Simultaneous determination and dietary intake risk assessment of 60 herbicide residues in aquatic products.

A sensitive and rugged analytical method was first established to simultaneously determine 60 herbicides in aquatic products with gas chromatography-tandem mass spectroscopy (GC-MS/MS). After extraction with acetonitrile (MeCN), NaCl and anhydrous Na2SO4 were added, concentrated supernatants were directly passed through the Carb/NH2 solid phase extraction column. Then, the cartridge was rinsed with elution solution (MeCN/toluene, 3:1, v/v), followed by GC-MS/MS analysis with multiple reaction monitoring. An excellent linearity (1.0-100.0 µg/L) with R2 value of ≥0.9991 was obtained, and the limits of quantification were 0.018-3.852 µg/kg. Satisfactory recoveries (70.8 %-117.6 %) with RSDs below 11.0 % of herbicide residues were obtained at spiked levels of 0.010-0.050 mg/kg. Furthermore, herbicide residues in actual aquatic products were analyzed, and the acute/chronic risk assessment of dietary exposure was carried out. The wide use of herbicides for controlling weed and removing moss and harmful algae may obviously increase the risk of contamination of the aquaculture environment and fishery products. Therefore, considerable attention and more research are necessary to monitor residue levels for herbicides in aquatic products and ensure the quality of marine products and consumer safety.

Benefit-risk assessment of dietary selenium and its associated metals intake in China (2017-2019): Is current selenium-rich agro-food safe enough?

Dietary consumption of selenium-rich agro-food is an effective way to avoid selenium deficiency diseases, however, over consumption of selenium-rich agro-food will result in potential risk of selenosis and problems with associated metals. In this study, we measured the concentrations of selenium and its associated metals in 2756 common and 4894 selenium-rich agro-food samples in 10 regions of China. We found that selenium-rich rice, flour, edible fungi and algae, meat, and tea contain higher levels of associated metals than other selenium-rich agro-food samples. Increasing the consumption of selenium-rich agro-food could make the actual intakes (AIs) of selenium for all population to meet respective recommended daily intakes (RDIs). Benefit-risk assessment results indicated that increasing the consumption of selenium-rich agro-food make AIs of selenium for all populations meet RDIs, chromium intakes for people under 18 years old exceed provisional tolerated daily intake (PTDIs), while arsenic and cadmium intakes are close to PTDIs. The main dietary contributors of selenium, chromium, arsenic and cadmium were meat, edible fungi and algae, rice, and rice, respectively. The study supported the consumption of selenium-rich agro-food for effective selenium supplement, but also emphasized potential risk from associated metals in selenium-rich agro-food, especially chromium.

Determination of Selenium in Common and Selenium-Rich Rice from Different Areas in China and Assessment of Their Dietary Intake.

In this study, 41 common rice varieties and 211 selenium-rich rice varieties from ten representative areas in China were collected in 2017-2019. The selenium contents of rice were analyzed with optimized inductively coupled plasma mass spectrometry (ICP-MS). Selenium concentrations of common rice and selenium-rich rice ranges were 0.81-7.26 and 0.76-180.73 µg/100 g, respectively. The selenium contents in selenium-rich rice from different areas were significantly different (p < 0.001) while those in common rice from different areas were not. The selenium-rich rice in Harbin and Keshan showed the lowest selenium level and those from selenium-rich areas (Enshi and Ankang) were highest. Based on the estimation of the risk assessment software @risk7.0 (Palisade Corporation, New York, NY, USA), the consumption of selenium-rich rice can effectively increase dietary selenium intake for the population. However, the risk index of P95 (Percentile 95) selenium exposure at the tolerable upper intake level for children at 2-14 years old exceeded 100%, with potential risk currently. Therefore, the consumption of selenium-rich rice should be properly monitored for young children and adolescents.