This project involves collecting dried blood spots and urine
samples as possible alternatives to venous blood samples for
determining workplace exposure to lead and cadmium. Typically
blood samples are taken to ensure that workers are not being
exposed to cadmium and lead in the workplace. We would like
to try looking at whether we can get the same information from a
finger pricked blood spot. We would also like to see whether
urine samples can be used in some instances. This study will
look at both.
What samples are required?
This study will collect a venous blood sample (as your normal
workplace biological monitoring sample), a urine sample and a dried
blood sample.
What is a dried blood spot?
This is a small amount of blood (10µL) drawn from your clean
finger tip and placed on a collection device. This blood is
then deposited on a filter paper. The blood dries on this
filter paper.
How do we collect the samples?
Dried blood spot
As shown above, you use a lance at the side of the finger to
puncture the finger. The finger is then squeezed a little and
the first drop is wiped away. The next drop of blood is
placed on the sampler hole of the collection device. We
require two spots so this is repeated.
Venous sample
This will collected with a needle and sample bottle as
normal.
Urine sample
This will be collected (in a 25 ml sterilin tube) around the
same time as the blood samples.
All samples will be posted to the laboratory for analysis.
What will we do with the samples?
We will analyse the samples for lead and/or cadmium depending on
your workplace exposure. You will receive the venous blood sample
result as normal. However the dried blood spots and urine results
will be reported in a summary of all the project results and shared
with you.
Why is it important to measure exposure to lead and
cadmium?
The quick answer is to help reduce workplace exposures. Lead and
cadmium are associated with a number of ill-health related outcomes
and so it is necessary to keep your exposure low. By
measuring lead and cadmium in your blood you will know what your
overall exposure is.
When high levels occur it may be advised to review your
workplace controls such as extraction systems, wearing personal
protective equipment or improving the overall cleanliness of the
workplace.
Will you help?
HSE scientists are trying to develop less invasive methods for
sampling. We need volunteers to provide a venous blood
sample, a urine sample and two dried blood spot samples.
What will it involve?
HSE scientists will not visit your site, instead the person
normally responsible for taking the blood sample will oversee the
collection of the dried blood spot and urine samples.
What will the result mean?
The results will tell us if by measuring lead and cadmium on
dried blood spots whether they give the same result as those from
venous blood samples. If they give similar results then they
would be an easier method for collecting blood samples. It
may be possible to undertake dried blood spot samples in future
instead of venous samples.
The urine samples will allow us to see whether there are any
workplace exposures where it would be satisfactory to collect a
urine sample.
If you would like to discuss further or be involved, please
contact Dr
Jackie Morton.