Phần này Cho phép Tổng quan về sự phát triển của các giá trị hướng dẫn chung chung. Theo định nghĩa của OECD Để liệt kê trong Phụ lục IPCS = 1 (OECD 2003): Hướng dẫn is''Value giá trị, như vậy là nồng độ trong không khí hoặc nước, nào có nguồn gốc Sau khi phân bổ liều tham chiếu Trong số các phương tiện truyền thông khác nhau càng tốt (đường) tiếp xúc tiếp xúc.''Kết hợp từ tất cả các phương tiện truyền thông tại các giá trị hướng dẫn tương ứng của họ trong suốt quãng đời. | 9 Regulatory Standards Set by Various Bodies Regulatory standards or health-based guidance values in this chapter denoted guidance values for exposure to chemicals in various media such as air drinking water soil and food are set by various international federal and national bodies. This chapter will give an overview of the development of guidance values in general terms and present some examples. GUIDANCE VALUES DEVELOPMENT This section gives an overview of the development of guidance values in general terms. According to the OECD IPCS definitions listed in Annex 1 OECD 2003 Guidance Value is Value such as concentration in air or water which is derived after allocation of the reference dose among the different possible media routes of exposure. Combined exposures from all media at their respective guidance values over a lifetime would be expected to be without appreciable health risk. The aim of a guidance value is to provide quantitative information from risk assessment for risk managers to enable them to make decisions concerning the protection of human health. Guidance values are developed from a standard such as . an Acceptable Tolerable Daily Intake ADI TDI and Reference Dose Concentration RfD RfC . For threshold effects the standard is derived by dividing the No-Observed-Adverse-Effect Level NOAEL or Lowest-Observed-Adverse-Effect Level LOAEL or alternatively a Benchmark Dose BMD for the critical effect s by an overall assessment factor described in detail in Chapter 5. For non-threshold effects the standard is derived by a quantitative assessment described in detail in Chapter 6. To the extent possible guidance values should reflect consideration of total exposure to the substance whether present in air drinking water soil food or other media. Guidance values should be derived for a clearly defined exposure scenario . for ambient air drinking water and soil based on the human exposure factors presented in Section . It should be recognized that
