EPA 1653 Chlorocathecols 7 Analytes, each 100µg/mL in methanol; unit: 1x1mL 4-Chlorocatechol [2138-22-9] 3,4-Dichlorocatechol 3,6-Dichlorocatechol 4,5-Dichlorocatechol [3428-24-8] 3,4,5-Trichlorocatechol 3,4,6-Trichlorocatechol Tetrachlorocatechol [