National and International agencies establish drinking water guidelines based on objectives which combine health protection, aesthetics, and the efficacy of metal removal. Recent examples of requests by BC agencies to BCCDC around selenium, arsenic, manganese and lead in water illustrate the need to appreciate the objectives and evidence supporting the guideline. Here we review how aggregate exposure is compared to effects on health (or other endpoint), how acceptable population all-source intake is set, and review how water consumption is apportioned within overall acceptable exposure. Lesson: read the fine print.

The views and opinions expressed by invited webinar presenters do not necessarily reflect those of the NCCEH and our funder, the Public Health Agency of Canada.