Table 6.
Categorization of cumulative exposure variables (μg/L –months) within the Camp Lejeune cohort
| Category | Reference level | Low exposure | Medium exposure | High exposure |
|---|---|---|---|---|
|
Cumulative tetrachloroethylene (for >1 μg/L –months: mean = 402.6, median = 269.5) | ||||
|
Level* |
≤ 1 |
>1 - 155 |
>155 - 380 |
>380 – 8,585 |
|
Number (%) |
66, 582 (43.0%) |
28,230 (18.2%) |
27,255 (17.6%) |
32,865 (21.2%) |
|
Cumulative trichloroethylene (for >1 μg/L –months: mean = 6,369.3, median = 5,289.0) | ||||
|
Level* |
≤ 1 |
>1 – 3,100 |
>3,100 – 7,700 |
>7,700 – 39,745 |
|
Number (%) |
64, 584 (41.7%) |
31,069 (20.1%) |
27,638 (17.8%) |
31,641 (20.4%) |
|
Cumulative vinyl chloride (for >1 μg/L –months: mean = 458.9, median = 360.6) | ||||
|
Level* |
≤ 1 |
>1 - 205 |
>205 - 500 |
>500 – 2,800 |
|
Number (%) |
66, 470 (42.9%) |
27,651 (17.8%) |
28,063 (18.1%) |
32,748 (21.1%) |
|
Cumulative benzene (for ≥2 μg/L –months: mean = 104.7, median = 83.2) | ||||
|
Level* |
< 2 |
2 - 45 |
>45 - 110 |
>110 - 601 |
|
Number (%) |
64, 580 (41.7%) |
24,579 (15.9%) |
31,838 (20.5%) |
33,935 (21.9%) |
|
Cumulative TVOC (for >1 μg/L –months: mean = 9,605.1, median = 7,652.8) | ||||
|
Level* |
≤ 1 |
>1 – 4,600 |
>4,600 – 12,250 |
>12,250 - 64,016 |
| Number (%) | 57, 328 (37.0%) | 35,432 (22.9%) | 29,687 (19.2%) | 32,485 (21.0%) |
*An individual’s maximum amount of cumulative exposure (μg/L –months) at the end of follow-up.
N = 154,932.