Abstract Continuous generation of volatile iodine species based on chemical or photochemical oxidation may be further improved using a sequential (photo)chemical vapor generation/pneumatic nebulization/programmable-temperature spray chamber (P)CVG–PN–PTSC system providing the benefits of a temperature-controlled ICP sample introduction technique. Two experimental setups were designed and optimized to obtain the higher sensitivity. In the CVG mode, the sample and the oxidizing solution are continuously pumped and mixed directly before entering a concentric nebulizer placed in the PTSC, while in PCVG mode the sample solution containing 3% v/v acetic acid is on-line exposed to UV radiation before nebulization. A study was conducted to evaluate the performance of a new CVG–PN–PTSC technique for determination of iodine element by ICP-OES. The ICP-OES intensity is enhanced by a factor of up to 12 by prior oxidation of the iodide to volatile species combined with subsequent pneumatic nebulization, presumably because of increased analyte transport efficiency into the plasma. Next, by heating the spray chamber at 40 °C, signal intensities were enhanced by a factor of 3 as compared to the results found at room temperature. Furthermore, using an elevated temperature of the spray chamber slightly increased plasma robustness (MgII to MgI line intensity ratio exceeds 10), likely as a result of increased water vapor that improves plasma stability as well as sensitivity. Both systems were optimized in a wide range of chemical and operating parameters. With both CVG and PCVG–PN–PTSC, the slopes of analytical working graphs of ICP-OES are improved by over an order of magnitude for iodine compared to those with a conventional pneumatic nebulization. Generally, for determination of iodine, the technique exhibits a linear dynamic range of 3 orders of magnitude. For iodine, LODs of 11 ng mL − 1 were achieved in CVG mode and 17 ng mL − 1 in PCVG mode at 206.15 nm. The technique also gave good short-term stabilities below 2% RSD for both modes. Finally, a continuous CVG technique using sodium nitrite exhibits a better analytical performance than the PCVG mode. Quantitative determination of iodide in mineral water is preferentially carried out by the standard addition procedure. The proposed methodologies were validated with determining of trace iodide in simulated seawater in 2% nitric acid standard reference material CRM-SW, giving rise to satisfactory results.