Pest Control Fact Sheets

Psocid's or Booklice or Dustlice

Facts about psocid's

Psocids are common but harmless household pests
They can live in dry powdery type foods such as flour, sugar and semolina and can also be found in old books, carpets and other furnishings in the home (which is why they are sometime called book or dust lice)
They feed on moulds and mildews
They are not caused by poor hygiene - they are just as common in the cleanest of homes
Research has shown that the sort of psocids found in homes are rarely found where food is produced, so they are unlikely to be brought in to the home in foods

How can you identify a psocid?

See image of psocid shown at the top of the fact sheet
Smaller than a pin head
Have soft bodies which are white/ light grey/ light brown or even black in colour
6 legs
No wings
Long, developed antennae

What causes them?

It is certain that they are associated with high humidity. This could be caused by new plaster drying out, or could be due to condensation from not having enough ventilation in the kitchen. There are many reasons but you can be sure that if you have psocids, you have humid conditions.

The kitchen is likely to provide the conditions they need, and fitted cupboards provide the darkness, which attracts them. With ideal conditions they can rapidly increase in number.

In large numbers they can spread bacteria from one area to another. This can result in food and surface contamination.

Prevention and treatment

Try to deny the conditions they need to survive and multiply
Always keep your dry foodstuffs and cereals in a cool, dry, well ventilated place
Clean out your cupboards regularly. If you use water, always make sure you cupboards are completely dry before you put the food back
When you are cooking, boiling the kettle or using the tumble drier, make sure the kitchen is properly ventilated. If condensation shows on windows it is being produced on all other surfaces as well, leading to mould growth on which psocids thrive
Remove infested food and dispose of outside
Treat the affected area with a good household insecticide, which is suitable for use near food
Find the cause of humidity and cure it

Please follow the instructions on pesticide containers carefully.

Service we provide

We offer a free identification service. You will need to catch the insect, seal it securely in a clear plastic container labelled with your name, address and telephone number. You can contact us for a suitable container.

You should then send it us by post at the address shown below or you can take it to one of the following offices:

Barking Office: Barking Learning Centre, 2 Town Square, Barking, IG11 7NB|

Dagenham Office: Housing Enquiries Office, 2 Stour Road, Dagenham, RM10 7JF|

Our qualified pest officers will identify it and let you know what it is. Our pest control team do not deal with Psocids as they very rarely cause nuisance but we can provide advice on how to deal with reoccurring infestations.