The Impacts of Environmental Characteristics to Groundwater Quality and Influencing Toxicity in Seashore Area

摘要

Groundwater is an important substitute water source in seashore zone of Taiwan owing to its accessibility and stability. However, the potential toxicity derived from inorganic metal, organic contaminant leaking from industrial area, soil salinity and disinfection by-products (DBPs) has attracted governors' attention to the health risk in groundwater usage. To figure out the impacts of environmental factors to the patterns of pollutant as well as to bio-toxicity in groundwater, Redundancy analysis (RDA) technology is utilized to assess their causalities in this study. Results pointed out that inorganic arsenite concentration is highly related to biological toxicity. The main species of HAAs is bromodichloroacetic acids and dichloroacetic acids, they was dominated by bromide (Br~-) concentration and humic substances, respectively. The existence of bromide in groundwater is resulted from soil salinity due to seawater incursion. For water safety, the removal of HAAs and arsenite are necessary, and effective limit of HAAs generation should devote to limit the increase of Br~- and humic substances. Thus, RDA was demonstrated a useful tool to investigate the causal relationship among the environment variables, pollution and toxicity in environmental studies.