Probabilistic Health Risk Assessment of Iodine Exposure in Bangladesh

In this study, the concentrations of iodine in household salt samples (n = 690) were determined by following the iodometric titration method, and the health risks of Bangladeshi people were assessed based on the semi-probabilistic approach and the US Environmental Protection Agency (USEPA) deterministic model. After adjusting 20% of cooking losses, the iodine concentration (mean, range) in salt samples of Phultala, Dighalia, Terokhada, Rupsha, Batiaghata, Dumuria, Paikgacha, Koyra, Dacope, and KCC was (29.68 +/- 8.67, 14.39-48.26), (31.05 +/- 6.68, 15.24-43.18), (26.94 +/- 5.57, 16.09-45.72), (24.33 +/- 5.61, 12.70-37.26), (26.69 +/- 6.73, 10.16-44.87), (27.20 +/- 8.44, 9.31-53.34), (27.71 +/- 8.09, 8.46-47.42), (28.39 +/- 7.80, 11.01-46.57), (28.20 +/- 7.97, 3.38-49.10), and (29.21 +/- 6.62, 18.62-40.64) mg/kg, respectively. The iodine contents in 97.25% of samples were within the standard fortification level of Bangladesh (15-50 mg/kg), while 2.61% of samples were below this limit. The semi-probabilistic risk assessment studies showed that 80.14% of samples at a low ingestion rate could provide optimal nutrition (150-299 mu g/day) to the whole population. Contrarily, at medium, moderate-high, and high consumption rates 34.93%, 65.22%, and 85.94% of samples, respectively, belonged to above the requirements to excessive exposure categories (300-1100 mu g/day), which might cause iodine-induced diseases. The target hazard quotient (THQ) values for the adults in most of the samples were within the threshold risk limit (THQ < 1.0), whereas THQ values in 6.82% to 85.97% of samples for the children at low to high ingestion rates, respectively exceeded this limit, which revealed that the adults were almost safe, but the children might face non-carcinogenic health effects. Therefore, regular monitoring of iodine concentration in iodized salts should be done to prevent iodine deficiency or iodine-induced disorders.

Automated summary

In this study, the iodine concentrations in household salt samples in Bangladesh were measured, and the health risks were assessed. Most samples met the standard fortification level, but at high consumption rates, excessive exposure to iodine may cause health issues. Adults were relatively safe, but children may face non-carcinogenic health effects. Regular monitoring of iodine concentration in iodized salts is needed.