Lead Test

The test is used to evaluate the concentration of lead in your blood to determine if you have been exposed to harmful levels.

Blood lead concentration is monitored in workers whose environment contains lead.In the UK the main sources of lead exposure are air-borne lead (from industrial sources and from the use of lead in petrol), water-borne lead (where lead dissolves readily from lead piping or from lead solder in water pipes, sometimes found in pre-1970s buildings), and occupational and hobby exposure (e.g. plumbers and stained glass artists).

For screening: Blood tests may be requested to screen people in the workplace if lead contamination is a potential problem. This testing conforms to Health and Safety Executive rules for occupational exposure. 
Adults who work in industries known for lead exposure, for example plumbers, lead miners, shipbuilders, construction workers, demolition workers and pottery manufacturers should be screened for lead exposure. Adults who have hobbies that involve lead-based paints, ceramics, soldering etc should also be tested. For a list of hobbies that may expose you to potentially high levels of lead, go to lead poisoning. 
The Health and Safety Executive (HSE) has developed rules for monitoring for lead in the workplace: In general, if a worker has a blood lead concentration of 2.4 µmol/L (50 µg/dL) or higher, then their employer is required by law to try to reduce exposure. If a concentration of 3 µmol/L (60 µg/dL) or higher is found then the worker may have to be suspended from work. 

For diagnosis: The test can help determine whether symptoms, including fatigue, stomach pains, changes in mood, nausea, headache, tremors, weight loss or decreased libido are due to lead poisoning. The test may also be needed if a patient has peripheral neuropathy, anaemia, reproductive failure, encephalopathy, or memory loss, which are symptoms of lead poisoning. In children the symptoms of chronic lead poisoning are slightly different and they are more likely to present with, for example, developmental delay.

The higher the test result, the more lead is in your system and the more potential danger there is to your health. However the amount of lead in the blood does not reflect the total amount of lead in the body. This will depend on how long a person has been exposed to elevated lead levels. 

Guidelines and recommendations for treatment differ for children and adults. Most experts agree that at a very high blood lead concentration, above 3.5 - 4 µmol/L (72.5 - 83µg/dL), a person is at the medical emergency level and should get immediate medical attention. Chelation will be considered in all patients with blood lead concentrations >2.4 umol/L (50 ug/dL).  Abatement - removing the source of the environmental exposure to lead - must also be done. Most also agree that adults with blood concentrations of less than 0.48 µmol/L (10 µg/dL) are not lead poisoned, and further testing is not necessary unless they are exposed again. Children are more susceptible to lead poisoning than adults and so in children blood lead concentrations should not exceed 0.24 µmol/L (5 µg/dL). Any child who has an elevated blood lead concentration needs to have their home or other environment evaluated and their blood lead levels monitored to ensure no further exposure. Other people at the residence should be tested as well. Without treatment or abatement of the environmental cause, the elevated lead level will likely recur. 

Poisoning with lead is more harmful for children, whose brains and other organs are still developing. Adults tend to recover from lead ingestion better than children. If you think your children may be at risk, have them tested as soon as possible.

Iron deficiency can make lead easier to absorb in the body. Children with raised blood lead concentrations should be tested for iron deficiency.

Each person handles lead differently. What may be toxic to one adult may not be toxic to another. Thus, laboratory tests are just one part of the picture in lead poisoning cases. Careful monitoring with medical examinations are needed.

Apart from the sources of lead discussed above, recent cases of exposure have been from imported products such as cosmetics and household items and toys painted with lead paint.

Products that still contain lead include batteries, solder, some pipes, ammunition, roofing, industrial paints, and X-ray shield materials.