Levels of Concern—Low, Moderate, and High—for Each Hazard

The GHS defines hazard categories for many, but not all, chemical hazards. Immune system effects and neurotoxicity, for exam- 

THE GREEN SCREEN FOR SAFER CHEMICALS EVALUATING FLAME RETARDANTS FOR TV ENCLOSURES 17 

The US ERA DfE Program defined threshold values for high, moderate, and low levels of concern for environmental fate, ecotoxicity, and human health effects (as part of its assessment of alternatives to pentaBDE). These threshold values were the starting point for defining many of the Green Screen threshold values. Table 3 summarizes the Green Screen threshold values for each level of concern for each hazard. The details and rationale behind each threshold value are described below. 

Environmental Fate Persistence and Bioaccumulation. As Table 1 reveals, there is wide variation in setting threshold values for high persistence and high bioaccumulation potential, even within the US EPA. These differences reflect specific organizational goals, interpretations of science, as well as points in time when the values were developed. The threshold values in the Green Screen for persistence and bioaccumulation are set to be highly protective of human health and the environment. 

High Persistence. The threshold values for high persistence in the Green Screen are 

---