EPA Method 507/1656 Nitrogen Phosphorus Back Catalog number: 31782 Manufacturer: ABSOLUTE STANDARDS Availability: In the manufacturer's stock Price on request - + Recommended 8-B-23-CDF 8-Bromo-2,3-dichlorodibenzofuran, 1.2ml x 50ug/ml, toluene Price on request 66189 2,3,3',4,4',5,5'-Heptachlorobiphenyl (189) Price on request 675870 Metazachlor OA, 100 µg/ml, Acetonitrile, 1ml Price on request