Low dosage fluorine ameliorates the bioaccumulation, hepatorenal dysfunction and oxidative stress, and gut microbiota perturbation of cadmium in rats.

Many "hot spot" geographic areas around the world with soils and crops co-polluted with cadmium (Cd) and fluorine (F), two of the most representative pollutants in the environment. However, it still exists argumentative on the dose-effect relationship between F and Cd so far. To explore this, a rat model was established to evaluate the effects of F on Cd-mediated bioaccumulation, hepatorenal dysfunction and oxidative stress, and the disorder of intestinal microbiota as well. 30 healthy rats were randomly assigned to Control group (C group), Cd 1 mg/kg (Cd group), Cd 1 mg/kg and F 15 mg/kg (L group), Cd 1 mg/kg and F 45 mg/kg (M group), and Cd 1 mg/kg and F 75 mg/kg (H group) for 12 weeks by gavage. Our results showed that Cd exposure could accumulate in organs, cause hepatorenal function damage and oxidative stress, and disorder of gut microflora. However, different dosages of F showed various effects on Cd-induced damages in liver, kidney, and intestine, and only the low supplement of F showed a consistent trend. After low supplement of F, Cd levels were declined by 31.29% for liver, 18.31% for kidney, and 2.89% for colon, respectively. The serum aspartate aminotransferase (AST), blood urea nitrogen (BUN), creatinine (Cr), and N-acetyl-ß-glucosaminidase (NAG) were significantly reduced (p < 0.01); The activity of superoxide dismutase (SOD) was elevated and mRNA expression level of NAD(P)H quinone oxidoreductase 1 (NQO1) was decreased in the liver and kidney (p < 0.05). Moreover, low F dosage up-regulated the abundance of Lactobacillus from 15.56% to 28.73% and the 6.23% of F/B ratio was declined to 3.70%. Collectively, this highlights that low dosage of F might be a potential strategy to ameliorate the hazardous effects by Cd-exposed in the environment.

Distributions of Heavy Metals in Rice and Corn and Their Health Risk Assessment in Guizhou Province.

Long-term exposure to heavy metals from high geological background area may lead to varieties of diseases. Therefore, risk assessment from agricultural products in these areas was crucial to ensure the health of customers. However, the effects of geological background on distributions of heavy metals and their accumulation in plant remain unclear. This study aimed to determine the distributions of mercury (Hg), cadmium (Cd), arsenic (As), lead (Pb), chromium (Cr) and copper (Cu) in 1036 corn and rice samples collected from 9 locations in Guizhou province and to evaluate their health risks. The concentrations of Hg, Cd, As, Pb, Cr and Cu in these two crops were analyzed by inductively coupled plasma-mass spectrometry (ICP-MS), and their health risk were estimated by the target risk quotient approaches. Results showed that the mean concentrations of Hg, Cd, As, Pb, Cr and Cu in corn and rice were 0.01, 0.07, 0.06, 0.27, 0.56 and 1.86 mg/kg which were lower than their respective maximum allowable concentrations (MAC) of 0.02, 0.20, 0.70, 0.20, 0.50 and 10.00 mg/kg except Pb and Cr. The concentrations of Cr and Cu in corn were higher than in rice while Cd, As and Pb in rice were higher than in corn. Moreover, the distributions of Hg, Cd and Cu in corn and rice samples were mainly observed from QDN located at southeast of Guizhou province while Pb, As and Cr were most detected at ZY, QXN and BJ areas, southwest zone. The hazard indices (HIs) values for corn and rice were 0.20 and 2.61. The high HIs (> 1) in rice indicated that the health risk of heavy metals in rice was relatively high and Pb was the major component that attributed to the risk, followed by Cd. These results could provide a reference for the distributions of heavy metals in agricultural products in Guizhou province under crop cultivation conditions, and to provide scientific basis for health risk assessment and ensure food safety.