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EPA EcoBox

EPA EcoBox Tools by Stressors

A stressor (or agent—an alternative term often used) is defined as any chemical (e.g., toxics or nutrients), physical entity (e.g., dams, fishing nets, or suspended sediments), or biological entity (e.g., non-native or genetically engineered organisms) that can induce an adverse response. The term “stressor” is used broadly to encompass entities that cause primary effects, and those primary effects can cause secondary (i.e., indirect) effects (U.S. EPA, 1998). This tool set is presented as four modules:


See information and tools related to chemical stressors



See information and tools related to biological stressors



See information and tools related to physical stressors