Contents of Mercury and Selenium in Common Edible and Medicinal Insects in Yunnan and Their Correlation Analysis

PurposeTo understand the contents and safety of mercury and selenium in common edible and medicinal insects, a total of 42 species of edible and medicinal insects were collected from Yunnan Province.

MethodThe mercury and selenium contents of these insects were detected by Microwave digestion and inductively coupled plasma mass spectrometry (ICP-MS).

ResultThe mercury content in carnivorous insects was generally higher than that in herbivorous insects, and the mercury content in aquatic insects was much higher than that in terrestrial insects (t-test, P < 0.01). The mercury contents of all tested samples did not exceed the corresponding national standard limits. Selenium content was also the highest in aquatic insects and had a strong correlation with mercury content (R²=0.824 1). While the average selenium content in terrestrial insects was low with big difference exist among different species, and there was no correlation between selenium and mercury contents in terrestrial insects (R²=0.000 8).

ConclusionThe mercury content detection should be enhanced when developing aquatic edible and medicinal insects. Meanwhile, our data also suggests that selenium may have some antagonistic effect on mercury in aquatic insects.