Section 16.31. Application

In the development of water quality criteria for human health protection, the principles of risk assessment and risk management are applied in two distinct ways depending upon the toxic effect to be protected against. Traditional toxicology is developed upon a theory that the ‘‘dose determines the poison’’ (any substance is toxic if the dose becomes large enough). It is generally recognized, however, that for most substances there is a safe level below which no adverse effects will be seen. This ‘‘threshold level’’ approach is in contrast to the ‘‘no threshold level’’ approach generally ascribed to carcinogens.