The study looked at how different metal chlorides affected the growth and reproduction of Eisenia fetida worms. They found that certain concentrations of NaCl had sublethal effects, reducing cocoon production but increasing body mass. Other metal chlorides like KCl, CaCl2, and MgCl2 did not harm the worms but suppressed their reproduction. Some metal chlorides like CoCl2, CuCl2, and NiCl2 were extremely toxic, causing a decrease in body mass and stopping reproduction altogether. Overall, the metal chlorides had varying effects on the worms' growth and reproduction, with some being more harmful than others.