Arsenic

Arsenic occurs naturally in the minerals skutterudite and arsenic pyrite, both of which may be held in geological collections.

It also has a myriad of applications, featuring in products as diverse as batteries, pesticides, medicine, fabric dyes, and poultry feed!

Fashion items from Victorian times often used dyes that contained significant amounts of arsenic, such as Paris Green, Scheele’s Green, and London Purple.

Prior to the 1980s, museum staff frequently preserved natural history, ethnographic, and textile collections by spraying them with arsenic-based pesticides because the heavy metal's toxicity deterred insects and other pests from damaging the items. Mercury and lead were also used for this reason.

Arsenic is very toxic and can affect people when they are exposed to small doses over a long period of time, or larger doses over a short period of time.

People suffering from arsenic poisoning will present with a range of symptoms, so it can be difficult to diagnose.

The use of a hand-held portable x-ray fluorescence (pXRF) analyser is a great way of testing your items for arsenic and other heavy metals without risk of damage. There are other chemical spot/wipe tests that can also be undertaken.

If your institution is situated in Otago or Southland and you think there is arsenic in your collection, Tūhura Otago Museum would be happy to help investigate. We are lucky enough to have a Bruker Tracer pXRF which we use on a regular basis.

Ensure your institution’s health and safety plan includes the following points:

• Identifying and labelling arsenic-containing items. This should include items you suspect of containing arsenic but haven’t confirmed.
• Assess the risks from your arsenic-containing exhibits
• Have processes for accidents, incidents, emergencies, and disposal concerning any arsenic-containing items
• Document staff training and keep secure medical records

You can learn more about health and safety plans by going to Health & Safety

Once you have identified and assessed any risks, you mitigate them. You can ensure that the public are unable to handle any taxidermy, fabrics, or other collection items that are known to contain arsenic or other heavy metals.

Keep an inventory of your items that contain, or are suspected to contain, arsenic and other heavy metals so that staff are aware of which items are potentially hazardous and know how to handle the items.

If staff are going to be regularly handling items that contain arsenic, you may wish to medically monitor arsenic levels in your staff. You will have to seek the advice of a GP specialising in occupational medicine to arrange this.

If you wish to dispose of any heavy metal items, contact a WorkSafe-accredited company (see https://register.hasanz.org.nz ), or if you wish to discuss your options further, please feel free to contact the Collections team at Tūhura Otago Museum.

This is a possible plan of action if you are going to test and/or move a number of arsenic-containing items:

• Test staff and a control group for baseline levels
• Set up a space to test the items and record the results
• Ensure that you have the correct PPE for the staff doing the testing
• Record and test (note whereabouts on the item you have tested)
• Once you have the test results, label the exhibit accordingly
• Write procedures for storing, handling, and displaying exhibits
• Retest staff after testing/recording is complete

Plan ahead:

• Consider what to do with exhibits that test strongly positive
• Consider where to store staff medical records
• Consider what actions to take if staff show elevated heavy metal levels

• WorkSafe encourages PCBUs to use the services of consultants who are listed on the HASANZ Register: https://www.hasanz.org.nz/hasanz-register-for-businesses/

• Workplace Exposure Standards