Additional handling procedures for some documents

Image showing a respository at The National ArchivesLast year, we temporarily withdrew access to the record series, FCO 141 (Foreign and Commonwealth Office and predecessors: Records of Former Colonial Administrations: Migrated Archives) because we found evidence of historical preservation treatment. This indicated that insecticide had been used. External testing of the documents confirmed this, and following consultation and testing with occupational hygienists the risk to people was assessed as minimal and we returned the record series to the Reading Rooms with additional safe handling procedures in place.

Further documentary research into the historic use of insecticides on documents has identified some further record series which may have been treated with insecticides in the same way as FCO 141.

The record series affected can be found at this link

Using the knowledge we acquired last year, we are keeping the records available for ordering and viewing but with the same additional handling procedures that are used for FCO 141.

When viewing any of the records from the series above, please follow the handling procedures below: –

  • Records will be viewed in a separate room within the main Reading Room and must be ordered in advance to ensure you are allocated a seat on the day you wish to visit.
  • We will provide disposable Nitrile Gloves for you to wear while using the documents.
  • If you are using mobile phones, cameras, laptops, and any other objects while viewing the documents, they must be wiped down with the materials provided prior to leaving the Reading Room or after handling the documents.
  • Please refrain from touching your face, eyes or mouth whilst viewing the records, and wash your hands thoroughly with soap once finished.

If you have any questions, please speak to staff in the Reading Room. All other Reading Room rules should be followed.


Frequently Asked Questions Regarding Additional Records 

  1. Are any other record series likely to have been treated in the same way?

As part of our continuing care and preservation of the collection we are now aware of the need for further testing of our collection for the potential presence of pesticides as a result of historic preservation treatments. We have identified other record series that were potentially created and initially stored in similar environments to FCO 141.

It is possible that other items from the late nineteenth century to the 1970s may have been treated to prevent documents being destroyed by insects. We are aware that in some parts of the world these types of preservation techniques may have been more prevalent. However, pesticides and insecticides have been used all around the world to prevent collections from being damaged by insects and mould. Historic records indicate that many libraries and archives were applying a variety of insecticides to their storage spaces in the past. Whether contaminants persist on other items, and at concentrations high enough to cause concern, is a topic that requires further research. It is therefore important that readers always follow proper hygiene when handling documents: avoid touching the face and wash hands before and after handling of items, especially before consuming food or liquids.

  1. Are the other records likely to be withdrawn from the Reading Room?

Colleagues are working to understand the potential presence of historic pesticides in further records within The National Archives. Last year when we tested the FCO 141 series, we consulted with occupational hygienists to assess the level of risk and to advise us of safe handling guidelines.

With appropriate measures in place, we returned the record series to the Reading Rooms. Working under these guidelines, the newly identified records will remain in the Reading Rooms and the public will be able to order and view them with certain additional guidelines in place i.e., looking at the documents wearing gloves provided by TNA and washing hands upon completion of their viewing. As a result of the need for additional handling measures, the series will be advance order only. We will keep the public updated and advise of any further changes.

  1. Should I be worried – I have looked at some of these new records?

From our testing of FCO 141, we know that the risk to health was and remains minimal, assuming that readers have been following our Reading Room handling guidance.

  1. Are you going to test again?

Currently TNA is working with collection experts to understand the potential presence of historic pesticides in further records within The National Archives. It is possible that we will carry out further tests on these newly identified documents. The health and safety of our visitors and staff is a priority for us and we want to understand the processes documents have gone through prior to being transferred to TNA.

Frequently Asked Questions regarding records series FCO 141

  1. Why did you withdraw the record series FCO 141?

In 2022 while working with the records, staff observed that some documents had stickers stating that insecticides had been used in the binding of the documents. The whole series was temporarily withdrawn while we investigated if insecticides remained on the documents.

  1. What did the tests entail?

The tests were carried out in two ways – non-invasive/non-destructive testing by X-ray fluorescence spectroscopy to detect heavy metals (mercury, lead, arsenic), and invasive/destructive testing using Gas Chromatography-Mass Spectroscopy to detect and identify organic insecticides (DDT, Lindane, dieldrin, and similar).

  1. What did the tests show?

The results indicated that the items were contaminated with historic organic pesticides (DDT, Lindane, dieldrin, pentachlorophenol, and 1-chloronaphthalene). The glue of several items also tested positive for mercury.

  1. What do these results mean for readers and those handling the documents?

We allow access to records in the FCO 141 series but there are certain safety protocols to observe. You must wear gloves when looking at records from FCO 141. This is to protect you from any transfer of historic pesticides to your skin. Our guidance, stating that gloves are not required when looking at all other documents, remains in place.

  1. I’ve handled the documents, should I be worried?

The tests we carried out to identify the insecticides and to understand the risk to people handling the items indicated that the acute risk to health is minimal, assuming that readers have been following our Reading Room handling guidance.

  1. Where did the insecticides come from?

Records indicate that insecticides were applied as a preservation method by bookbinders, staff, archives, and libraries historically. The insecticides were either directly sprayed on shelves and items or incorporated into the binding glue used to attach the covers to bound books, notebooks, and ledgers, to prevent insects from feeding on the paper. Some, though not all of the items in FCO141 contain stickers or stamps indicating treatment.