Does this test have other names?
Protoporphyrin, ZPP, zinc protoporphyrin test, erythrocyte protoporphyrin test
What is this test?
The protoporphyrin test is used to diagnose blood problems caused by lead. The test
can show lead exposure or lead poisoning. Lead poisoning is extremely dangerous because
lead can damage organs throughout the body.
Lead poisoning does not always cause symptoms, so a blood test may be the only way
to confirm lead exposure or poisoning. (Healthcare providers usually order a protoporphyrin
test after a simple blood screening shows higher levels of lead.) The test can also
find an iron deficiency anemia or other types of anemia.
The protoporphyrin test doesn't measure the levels of lead in the blood. Instead it
measures how the blood has been affected by lead. Lead can harm the blood's ability
to make new blood cells. The protoporphyrin test measures the effects of lead exposure
that have happened over the past 2 to 3 months.
Why do I need this test?
You may need this test if you have signs and symptoms of iron deficiency or lead poisoning.
Repeated miscarriages or fertility problems
Digestive problems, such as nausea, vomiting, or constipation
High blood pressure
Metallic taste in the mouth
You may need this test if the result from your blood lead screening is 25 micrograms
per deciliter (mcg/dL) or higher. Children may have the protoporphyrin test to confirm
lead poisoning, but other tests are used for screening or diagnosing lead poisoning
in children. You may need this test if you have been exposed to lead or if your healthcare
provider suspects that you have lead poisoning or an iron deficiency. It is important
to find out if you have toxic levels of lead in your body, because the complications
can be permanent.
What other tests might I have along with this test?
You may need a number of other tests along with a protoporphyrin test, including:
Complete blood count
Blood erythrocyte protoporphyrin test
Reticulocyte count, or a count of young red blood cells
Serum iron, iron binding capacity, ferritin levels, or other measurements of iron
in the blood
What do my test results mean?
Test results may vary depending on your age, gender, health history, the method used
for the test, and other things. Your test results may not mean you have a problem.
Ask your healthcare provider what your test results mean for you.
Test results showing zinc protoporphyrin levels higher than 35 mcg/dL mean that you
have a high level of lead in your blood.
How is this test done?
The test is done with a blood sample. A needle is used to draw blood from a vein in
your arm or hand.
Does this test pose any risks?
Having a blood test with a needle carries some risks. These include bleeding, infection,
bruising, and feeling lightheaded. When the needle pricks your arm or hand, you may
feel a slight sting or pain. Afterward, the site may be sore.
What might affect my test results?
Only exposure to lead should affect your test results. If a fingerstick method is
used, contamination of your fingertip can affect the results. If you have a positive
result, it should be confirmed before you start treatment.
How do I get ready for this test?
A blood test rarely needs any preparation. You can probably eat, drink, and take your
medicine as usual, but check with your healthcare provider. Be sure your healthcare
provider knows about all medicines, herbs, vitamins, and supplements you are taking.
This includes medicines that don't need a prescription and any illicit drugs you may