The Effects of Environmental Parameters on Air Sampling with SPME from Halogenated Hydrocarbons

As environmental parameters may affect the precision of the real amounts of analytes absorbed by solid phase micro-extraction therefore in this study the effects of humidity, temperature and wind velocity on air sampling rate from some halogenated hydrocarbons were investigated. Also, different conditions for sample storage are tested. In this cross-sectional study, a dynamic system was built in the laboratory for atmosphere generation. The configuration of the chamber was suitable for sampling at various environmental parameters. Carboxen/polydimethylsiloxane (CAR/PDMS) was selected for sampling and the samples were analyzed by GC-MS. The results showed no significant difference for ± 5°C temperature variation in the range of 20 to 30°C (P value > 0.05). Data analysis revealed that increased humidity has a significant negative effect on the sampling rate. Our data showed no significant difference with retracted SPME at different air velocities in the chamber (P > 0.05). The effect of storage time and conditions on the mass recovery at different condition showed that halogenated hydrocarbons were lost after three days in ambient temperature. It is concluded that the relative humidity must be considered during sampling and samples can be stored for three days in sealed septum-capped glass tubes in the refrigerator.