What are the blood routine findings associated with excessive formaldehyde exposure?

Under normal circumstances, formaldehyde is a chemical substance with irritant properties. When present at excessive levels, it may affect the human blood system. Blood test abnormalities primarily include abnormal white blood cell count, changes in the red blood cell system, fluctuating platelet counts, altered lymphocyte ratio, and neutrophil abnormalities. The detailed analysis is as follows:

1. Abnormal White Blood Cell Count: Formaldehyde may suppress bone marrow hematopoietic function, leading to decreased white blood cell count below the normal reference range. White blood cells are crucial immune cells; a reduced count weakens the body's resistance, making it more susceptible to pathogens such as bacteria and viruses, thereby increasing the risk of infection.

2. Changes in the Red Blood Cell System: Long-term exposure to environments with excessive formaldehyde levels may impair red blood cell production, resulting in decreased red blood cell count or hemoglobin concentration, leading to mild anemia-related findings on routine blood tests. In such cases, parameters like mean corpuscular volume (MCV) and mean hemoglobin content may remain normal, but slight abnormalities can occur if utilization of hematopoietic nutrients is affected.

3. Fluctuating Platelet Count: Formaldehyde may damage megakaryocytes in the bone marrow, affecting platelet production and causing a reduction in platelet count. Platelets play a key role in the coagulation process; a lower count impairs clotting function, and blood tests may show platelet levels below the normal lower limit.

4. Altered Lymphocyte Ratio: Lymphocytes are a major component of white blood cells. Excessive formaldehyde exposure may impact the immune system, causing abnormal lymphocyte ratios. In some individuals, this manifests as a decreased lymphocyte percentage, indicating suppressed immune function.

5. Neutrophil Abnormalities: Neutrophils are critical for defending against bacterial infections. Elevated formaldehyde levels may interfere with neutrophil production or function, leading to changes in neutrophil count or proportion. Most commonly, neutrophil counts decrease, reducing the body’s ability to resist bacterial infections.

It is recommended that individuals avoid prolonged exposure to environments with excessive formaldehyde. Newly renovated spaces should be adequately ventilated to dissipate odors before occupancy. Activated carbon filters and air purifiers can also be used to help reduce formaldehyde concentrations.