Table 2.

Characteristics and findings for Plant 1 (Wallingford) and Plants 2-10 combined in 2004 NCI update

Characteristic/finding	Plant 1 (Wallingford)	Plant 2–10 (all other plants)
Entry year	1940	1934–1958
No. subjects	4261	21358
Formaldehyde exposure
% Subjects ever exposed	87.7	89.8
% Subjects ever in highest peak category	46.1	20.1
Median AIE (ppm) a	1.023	0.366
(5–95 %-tile)	(.310–1.417)	(.052–1.257)
Median Cum (ppm-years) a	.9	3.2
(5–95 %-tile)	(.1–17.2)	(.06–23.5)
Median Dur (years) a	1.0	13.1
(5–95 %-tile)	(.1–24.4)	(.3–32.1)
Observed deaths and SMRs
All workers
Observed deaths	6	5
SMR-US (expected deaths)	5.44** (1.1)	.97 (5.2)
(95 % CI)	(2–11.85)	(.31–2.26)
SMR-local (expected deaths)	5.57** (1.1)	1.06 (4.7)
(95 % CI)	(2.04–12.12)	(.35–2.48)
Exposed workers
Observed deaths	6	3
SMR-US (expected deaths)	7.23** (.8)	.74 (4.1)
(95 % CI)	(2.65–15.74)	(.15–2.16)
SMR-local (expected deaths)	7.34** (.8)	.82 (3.6)
(95 % CI)	(2.69–15.97)	(.17–2.41)
Unexposed workers
Observed deaths	0	2
SMR-US (expected deaths)	- (.3)	1.81 (1.1)
(95 % CI)	(0–13.55)	(.22–6.53)
SMR-local (expected deaths)	- (.3)	1.88 (1.1)
(95 % CI)	(0–14.20)	(.23–6.80)

^aBased on exposed jobs only with no lag

** p < .01