Is the Cooking Salt Safe in China? Assessment of Chemical Contaminants in Cooking Salt

A Cross-Sectional Survey of Iodized Salt Usage in Dining Establishments - 13 PLADs, China, 2021-2022

What is already known about this topic?

The National Iodine Deficiency Disease Surveillance system is exclusively focused on monitoring cooking salt used within households. Currently, there is a lack of nationally representative data on the use of iodized salt in dining establishments.

What is added by this report?

This study evaluated 7,889 salt samples obtained from dining establishments located in 13 provincial-level administrative divisions across China. The findings indicated that coverage rate of iodized salt (CRIS) and the consumption rate of adequately iodized salt (CRAIS) were found to be 95.2% and 90.2%, respectively. Further, 880 samples were classified as iodized salt and 804 as adequately iodized salt. In coastal areas, the CRIS and CRAIS showed a significant decrease to 77.1% and 70.5%, respectively, when compared to the inland regions (P<0.01).

What are the implications for public health practices?

The data compiled could potentially fill the void in the national data concerning the use of iodized salt in dining establishments throughout China. It is of the utmost importance to increase the awareness of restaurant operators, particularly those located in coastal areas, about the benefits of iodine supplementation. Moreover, they should be encouraged to use adequately iodized salt.

Fluoride Exposure from Soybean Beverage Consumption: A Toxic Risk Assessment

The consumption of vegetable milk as a substitute for cow's milk has increased in recent years. Of all the vegetable beverages on the market, soy is the most widely consumed. Soy is exposed to contamination by different chemical elements during harvesting. In this study, the concentration of fluoride in soy beverages was analyzed. Fluoride is an element that in high concentrations can be toxic, causing dental and bone fluorosis. The aims of the study were (i) to analyze the fluoride concentration in 30 samples in the most popular brands (A-Brand, B-Brand, C-Brand) of soybean beverages by a fluoride ion selective potentiometer and (ii) to evaluate the toxicological risk derived from its consumption. The fluoride concentrations were 15.5 mg/L (A-Brand), 11.3 mg/L (B-Brand) and 8.5 mg/L (C-Brand). A consumption of 1 to 3 servings/day was established. One serving (200 mL) of soybean beverage offered a contribution percentage over the ADI (acceptable daily intake) for infants and children. Teenagers and adults did not exceed the ADI (10 mg/day). The consumption of soy beverages contributes significantly to the daily intake of fluoride, which could exceed the ADI with a consequent health risk. It is recommended to control the fluoride levels in the raw material and in the final product to assure the safety of these products.

Iodine in household cooking salt no longer plays a crucial role in iodine status of residents in Tianjin, China

PURPOSE

The contribution of household cooking salt to population iodine status is decreasing in China, the applicability of the coverage rate of iodized salt (IS), proportion of adequately iodized salt (AIS), and salt iodine concentration (SIC) of household cooking salt used for iodine status assessment of residents requires further investigation.

METHODS

Through the IDD control project, 16,445 children and 4848 pregnant women were recruited from Tianjin, China and the relationship between the coverage rate of IS, proportion of AIS, SIC, and population iodine status was analyzed. Additionally, through the thyroid health survey project, 856 children with IS or noniodized salt were recruited. The effects of different household cooking salts on individual iodine status and thyroid health were analyzed.

RESULTS

After adjusting for confounding factors, no relationship was found between the coverage rate of IS, proportion of AIS, SIC of household cooking salt, and iodine status of children and pregnant women (all P > 0.05). No differences in levels of thyroid function and structural indicators were found in children with different household cooking salts (all P > 0.05). Additionally, no relationship was found between noniodized salt exposure and goiter, overt hyperthyroidism, overt hypothyroidism, thyroid nodules, antibody single positivity, or subclinical hypothyroidism (all P > 0.05).

CONCLUSION

Iodine in household cooking salt no longer plays a crucial role in iodine status in Tianjin, China. Other indicators must be identified as beneficial supplements for precise iodine status evaluation not only in Tianjin but also in other large cities in China.