The effects of sole, mixture heavy metals and soil samples was assessed based on the seed (Lactuca sativa L.) germination. In general, tested sole metals were showed considerable sensitivity on the germination, showing following EC50s: As(III) 1.02 mg/L, Cr(VI) 1.33 mg/L, Cu 2.26 mg/L, Cd 2.61 mg/L, As(V) 3.00 mg/L. Though obvious patterns were not observed on the effects by binary mixture metal, generally more synergistic mode was observed rather than antagonistic or additive. No significant correlation between toxicity and total metal contents was observed, but two groups classified according to contaminated arsenic concentration, showed considerable differences. Interactive effects of metals may vary depending on the bioassays used as well as on the mixture metals and their respective concentrations. Therefore, more detailed evaluation, such as with battery of assays, sample grouping and various mixtures, may comprise a useful tool for the assessment of the environmental samples with mixture contaminants.

The regiospecific potential for the reductive dechlorination of 2-, 3-, 4-, 2,3-, 2,4-, and 3,4-chlorophenols (CPs) was studied in mono- and di-CP(DCP) adapted sediment slurries(10% solids). Freshwater sediments adapted to transform 2-CP dechlorinated all tested mono- and di-CPs except 4-CP without a lag period. Adaptation to 2-CP, thus, enhanced the onset of dechlorination of 3-CP and all ortho-substituted CPs tested. Sediment adapted to transform 3-CP dechlorinated all tested CPs, except 4-CP and 2,4-DCP, without a lag period. Sediments adapted lo individual DCPs (2,3-, 2,4-, and 3,4-DCP) exhibited dechlorination (no lag phase) of 2-CP, 2,3-, 2,4-, and 3.4-DCP. Interestingly, meta-cleavage of 3,4-DCP in all tested adapted sediment occurred, while para-cleavage occurred in 3,4-DCP adapted sediment. Sediments adapted to dechlorinate ortho and meta-chlorines exhibited a preference for meta following ortho-cleavage, but not for para-cleavage, while the preference for reductive dechlorination was ortho > meta > para for mono-CPs and ortho > para > meta for DCPs in unadapted freshwater anoxic sediments.