While global human health-related impacts can be quantified with LCA (e.g., carcinogenics and non-carcinogenics in TRACI 141-143 ), LCIA methods often have toxicity models (e.g., USEtox in TRACI ) and embedded assumptions about the environmental fate of contaminants, human exposure, and human health effects (including dose response relationships). Consequently, the human health category within LCA includes modeled impacts spread over large spaces and time scales, and these "averaged" impacts do not explicitly consider localized effects from chemicals or pathogens that may be particularly relevant to project stakeholders. Therefore, when local health risks from exposure to chemical and microbial hazards are of concern, impact indicators (e.g., benchmark quotient of risk level 146 ) should be selected and evaluated with corresponding techniques (e.g., QRA). For example, if the objective of the QSD study is to guide early-stage technology research and development rather than local deployment, then it may be appropriate to focus on global human health impacts through existing impact categories embedded in LCA (e.g., as in ). In contrast, when QSD is used to inform site-specific decisions (e.g., planning sanitation system deployment in a specific community), QRA can be employed and local data should be collected for the results to be representative (e.g., measuring pathogen concentrations, quantifying local exposure ).