERIORATION BY MICRO- ORGANISMS 1. Types affecting documents i. Mold, Mildew or Fungi 2. Propagation i. Through Spores

FAVOURABLE CONDITIONS 1. Warm and humid condition 2. Temperature above 24 0 C 3. Relative Humidity above 65%

favorable conditions continued… 4. Continuous period of darkness 5. Little or no circulation of air 6. Pockets of stagnant air 7. Previously poorly treated infestation

SYMPTOMS Yellowish, greenish or/and brownish spots. Particularly on the spine of documents.

DAMAGES CAUSED 1. Fungi feed on the following: i. Cellulose ii. Starch iii. Adhesives iv. Sizing Materials

damages caused continued… 2. They weaken documentary materials – breaking them down. 3. They stain documents i. Temporarily ii. Permanently (Foxing – small brown dots)

4. Dangerous to custodians and patrons (diarrhoea) damages caused continued…

PREVENTIVE MEASURES 1. Keep documents clean. 2. Use air conditioning facilities 3. In the absence of air-conditioning: i. Maintain free circulation of air ii. Use wooden furniture

iii. Use dehumidifiers i. Electronic ii. Chemical iv. Do not shelve or file too tightly v. No leakage of water within or around the immediate exterior of storage area. Preventive Measures continued…

CURATIVE MEASURE Infestation may be at two levels. 1. Localized infestation 2. Universal infestation

Whatever the level of infestation; Fumigation using fungicide is the solution. Examples of Fungicides: Curative Measure continued… 1.Formaldehyde or Formalin 2.Thymol 3.Acetone

CONSIDERATIONS 1. Look for fungicide with low toxicity. 2. Look for those with little harmful effects. 3. Consider cost and availability.

EXPERT ASSISTANCE Always seek expert assistance to determine extent of attack and prescription of appropriate fungicide.

MACRO-ORGANISM Insects

ECONOMIC IMPORTANCE 1. Financial Implications i. Partial damage to documents – cost of repair ii. Total loss of documents – cost of replacement

2. Health Hazards – Custodians visiting Hospitals i. Hospital Bills ii. Loss of Man-hours 3. Psychological Revulsion i. Loss of Clients/patrons. Economic Importance continued…

TYPES OF INSECTS: 1. Habitual/Permanent Visitors 2. Occasional/Casual Visitors

Common Insects That Affect Documents: 1. Silver Fish 2. Book worms/Beetles 3. Book lice 4. Cockroaches 5. Termites 6. Mud wasps

Conducive Environment for Propagation 1. Warm and Humid Environment 2. Temperature above 21 0 C 3. Relative humidity above 65% 4. Long periods of darkness 5. Poor house keeping

6. Minimal Inspection 7. Minimal Use 8. Static Materials conducive environment for propagation continued…

How Insects Enter Storage Areas. 1. New intakes or accessions 2. Returned documents 3. Archival/Library boxes 4. Staff and clients 5. Fly ins (through doors and windows)

6. Cracks and crevices in walls 7. Cracks in foundations 8. Along sewerage lines 9. Old furniture How insects enter storage areas continued…

Indications of their Presence 1. Surfacial erosions of irregular shapes 2. Pile of fine powder on shelves/book cover 3. Small round holes on spine or cover 4. Tiny black droppings 5. Scratches on spine of books

6. Tiny bites at edges of documents 7. Occasionally, broken wings left behind 8. Mud tunnels on walls, shelves, furniture, etc. 9. Mud nests at corner of shelves, furniture and at times books. Indications of their presence continued…

Damages Caused to Documents 1. Total destruction – particularly termites 2. Partial destruction 3. Defacing documents 4. Staining documents – secretion, urine and droppings

Protection Against Insects 1. Make building insect-proof 2. Fit insect screens on windows 3. Seal all cracks and gaps in walls, windows and foundations. 4. Keep vegetation in the environment well kempt.

5. No live decorative plants in the information center 6. No food or eating in the office/center 7. Conduct periodic inspection 8. Constance vigilance by staff 9. Thorough inspection of in-coming materials Protection against insects continued…

10. Fumigate all new accessions 11. Periodic fumigation of the whole center or office 12. No bags should be allowed in the center. Protection against insects continued…

EXTERMINATION OF INSECTS Effective eradication of insects infestation is achieved through fumigation.

The whole storage area must be exposed to appropriate fumigant – insecticides. 1. Paradichlorobenzene 2. Ethylene-Oxide +CO 2 3. Mythyl Bromride

These may be toxic causing severe irritation to; 1. Skin 2. Eyes 3. Respiratory system

The current trend is the preference for non-toxic gases. Eg: 1. Carbon Dioxide 2. Nitrogen These stifle the oxygen supply to the insects and ultimately killing them