1 Chemicals used in industry, science, photography, as well as agriculture, horticulture and forestry, especially potassium permanganate, sodium permanganate, calcium peroxide, magnesium peroxide, hydrogen peroxide, sodium persulfate, potassium persulfate and ammonium persulfate, anhydrous ferrous sulfate and hexahydrate ferrous sulfate, sodium silicate, sodium tetrasulfide, sodium ferrate and potassium ferrate, sodium sulfide, lactulose, enzymes, complexing and chelating chemical agents; fertilizers