Measurement of Horse Allergen (Equ cx) in Schools

Table 1

Horse allergen levels in classrooms from Study I and II, sampled with Petri dishes.

	Study I	Study II
Sampling year	1997/1998	2003
Analysis year (enhanced ELISA assay)	2005	2009
Median horse contact among students	9%	12%
No. of samples	293	97
Samples < dl	74%	29%
GM U/m^2/day (Total)	8.4	20.8
GM U/m^2/day (in classes above median rate of horse contact)	10.5	32.6
GM U/m^2/day (in classes below median rate of horse contact)	6.3	13.2