Table 3.

Exposure comparison with different hand washing practices.

a. Potential oral dose from different exposure protocols
	Median CFU (5%, 95%)
	No Washing	Control Bar	Antimicrobial #1	Antimicrobial #2
Transfer from Meat Preparation Surfaces
Cutting board-to-meat	1.9 × 103	3.5 × 102	5.9 × 101	9.0 × 101
(high dose)	(0.0 × 100, 9.7 × 104)	(0.0 × 100, 2.0 × 104)	(0.0 × 100, 3.8 × 103)	(0.0 × 100, 5.5 × 103)
Cutting board-to-meat	2.4 × 101	4.3 × 100	7.6 × 10−1	1.1 × 100
(low dose)	(5.7 × 10−1, 9.9 × 102)	(6.3 × 10−2, 2.1 × 102)	(2.9 × 10−4, 4.0 × 101)	(0.0 × 100, 6.0 × 101)
Knife-to-meat	5.8 × 103	1.0 × 103	1.8 × 102	2.6 × 102
(high dose)	(1.4 × 102, 2.4 × 105)	(1.6 × 101, 5.0 × 104)	(2.9 × 10−2, 9.1 × 103)	(0.0 × 100, 1.4 × 104)
Knife-to-meat	7.5 × 101	1.3 × 101	2.3 × 100	3.5 × 100
(low dose)	(8.6 × 10−1, 4.6 × 103)	(7.7 × 10−2, 9.1 × 102)	(0.0 × 100, 1.8 × 102)	(0.0 × 100, 2.5 × 102)
Meat-to-cutting board	6.7 × 104	1.2 × 104	2.2 × 103	3.3 × 103
(high dose)	(7.2 × 103, 6.6 × 105)	(8.3 × 102, 1.4 × 105)	(3.5 × 101, 2.8 × 104)	(0.0 × 100, 4.1 × 104)
Meat-to-cutting board	9.1 × 102	1.6 × 102	3.0 × 101	4.4 × 101
(low dose)	(8.0 × 101, 1.2 × 104)	(8.2 × 100, 2.5 × 103)	(4.9 × 10−1, 5.1 × 102)	(0.0 × 100, 7.7 × 102)
Meat-to-knife	1.8 × 105	2.4 × 104	2.0 × 103	1.3 × 103
(high dose)	(1.2 × 105, 2.6 × 105)	(1.6 × 104, 3.5 × 104)	(1.3 × 103, 2.9 × 103)	(8.5 × 102, 1.9 × 103)
Meat-to-knife	1.0 × 103	1.4 × 102	1.2 × 101	7.3 × 100
(low dose)	(6.6 × 102, 1.5 × 103)	(9.0 × 101, 2.0 × 102)	(7.5 × 100, 1.7 × 101	(4.8 × 100, 1.1 × 101)
Transfer from Typical Kitchen Surfaces
Countertop	9.9 × 10−1	1.8 × 10−1	3.3 × 10−2	4.9 × 10−2
	(8.0 × 10−2, 2.0 × 101)	(9.8 × 10−3, 4.2 × 100)	(7.8 × 10−4, 7.9 × 10−1)	(1.6 × 10−5, 1.2 × 100)
Hand towel	2.5 × 10−1	4.6 × 10−2	3.2 × 10−4	0.0 × 100
	(3.5 × 10−2, 2.3 × 100)	(4.2 × 10−3, 4.8 × 10−1)	(0.0 × 100, 8.5 × 10−2)	(0.0 × 100, 1.2 × 10−1)
Dish cloth	2.6 × 10−1	4.7 × 10−2	8.7 × 10−3	1.3 × 10−2
	(3.4 × 10−2, 2.5 × 100)	(4.1 × 10−3, 5.4 × 10−1)	(1.7 × 10−4, 1.1 × 10−1	(0.0 × 100, 1.6 × 10−1)
Kitchen sponge	6.1 × 10−1	1.1 × 10−1	2.1 × 10−2	3.0 × 10−2
	(6.8 × 10−2, 6.9 × 100)	(8.3 × 10−3, 1.4 × 100)	(3.7 × 10−4, 2.9 × 10−1)	(2.0 × 10−4, 4.4 × 10−1)
b. Exposure reduction factor a compared to “no washing”.
		Control Bar	Antimicrobial #1	Antimicrobial #2
Transfer from Meat Preparation Surfaces
Cutting board-to-meat (high dose)		5.4	32	21
Cutting board-to-meat (low dose)		5.6	32	22
Knife-to-meat (high dose)		5.8	32	22
Knife-to-meat (low dose)		5.8	33	21
Meat-to-cutting board (high dose)		5.6	30	20
Meat-to-cutting board (low dose)		5.7	30	21
Meat-to-knife (high dose)		7.5	90	138
Meat-to-knife (low dose)		7.1	83	137
Transfer from Typical Kitchen Surfaces
Countertop		5.5	30	20
Hand towel		5.4	781	>781 b
Dish cloth		5.5	30	20
Kitchen sponge		5.5	29	20

a = Determined by dividing the median exposure dose from “no washing” by the median exposure dose after washing with one of three soaps. b = Cannot be calculated. The median predicted exposure dose was 0.0 × 10⁰ CFU.