where Y is the response (in terms of % end–expiratory flow rates),
X is dose rates (ʅg/kg) for children estimated from the corresͲ
ponding values given for NO2 in Neuberger et al. (2002). The dose
value at which end–exspiratory flow rate becomes lower than
100% was taken as the LOAEL value for NO2 (Pandey et al., 2005).
Thus, the health risks have been defined by the following
equation (Pandey et al., 2005; Kalaiarasan et al., 2009; Castro et
al., 2011; Zhao et al., 2011):