Quantity of Bet v 1 (Q) inducing a conjunctival response
As the allergen affected the ocular surface, we used the tear film renewal rate (TRR) to estimate the amount of extract applied during EEC exposure. The TRR was calculated to be 154×106mm3/min by Beaudouin et al.18 Thus, the quantity (Q) of extract applied was calculated in nanograms as follows: Q = C x Time x TRR, where C is the concentration of airborne Bet v 1 in ng/m3 and Time is the time required to induce the conjunctival response in minutes.