Fig. 2: Exposure–response relationship of trihalomethanes in residential tap water, nitrate waterborne ingestion, and lifetime total swimming pool hours with chronic lymphocytic leukemia (CLL); expressed as odds ratios (ORs) and 95% confidence intervals (CIs).

Smoothed spline with three degrees of freedom from general additive models adjusted for region, age, sex, and educational level, family history of hematologic malignancy, body mass index, smoking, physical activity, ever worked in farming or agriculture, alcohol consumption. The dashed lines represent the 95% confidence intervals (CIs).