Survey on Formaldehyde Dispersion in Zarghan, Iran, Using Passive Sampling and Geographic Information System Software

The aim of this study was the determination of formaldehyde dispersion pattern in Zarghan, Iran, through passive sampling and using geographic information system (GIS) software.
In this cross-sectional study, passive sampling method was used to measure the concentration of formaldehyde at 10 stations. Sampling was conducted in one season for the duration of 14 days. Formaldehyde concentration in other areas of the city was interpolated in ArcGIS software using nearest neighbor (NN), inverse distance weighting (IDW), and Kriging methods.
Findings: The results showed that formaldehyde concentration near Fars Chemical Industries Co. (FCICo.) and Sina Chemical Industries Co. (SCIC) was 38.1 μgm-3. Interpolation using GIS showed that the concentration of this pollutant, based on the direction of the wind, at a distance of 1400 m from the source was at the standard limit of 10 μgm-3.
NN interpolation was the most suitable method for determination of formaldehyde concentration. During morning inversion and when the weather is in stable conditions, the concentration of formaldehyde around the chemical industry was several times higher than the average limit. In spite of the mountains surrounding the city, formaldehyde concentration in residential areas of Zarghan and Dudag, Iran, was at the standard limit.