Life cycle assessment of embodied human health effects of building materials in China

With the rapid development of the construction industry in China, a large number of building materials have been consumed and resulted in huge pressure to the resources and environment. Based on localized construction material inventory data, China-specific characterization factors in LIME-3 (Life Cycle Impact Assessment based on Endpoint Modeling) was used to evaluate the environmental impact of human health. It is found that ceramic tiles and steel have high burden of human health impact, which are 2.98E-05 DALY and 1.72E-05 DALY, respectively, while gravel and natural sand have relatively low impact, which are 5.12E-08 DALY and 4.30E-09 DALY, respectively. Among the five midpoint impact categories (climate change, air pollution, photochemical oxidant formation, water consumption and human toxicity) that have effects on “human health”, the contribution proportion of different building materials vary significantly. The environmental impact assessment results of different building materials on “human health” under LIME-3 and ReCiPe were compared. Results show that the burden of human health impact for ceramic tile under LIME-3 is nearly 67 times that under ReCiPe, which is mainly due to the different proportion of human toxicity in the endpoint of human health and the difference between the two methods in material characterization factors. For high impact burden materials such as steel and ceramic tiles, impact mitigation strategies have been proposed, such as applying electric arc furnace steel making to improve the productivity of steel and the recycling rate of scrap steel, and promoting new dry powder production processes to reduce alkanes and fluorides emission. This study considered an additional midpoint impact category (human toxicity) based on the LIME-3, directing the impact assessment against indicators located at the end of the impact pathway, such as human health. A database of characterization factors of human toxicity for dozens of substances or components has been constructed. Efforts were made in the direction of developing the application of the most widely used impact assessment methods.