Table 6.
Hazard ratios (95% confidence intervals) and numbers of cases for mortality from breast cancer among female workers with exposure to chemicals
| Chemical | Hazard ratio (95% CI) | No. exposed cases |
|---|---|---|
| Any solvent | 1.19 (0.75–1.91) | 38 |
| 1,1,1-trichloroethane | 2.35 (0.83–6.64) | 4 |
| Acetone | 1.19 (0.55–2.59) | 8 |
| Carbon tetrachloride | 1.06 (0.63–1.77) | 26 |
| Chloroform | - | 0 |
| Freon | 2.71 (1.33–5.50) | 10 |
| Isopropyl alcohol | 2.64 (1.30–5.35) | 10 |
| JP4 gasoline | 1.06 (0.51–2.21) | 9 |
| Metal fumes/dust | 1.77 (0.42–7.37) | 2 |
| Methylene chloride | 2.35 (0.98–5.65) | 6 |
| Methylethyl ketone | 1.61 (0.81–3.20) | 11 |
| Nitroglycerine | - | 0 |
| O-dichlorobenzene | 0.64 (0.09–4.74) | 1 |
| Other alcohols | 1.57 (0.38–6.55) | 2 |
| Perchloroethylene | 0.48 (0.07–3.50) | 1 |
| Silica | - | 0 |
| Solder flux | 2.76 (1.32–5.76) | 9 |
| Stoddard solvent | 1.03 (0.60–1.76) | 23 |
| Styrene | 1.30 (0.18–9.54) | 1 |
| Toluene | 1.44 (0.76–2.74) | 13 |
| Xylene | - | 0 |
| Zinc chromate | 1.18 (0.58–2.40) | 10 |
Cox regression model: time variable = age, covariate = race
Referent group for all models: female workers with no chemical exposure (n=1,983)
A “-”indicates the hazard ratio cannot be calculated due to empty cell(s)