PM 2.5 refers to the particulate matter that has diameter less than 2.5 micrometers and remains suspended in the air for a longer period of time and their short-term exposure can cause health effects such as eye, nose , throat and lung inflammation, coughing, sneezing, runny nose and shortness of breath. George Mason studied the exposure of harmful air pollutants such as PM2.5 emitted by traffic during rush hours and relates them to the adverse health consequences, including preterm birth and low birthweight and the study was published by Dr. Jenna Krall in a reputed journal. In order to assess women's exposure to small particulate matter air quality (PM2.5), Krall and colleagues performed the studies to use personal air pollution monitors with traffic controls. Among their survey of 46 women with an average age of 26 commuting in Washington , D.C., they gathered data over a 48-hour period.
Their research elaborated that compared to men, women have different commute or travel habits, for example because of increased trips for household grocery shopping and carrying infants, therefore the women have different patterns for the exposure of air pollutants. Longer exposure to the traffic PM 2.5 would definitely increase the health risks. Their study contributes to the relationship of the exposure of women not having a trip to the extensively rush areas to the trips that were performed to the traffic crowded areas in rush hours. They did not noticed variations in PM2.5 exposures depending on trip length, which does not indicate variables that affect exposures, such as traffic volume. Therefore higher traffic volume may contribute to the higher pollution levels so the exposure will be swear in these conditions.
It was concluded from their research that during rush hours the PM2.5 concentrations were higher during vehicle trips as compared to the exposures during not having the trips. While individual traffic PM2.5 pollutants, such as zinc PM2.5, were positively associated with rush hour PM2.5, such as if the exposure during the rush hours if higher the pollution intake would also be higher and the probability of getting adverse effects is higher.Furthermore in the future work it was recommended to record the individual exposure constituents and their threat, along with the travel time, the other features such as travel speed and traffic volume should also be kept under consideration.