# Proposition 65 - Substance Calculation

Question:

How do I calculate substance concentrations with regards to Proposition 65?

When doing calculations, Proposition 65 includes the following guidelines:

(1) For an exposure reasonably expected to affect the general population in any geographic area:

(A) The exposed individual ingests two liters of drinking water per day.

(B) The exposed individual inhales twenty cubic meters of air per day.

(C) The exposed individual has a lifespan of seventy years.

(2) For an exposure reasonably anticipated to affect a certain subpopulation of the general population in any geographic area, specific data (if available) relating to that subpopulation shall be used to determine the level of exposure.

(A) In the absence of more specific and scientifically appropriate data, the following assumptions should be made as appropriate:

 Subpopulation Water (liters/day) Air (cubic meters/day) Man (18+ years of age) 2 20 Woman (18+ years of age) 2 20 Woman with conceptus 2 20 Adolescent (10-18 years of age) 2 20 Child (2-10 years of age) 2 15 Infant (0-2 years of age) 1 4

(3) For workplace exposures, the exposed worker inhales ten cubic meters of workplace air per eight-hour day, forty hours per week, fifty weeks per year over a forty-year period. The exposed individual from the general population who occasionally enters a workplace inhales 1.25 cubic meters of workplace air for one hour per month for a seventy-year lifetime.

Calculation for No Significant Risk Levels: