Ecotoxicological effects of typical personal care products on seed germination and seedling development of wheat (Triticum aestivum L.)

\ Biochemical responses of wheat (Triticum aestivum L) seedlings stressed by two typical personal care products (PCPs) - triclosan (TCS) and galaxolide (HHCB) were experimentally investigated to assess their ecological risks. The results showed that wheat shoot and root elongation was significantly inhibited by 50-250 mg L-1 TCS and HHCB. Wheat roots were sensitive to TCS. while shoots were sensitive to HHCB. The median effect concentration (EC50) of TCS and HHCB based on the inhibition of their sensitive sites were 147.8 and 143.4 mg L-1, respectively. Moreover, the damage of wheat seedlings treated by low concentration of TCS and HHCB during a long period cannot be neglected. After a 21-d exposure, 0.2-3.0 mg L-1 TCS and HHCB treatment caused the damage to the accumulation of chlorophyll (CHL), the synthesis of soluble protein (SP), and the activity of peroxidase (POD) and superoxide dismutases (SOD) in different degree. However, different changing trends of these physiological indexes treated by different PCPs were observed after 7-d to 14-d exposures, especially the activity of POD and SOD. The activity of POD and SOD in wheat leaves and roots decreased with an increase in the concentration of TCS and the exposure time. However, the enzyme activities in wheat leaves treated by 0.2-3.0 mg L-1 HHCB increased after a 14-d exposure, and with the prolongation of exposure time. the enzyme activities significantly decreased. The variations in these physiological indexes of wheat could be considered as good biomarkers of serious stress by TCS and HHCB in the environment. (C) 2009 Elsevier Ltd. All rights reserved.