We are measuring the personal exposure to nitrogen dioxide!

In the BiSC project a precise evaluation of the main air pollutants to which the participant is exposed is carried out.

Among these pollutants we find nitrogen dioxide, which is one of the most related to road traffic. Nitrogen dioxide measuring equipment is small plastic tubes with two caps at their ends (one gray and one white). In the gray plug, there is a metal mesh impregnated with a reagent that absorbs nitrogen dioxide. To start the measurement, the white cap of the tube is removed and through the process of molecular diffusion, the air circulates from the outside (high concentration of the contaminant) to the inside of the tube (low concentration of the contaminant) where it is absorbed. 

Metal mesh on the gray cap.

Example of tube installed outside, together with the sound level meter.

Both in the environmental visit of the beginning of pregnancy, and in the third trimester, 3 tubes are installed to measure this compound. These tubes will be exposed to the ambient air for a week: one outside the house, another inside (in the participant’s room) and the staff (the participant will take it with her for a week).

Finally, the concentration of nitrogen dioxide to which it has been exposed is determined by laboratory analysis.

And in this way, in the BiSC project we are able to determine the personal exposure to nitrogen dioxide for different periods of time to be able to subsequently carry out longitudinal studies and see its relationship with the development of the baby.

The text was written by Beatriz Jurado, a fieldworker from the BiSC project.