Assessment of information availability for environmental impact assessment of engineered nanomaterials

Environmental impact assessments of engineered nanomaterials can be hampered by the lack of data/information and thus delay the development of effective regulatory policies. To address this issue, a systematic approach (termed here “IANano”) was developed and demonstrated for assessing information availability for environmental impact assessment (EIA) of engineered nanomaterials. In IANano, following the typical EIA process, the required information elements for exposure and hazard potential assessments are classified based on major categories, sub-categories, and attributes. Scores for the different information attributes are then assigned, based on a selected scoring scale and weights, and aggregated up to the level of exposure and hazard potential information (EPI and hazard potential information [HPI], respectively), considering both available and unavailable information, via the Dempster-Shafer algorithm. The utility of IANano was demonstrated for several specific EIA scenarios for nano-TiO₂, nano-Cu-CuO, and nano-ZnO. For the three nanomaterials, in each of the different EIA scenarios, the EPI scores were lower than the HPI scores, consistent with the more abundant information available for hazard attributes. For nano-TiO₂, the exposure potential information (EPI) scores were in the range of 0.33–0.72 and higher by 60–50% and 42–46% relative to nano-Cu-CuO and nano-ZnO, respectively, for all EIA scenarios. For the scenario of direct release of engineered nanomaterials to the aquatic environment, the HPI scores for nano-Cu-CuO and nano-ZnO were greater by factors of 2.6 and 1.3, respectively, relative to the EPI scores. Results of the present study suggest that information screening, as illustrated via IANano, can be valuable for ranking the adequacy of the available information for conducting specific EIAs and for identifying information needs.