Biological monitoring in the workplace
Information for employees on its application to chemical
WHAT DOES YOUR EMPLOYER HAVE TO DO?
Many jobs involve using chemicals which can harm your health
if they are not properly handled. Under the Control of Substances
Hazardous to Health Regulations 1994 (COSHH) your employer has to
look for the risks to your health from chemicals in the
workplace. Your employer must make sure that your exposure to
chemicals is either prevented, or properly controlled. To do this
he or she may need to measure your amount of chemical exposure.
HOW CAN CHEMICALS ENTER YOUR BODY?
The main ways that chemicals can enter your body are:
- by breathing them in;
- by absorbing them through the skin; or
- by swallowing them. This can happen if your hands become
contaminated at work and you do not wash them before eating,
drinking or smoking.
If you are exposed to chemicals in the job you do, the most
common way of finding out how much you are exposed to is to
measure how much of the chemical is present in the air you
breathe in. However, this does not tell you how much of the
chemical has actually entered your body. In particular, it does
not measure how much has entered your body through the skin or by
swallowing. This is why we sometimes recommend biological
monitoring for certain chemicals.
HOW CAN THE AMOUNT OF CHEMICALS ABSORBED INTO YOUR BODY BE
Biological monitoring can be used to indicate how much of a
chemical has entered your body. It involves measuring the
chemical you are exposed to at work (or what it breaks down into)
in a sample of your breath, urine or blood. Which of these three
samples is used depends on how the chemical you are exposed to is
processed by your body. Biological monitoring is often used
together with air monitoring.
Biological monitoring is especially useful when:
- there is likely significant absorption through the skin;
- control of your exposure depends on personal protective
equipment and your employer needs to check it is protecting
WHY SHOULD YOU TAKE PART IN A BIOLOGICAL MONITORING
You do not have to take part in a biological monitoring
programme*. However, taking part is in your interests
because it shows you how much of the chemical you work with has
been absorbed by your body.
If your result is high it does not necessarily mean that you
will become ill, but it does indicate that your exposure may not
be properly controlled. Under these circumstances your employer
will probably need to look at how the chemical is being handled
to see how exposure can be reduced. To help assess the results
from biological monitoring, we publish Biological Monitoring
Guidance Values for some substances in the publication EH40
Occupational exposure limits (EH40/97 ISBN 0 7176 1315 1, this is
updated annually). * Under some circumstances, where
your employer is required under health and safety law to carry
out biological monitoring, there is an obligation on you to
co-operate. In particular, if you work with lead your
participation is required by the Control of Lead at Work
Regulations 1980 (to be replaced by new regulations in 1998).
HOW SHOULD YOUR RIGHTS AS AN INDIVIDUAL BE PROTECTED?
If you decide to take part in a biological monitoring
programme your employer needs to obtain your agreement before you
provide a sample. We recommend that this is done using a consent
form. The consent form is an agreement between you and your
employer to ensure that:
- you understand what the test results mean and what action
might be taken on the basis of them;
- you can decide who has access to your result (for example,
doctor, safety representative, health and safety manager);
- you can decide, for example, whether people see your
individual result or whether your result is anonymous and
pooled with other people's results;
- the sample you provide will only be analysed for the
chemical (or breakdown products of it) that you are exposed to
- the result of the test will not affect your conditions of
We recommend that your employer involves an occupational
doctor in the biological monitoring programme. As well as filling
out the consent form you may also wish to discuss with an
occupational doctor any risks that are associated with providing
the sample, and any concerns over the interpretation of your
HOW CAN YOU FIND OUT MORE?
If you have any concerns or questions about taking part in a
biological monitoring programme, you should raise them with your
employer, safety representative, union representative or the
person responsible for organising the biological monitoring
programme. More information about your employer's requirement
to control your exposure to chemicals which can harm your health
can be found in the COSHH Regulations 1994:
COSHH a brief guide to the Regulations: What you need to know about the Control of Substances Hazardous to Health Regulations 2002 (COSHH) Leaflet INDG136 HSE Books 2005 (single copy free or priced packs of 5 ISBN
9 7807 1766 4863) Web version: www.hse.gov.uk/pubns/indg136.htm
HSE publishes a more detailed guide
about biological monitoring Biological monitoring in the
Biological monitoring in the workplace: A guide to its practical application to chemical exposure HSG167 HSE Books 1997
ISBN 0 7176 1279 1
This leaflet is available in priced packs of 15 from HSE
Books, ISBN 0 7176 1450 6. Single free copies are also available
from HSE Books.
HSE priced and free publications are available by mail order from HSE Books, TSO Customer Services, PO Box 29, Norwich, NR3 1GN, Tel: +44 (0)333 202 5070 Website: https://books.hse.gov.uk/ (HSE priced publications are also available from bookshops and free leaflets can be downloaded from HSE's website: www.hse.gov.uk.)
Further advice can be obtained from HSE offices (see under
Health and Safety Executive in the telephone directory). For
write to HSE's Information Centre, Broad Lane, Sheffield S3
This document contains notes on good practice which are not compulsory but which you may find helpful in considering what you need to do.
This document is available at: www.hse.gov.uk/pubns/indg245.htm).
© Crown copyright This publication may be freely reproduced, except for advertising, endorsement or commercial purposes. First published 10/97. Please acknowledge the source as HSE.
Printed and published by the Health and Safety Executive
INDG245 10/97 C250
Added to the web Site 1/04/98