This document specifies a method for the determination of organically bound halogens fluorine, chlorine, bromine and iodine which are adsorbable on activated carbon. Adsorption takes place on activated carbon packed in columns.

The method is applicable for the determination of:

• ≥ 2 µg/l AOF, expressed as F;
• ≥ 10 µg/l AOCl, expressed as Cl;
• ≥ 1 µg/l AOBr, expressed as Br;
• ≥ 1 µg/l AOI, expressed as I.

The method is applicable for the determination of adsorbable organically bound fluorine, chlorine, bromine and iodine in water, e.g. in groundwater, surface water, bank filtrate, drinking water, aqueous eluates, cooling water and wastewater.

The working range is limited by the capacity of the activated carbon, the process blank and the capacity of the chromatographic separation column. Sample dilution into the working range can be required.

The range of application can be extended to lower concentrations with lower process blanks e.g. using low blank activated carbons.

The method can also be applied for samples containing suspended solids. Halogens adsorbed on the suspended solids (e.g. undissolved halides) are also determined. Filtration of the sample prior to analysis using a membrane filter (0,45 µm) allows the separate determination of dissolved adsorbable and particulate bound fractions of organically bound fluorine, chlorine, bromine or iodine.

Results from an international interlaboratory trial are presented in Annex K.