Combining ex-ante LCA and EHS screening to assist green design: A case study of cellulose nanocrystal foam

The evaluation of environmental credentials for innovative products within the research and design phase of development presents a valuable yet challenging exploit. The research presented here aims to carry out the early-stage environmental assessment of a novel nano material – cellulose nanocrystals (CNC) foam by applying ex-ante life cycle assessment (LCA) supplemented by an environmental, health and safety (EHS) screening. LCA is applied to assess the cradle-to-factory gate environmental impacts along the R&D trajectory from the laboratory synthesis, conceptual design, bench-scale trial to the up-scaled process design. Non-renewable energy use (NREU), greenhouse gas (GHG) emissions and agricultural land occupation (ALO) are the three indicators analysed. The early-stage EHS screening provides a supplementary assessment since the toxicity information is usually missing in the ex-ante LCAs due to lack of information. The EHS screening was conducted in two steps: 1) the (eco)toxicological effects of CNC are analysed by applying in vivo zebrafish assays; and 2)A so-called “block list” scan is performed where all substances used in the production of CNC foam are scanned against valid regulations. The LCA results demonstrate that technology upscaling leads to a steady environmental impact reduction. It is observed that for per kg studied CNC foam, both NREU and GHG emissions were reduced by a factor of 10 along the R&D trajectory from lab scale to upgraded process design, as a result of the design improvements associated with energy-intensive processes and process energy optimisation. Along the studied R&D trajectory the potential ALO was decreased by 83% primarily due to a more efficient recycling of ethanol. The block list scan did not yield highly concerned substances in the manufacturing process. The in vivo zebrafish assay provided valuable insight into the ecotoxicological effects of CNC pointing towards the need for a more rigorous assessment

Daphnid Life Cycle Responses to New Generation Flame Retardants

Relatively hazardous brominated flame retardants (BFRs) are currently substituted with halogen-free flame retardants (HFFRs). Consequently, information on their persistence, bioaccumulation and toxicity (PBT) is urgently needed. Therefore, we investigated the chronic toxicity to the water flea Daphnia magna of two HFFRs, aluminum diethylphosphinate (ALPI) and 9,10-dihyro-9-oxa-10-phosphaphenanthrene-oxide (DOPO). The toxicity of ALPI increased from a 48 h LC50 of 18 mg L-1 to a 21 day LC50 value of 3.2 mg L-1, resulting in an acute-to-chronic ratio of 5.6. This may imply a change in classification from low to moderate toxicity. ALPI also affected sublethal life cycle parameters, with an EC50 of 2.8 mg L-1 for cumulative reproductive output and of 3.4 mg L-1 for population growth rate, revealing a nonspecific mode of action. DOPO showed only sublethal effects with an EC50 value of 48 mg L-1 for cumulative reproductive output and an EC50 value of 73 mg L-1 for population growth rate. The toxicity of DOPO to D. magna was classified as low and likely occurred above environmentally relevant concentrations, but we identified specific effects on reproduction. Given the low chronic toxicity of DOPO and the moderate toxicity of ALPI, based on this study only, DOPO seems to be more suitable than ALPI for BFR replacement in polymers

Daphnid Life Cycle Responses to the Insecticide Chlorantraniliprole and Its Transformation Products

Chlorantraniliprole (CAP) is a newly developed, widely applied insecticide. In the aquatic environment, several transformation products are formed under natural conditions, one by dehydration and others by photoinduced degradation. Data on aquatic ecotoxicity of CAP can mainly be found in registration and regulatory evaluation reports. Moreover, the toxicity of its transformation products and especially effects upon chronic exposure remain completely unknown. Hence, our aim was to investigate the acute and chronic toxicity of CAP and its transformation products to the daphnid <i>Daphnia magna</i>. The results showed that CAP is extremely toxic to <i>D. magna</i>, with an acute and chronic LC₅₀ of 9.4 and 3.7 μg/L, respectively. No effects on daphnid reproduction were observed, but the impact on daphnid survival also affected population growth rate, with an EC₅₀ of 3.5 μg/L. In contrast, no negative effects of the two main degradation products were observed. The present study demonstrated a high sensitivity of nontarget microcrustaceans to CAP. However, the actual risk of CAP in water diminishes with its spontaneous or light-induced degradation into two transformation products, showing no toxicity to the daphnids in the present study

Daphnid Life Cycle Responses to New Generation Flame Retardants

Relatively hazardous brominated flame retardants (BFRs) are currently substituted with halogen-free flame retardants (HFFRs). Consequently, information on their persistence, bioaccumulation and toxicity (PBT) is urgently needed. Therefore, we investigated the chronic toxicity to the water flea <i>Daphnia magna</i> of two HFFRs, aluminum diethylphosphinate (ALPI) and 9,10-dihyro-9-oxa-10-phosphaphenanthrene-oxide (DOPO). The toxicity of ALPI increased from a 48 h LC₅₀ of 18 mg L^–1 to a 21 day LC₅₀ value of 3.2 mg L^–1, resulting in an acute-to-chronic ratio of 5.6. This may imply a change in classification from low to moderate toxicity. ALPI also affected sublethal life cycle parameters, with an EC₅₀ of 2.8 mg L^–1 for cumulative reproductive output and of 3.4 mg L^–1 for population growth rate, revealing a nonspecific mode of action. DOPO showed only sublethal effects with an EC₅₀ value of 48 mg L^–1 for cumulative reproductive output and an EC₅₀ value of 73 mg L^–1 for population growth rate. The toxicity of DOPO to <i>D. magna</i> was classified as low and likely occurred above environmentally relevant concentrations, but we identified specific effects on reproduction. Given the low chronic toxicity of DOPO and the moderate toxicity of ALPI, based on this study only, DOPO seems to be more suitable than ALPI for BFR replacement in polymers