Canadian Beach Cohort Study

We will examine a graded classification of this exposure based on individuals' minimum level of water contact: 1) no water contact; 2) minimal contact; 3) body immersion; 4) swallowed water. Minimal contact is defined as water contact that does not result in body immersion (e.g., wading below one's waist, boating, fishing). Body immersion is defined as entering the water above one's waist (e.g., swimming, surfing, snorkelling), and swallowing water as ingestion of any amount of water.