The total Iodine and Iodate-iodine content of sea-water

Iodine in sea water samples from the Northeast Pacific and Arctic Oceans was determined by two independent methods of analysis, one of which was also capable of determining iodate. Both oceans showed a constant iodine-chlorinity ratio of 3·3 × 10⁻⁶ at depths from 250–4000 metres. Some significant variation was observed in the iodine chlorinity ratio in the surface layers. In the North Pacific from one- to two-thirds of the total iodine was present as iodate, with no discernible trends with depth or location. In the Arctic, the iodate increased with depth — from a minimum near the surface to a maximum at 500–1000 metres-where 100 per cent of the iodine was found to be iodate. More iodate was present in the Arctic from 200–2000 metres than was present in any North Pacific sample.

Inland waters of the State of Washington showed iodine-chlorinity ratios about 15 per cent lower than oceanic stations, probably due to accumulation of iodine by benthonic algae.