(a) lysosomal membrane stability characterized by neutral red retention time (NRRT), (b) concentration of intracellular calcium ions and (c) potential difference in the mitochondrial membrane (ΔΨm) measured by FL2 fluorescence intensity determined by flow cytometry assays; (d) metallothionein (MT) level determined with assay kits; and (e) heat shock proteins (HSP 70) determined by western blot in extruded coelomocytes of treated E. fetida. (a) and (d) were determined on days 7, 14, 21 and 28; (b), (c) and (e) were determined on day 28 day after exposure in spiked natural soil; CK, H-1, H-2, H-3, and H-4 (n = 4; error bars, SEM). Refer to Fig 1 for details of other annotations (S1 Data).