What are safe harbor numbers?

To guide businesses in determining whether a warning is necessary or whether discharges of a chemical into drinking water sources are prohibited, OEHHA has developed safe harbor levels for many Proposition 65 chemicals.  A safe harbor level identifies a level of exposure to a listed chemical that does not require a Proposition 65 warning.   A business does not need to provide a warning if exposure to a chemical occurs at or below these levels. These safe harbor levels consist of No Significant Risk Levels for chemicals listed as causing cancer and Maximum Allowable Dose Levels for chemicals listed as causing birth defects or other reproductive harm. OEHHA has established more than 300 safe harbor levels and continues to develop more levels for listed chemicals.