The Zinc Protoporphyrin (ZPP) test contains 1 test with 1 biomarker.
Description: The Zinc Protoporphyrin test is a blood test that measures levels of zinc protoporphyrin in your blood to screen for lead exposure and iron deficiency anemia.
Also Known As: ZP Test, ZPP Test, Free Erythrocyte Protoporphyrin Test, FEP Test
Collection Method: Blood Draw
Specimen Type: Whole Blood
Test Preparation: No preparation required
When is a Zinc Protoporphyrin test ordered?
When long term exposure to lead is known or suspected, ZPP may be done in addition to a lead test.
When an individual participates in a program for occupational lead monitoring or when they regularly come into contact with lead through a pastime, such as working with stained glass, the test may be required.
ZPP may be requested when there is a suspicion of iron insufficiency in children or adolescents or as a screening test for the condition.
What does a Zinc Protoporphyrin blood test check for?
Small levels of zinc protoporphyrin are typically found in red blood cells, although the level may rise in lead poisoning and iron shortage patients. The ZPP level in the blood is determined by this test.
It is first required to understand heme in order to comprehend how lead poisoning and iron deficiencies impact the ZPP level. The protein hemoglobin, which is found in red blood cells and delivers oxygen from the lungs to the body's tissues and cells, must have heme as one of its constituent parts.
An iron atom is inserted into the core of a molecule known as protoporphyrin to complete the process of heme synthesis. When zinc is present, as in lead poisoning, or when iron cannot be inserted into the body, as in iron shortage, protoporphyrin combines with zinc to create zinc protoporphyrin. Since ZPP cannot bind to oxygen, it has no functional function in red blood cells.
Lab tests often ordered with a Zinc Protoporphyrin test:
- Iron Total
- Iron and Total Iron Binding Capacity
- Ferritin
- Hemoglobin
- Hematocrit
- Complete Blood Count (CBC)
Conditions where a Zinc Protoporphyrin test is recommended:
- Lead poisoning
- Iron Deficiency Anemia
How does my health care provider use a Zinc Protoporphyrin test?
Iron deficiency in children and chronic lead poisoning in adults are the two main conditions for which zinc protoporphyrin is prescribed.
Red blood cells often contain modest levels of the chemical ZPP. The majority of the protoporphyrin in red blood cells interacts with iron to create heme, which is the oxygen-carrying molecule in hemoglobin. When there is not enough iron available to produce heme, as in iron deficiency, or when lead is present and prevents the synthesis of heme, as in lead poisoning, zinc joins with protoporphyrin instead of iron. With these conditions, the blood's ZPP concentration will increase.
To test for chronic lead exposure, ZPP testing may be requested in addition to a lead level. People who reside in older homes and hobbyists who work with materials containing lead may be more susceptible to contracting lead poisoning. Lead levels may be enhanced in those who inhale lead-containing dust, touch lead directly, contaminate their hands, and then eat. Lead and ZPP levels in children who eat lead-containing paint chips may be raised.
The Occupational Safety & Health Administration highly advises that a ZPP test be done each time a lead level is requested in an industrial setting in order to monitor an employee's exposure to lead. Both are required since ZPP does not alter fast when a person's source of lead exposure is eliminated and it does not represent recent or acute lead exposure. ZPP is most effective at determining a person's average lead exposure over the previous 3–4 months.
As readings do not increase until lead concentrations are over the permissible threshold, ZPP is not sensitive enough to be used as a lead screening test in children. The Centers for Disease Control and Prevention have established a very low level as the maximum lead concentration deemed acceptable for children. To identify lead exposure in this age range, tests that assess the blood lead levels are performed.
The ZPP test may be requested in order to detect iron insufficiency in children at an early stage. Most young people will have elevated ZPP levels prior to showing any signs or symptoms of anemia, which is one of the early indicators of inadequate iron storage. To confirm iron insufficiency, more detailed testing of iron status are needed.
What do my Zinc Protoporphyrin test results mean?
Typically, there is very little ZPP in the blood. The cause of a disruption in heme production can be inferred from an increase in ZPP, but the explanation is not always clear. Iron deficiency and lead poisoning are the main causes of increases in ZPP.
It's crucial to consider a person's history, clinical observations, and the outcomes of additional tests including ferritin, lead, and a complete blood count when evaluating ZPP levels. The patient may suffer from both lead toxicity and iron deficiencies.
ZPP represents the average lead level over the past three to four months in situations of chronic lead exposure. A ZPP test, however, cannot identify the quantity of lead that is now present in the blood as well as the amount that is present in the organs and bones. Following exposure, ZPP values increase more gradually than blood lead concentrations, and they take longer to decline once lead exposure has ended.
The most frequent cause of an increase in ZPP in children is iron insufficiency. Following iron supplementation, a declining ZPP value over time certainly suggests a successful course of treatment.
We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results.
