Last reviewed 18 April 2016
It is not something most of us would think to worry about but historical artefacts can pose a serious health and safety risk when handled. Sebastian Mazurczak looks at the risk and type of hazards that can arise when dealing with such items of historical value.
Historical artefacts are a window to a time in history and can make major contributions to the significance of places. As part of our heritage, they are therefore valuable and should be preserved. However, some historical items have the potential to cause harm if not handled properly. They could be poisonous, carcinogenic or hazardous.
Generally the hazards associated with historic items can arise from three factors, as a result of:
constituent materials, eg minerals that are naturally radioactive or carcinogenic
deterioration, ie items perfectly safe when in a stable condition can become hazardous and release toxins as they deteriorate
previous procedures carried out in the past to preserve them.
Identifying the risk of exposure
Often with collections of historical items, the potential hazards have never been properly identified. Dangerous substances can be absorbed by the body by means of inhalation, ingestion, through the skin or a combination of these routes of entry.
Inhalation: when handling aged materials in poor condition, hazardous dust, mould spores or surface toxic chemicals can be breathed in. Certain materials release toxic gases when they degrade.
Ingestion: occurs mainly due to poor hygiene practices, by first handling items then handling food or touching one’s face and mouth. Dormant diseases can reactivate within the body as in case of anthrax spores, which could be present lying dormant on animal hides. Poisons could be swallowed when handling chemically treated items.
Absorption: where toxins can pass through the skin and enter the bloodstream. This is more likely in the case of radioactive substances, some pesticides and other chemicals.
The severity of risk depends on the concentration of a substance, the toxicity of the contaminant and the likelihood of exposure. Some toxins also have an accumulative affect when entering the body. To reduce the risk, either the length of exposure to the contaminant or the likelihood of exposure should be reduced. To eliminate the contaminant in its entirety is always preferable and should be considered as a priority. However in many cases some trace will remain.
Hazardous materials that may be present
The following are some of the more commonly found hazardous substances that may be present in historical artefacts.
Pesticides, fumigants and preservatives. Many collections have been treated to prevent pest infestation, fungal damage or to prevent decay. A wide range of highly toxic substances like DDT, arsenic, cyanide and mercury compounds were used in the past on textiles, furs, feathers and ethnographic objects. Residues can still remain in trace or in air pockets, hence it is always safer to presume that articles have been treated with toxic substances and take appropriate actions when handling them as often no records are present of past treatment.
Asbestos. This is a naturally occurring fibrous mineral that is highly friable and, when breathed in, can cause various cancers. Apart from the raw mineral itself that could be displayed for learning purposes, asbestos has excellent fire retarding and heat insulating properties that used to be much sought after. To date, more than 3000 products that contain asbestos material have been identified, ranging from pure asbestos textiles to electrical products.
Cellulose nitrate (nitrocellulose). Used in early plastics and early films (photographic, motion picture and X-ray), cellulose nitrate is very unstable. It is highly flammable and may combust spontaneously releasing toxic gases.
Explosive ordnance. Stringent legislation covers the keeping of firearms, explosives and live ammunitions. It is best to have them disarmed and disabled.
Biological hazards. Old, soiled medical equipment could harbour traces of body fluids carrying biological pathogens like smallpox. The same is true of artwork where human blood, hair, bone or urine was used. With animal products, anthrax spores could be present (dormant until breathed in). Tetanus is also a possibility if employees are scratched or punctured with sharp, contaminated objects.
Radioactive material. Apart from mineral items that could be naturally radioactive (ie contain tiny amounts of uranium or thorium), luminous radium paint was historically used in watches, clocks and instrumental dials. Even if they no longer glow, they are still radioactive so care needs to be taken when flaking occurs due to deterioration.
Lead. Metal lead and all its compounds have a cumulative effect on the body. Lead was used in all sort of items, eg paints, pigments, ceramic glazes, lead toys and weights. As it corrodes, a powdery substance forms that can easily become airborne. Breathing this lead dust over time could cause lead poisoning.
Moulds. Many collections, when exposed to very humid atmospheres, develop mould, which can cause health problems when inhaled. Mould spores are present everywhere and will become active where darkness, stagnant air, elevated temperatures and a source of moisture creates the ideal environmental conditions.
Natural poisons. Various natural poisons may be present within clothing, toys and jewellery, where poisonous seeds were used as decorations. Spears, arrowheads and knives used by native people also could have been dipped in poisons for hunting.
Management actions to control exposure
Artefacts do require vigilance and attention to safety when handled. Knowledge is always the best defence against potential risks. Take precautions and treat all articles as hazardous if unsure. Other safety management actions that should be taken include the following.
Carry out an inventory of what items have the potential to cause harm. If in doubt seek expert advice.
Maintain Material Safety Data Sheets (MSDS) of known contaminants to address appropriate actions needed.
Practice safe storage, labelling and handling procedures dependant on the risk identified and carry out inspections in well-ventilated areas.
Ensure good housekeeping and keep all work areas clean and free of any possible contaminants, disposing of hazardous materials properly.
Maintain good hygiene and cover up any broken skin. Warn employees not to touch their face when handling artefacts and provide appropriate personal protective equipment.
Anyone that is likely to handle hazardous artefacts needs to be adequately trained and competent for the tasks they undertake.
As an additional measure, employers should consider personal exposure monitoring when dealing with known hazards. This will help in evaluating if likely exposures are within occupational exposure limits, and can assist with creating accurate risk registers and management safety procedures.