Platelet Aggregation Induced By Formaldehyde
Thrombosis and Haemostasis
Formaldehyde causes platelet aggregation (or agglutination) which varies with dosage. Aggregation was studied in ten blood samples drawn from normal volunteers. A small volume of formaldehyde was added to platelet rich plasma in a light transmission aggregcmeter to produce final formaldehyde concentrations between 0.1% and 8%. Measurements were made by three methods: (1) light transmission aggregometry, (2) visual semi-quantitative microscopic analysis, and (3) quantitative image analysis
... mage analysis (Computerized Platelet Aggregation Analysis) . Using the visual semi-quantitative microscopic method, the dose response curve (expressed as the percentage of platelets involved in aggregates) increased from 11% at a formaldehyde concentration of 0.1% to 41% at a 0.5% formaldehyde concentration; it then decreased to 11% at a formaldehyde concentration of 8%. This curve may reflect the influence of two different formaldehyde effects: an aggregating effect which increases until about 0.5% concentration, whereafter a fixative effect may predominate. Light transmission aggregometry recordings did not provide a reliable indicator of the presence and degree of aggregation. A comparison of the visual semi-quantitative method and CPAA show similar detection of aggregating effects. In sunmary, formaldehyde has an aggregating effect on normal platelets. The physiologic significance of this effect is unknown; however, because formaldehyde is used to process platelets in studies of platelet aggregation, this effect may be of importance.