The yellow coloring is due to the presence of sulfur, which is toxic, as is arsenic, so care should be taken - always wash your hands after handling.
Ihe na-acha odo odo bụ n'ihi sọlfọ ahụ, nke na-egbu egbu, dị ka arsenic, yabụ kwesịrị ịkpachara anya - saa aka gị mgbe ị gachara.