Table 2.

Increased detection of endotoxin activity in barn and house dust following pre-treatment with Tris/EDTA.

Organic Dust	Pretreatment	EU/mg dust*	Fold Increase (P-value)
Barn Dust	Pyrogen-free water	305 ± 10
	Tris/EDTA	1701 ± 83	5.6 (<0.001)
House Dust	Pyrogen-free water	73 ± 5
	Tris/EDTA	228 ± 11	3.1 (<0.001)

^*Several aliquots (50 mg each) of a single collection of barn dust and of house dust were dispersed and extracted in 1 ml of PFW or Tris/EDTA, as indicated. Each of the recovered supernatants was tested by the LAL assay for endotoxin and expressed as EU/mg of dust.

Results represent the mean ± SEM of at least ten separate determinations.