Various industrial activities lead to environmental pollution by heavy metals. Toxic heavy metals enter the food chain of dairy cows through feed and water, then transferred into milk. This study investigated the correlations of heavy metal contents between individual cows' milk, water, silage and soil. The relationships between heavy metal contents in individual cows' milk with milk protein, fat, lactose, solid nonfat (SNF), and total solids (TS) were analysed. Concentrations of Pb, As, Cr, and Cd in milk, silage and water were measured by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Lead, Cr, and Cd in soil were measured by Atomic Absorption Spectrometry (AAS), and As was detected by Atomic Fluorescence Spectrometry (AFS). One-way non-parametric tests and Spearman correlation analyses were performed using SAS 9.4 software. Levels of Pb and Cd in milk from the unpolluted area were significantly lower (P < 0.01) than those from industrial area. Significantly higher (P < 0.01) As residue was recorded in milk from unpolluted area. Positive correlation of Pb was observed between milk and silage, and As in milk was positively correlated with As in water. Content of As in milk was slightly (r ¼ 0.09) correlated with As in silage, even though strong positive correlation (r ¼ 0.78) was observed between silage and water. Positive correlations were observed for Cr and Cd between milk and silage, as well as milk and soil. Positive correlations were observed in Pb-protein, Cr-protein, and Cd-lactose; other positive correlation coefficients were nearly equal to zero. The results suggest that industrial activities lead to possible Pb and Cd contamination in milk. Drinking water could be the main source of As contamination in cows. No clear relationship was found between milk composition and heavy metals contents in milk. Water and soil on the farm had a partial contribution to heavy metal contamination in milk.

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This large scale study investigated the spatial variability of Pb, As, and Cd contents in raw milk within and between the 10 main milk producing areas in China. A total of 997 raw milk samples were analysed by inductively coupled plasma mass spectrometry (ICP-MS). Mean values of Pb, As, and Cd in milk were 1.75 μg/L, 0.31 μg/L, and 0.05 μg/L, respectively. The highest level of Pb and As was present in area C, and Cd was highest in area J. The standard deviation suggested a higher heterogeneity of milk heavy metal contamination within area than between areas. Levels of Pb, As, and Cd showed significant differences between studied areas. The estimated root mean squared standardised error obtained by the cross-validation suggested a differentiated quality of Pb, As, and Cd modelling between areas: the predictions obtained were sometimes overestimated or underestimated. These results can be used to define a more appropriate sampling procedure for heavy metal contaminate distribution in raw milk for improved future control of milk contamination by heavy metals in the studied areas. The significant positive correlations between concentrations of Pb-Cd, As-Cd, and Pb-As were observed in nine, six and five areas, respectively. No significant negative correlations were observed. The observed variability of correlation values suggested a different pollution source for Pb, As, and Cd in milk between areas. Further studies are required to clarify the relationships between the contamination of raw milk by heavy metals and the herd environment.

In this study, the content of chromium (Cr), arsenic (As), cadmium (Cd) and lead (Pb) in domestic and imported infant formulas from Beijing, China were analyzed using inductively coupled plasma mass spectrometry. The content of Cr, As, Cd and Pb was 2.51–83.80, 0.89–7.87, 0.13–3.58 and 0.36–5.57 μg/kg, respectively. Even though there were no significant differences in toxic elements content between domestic and imported infant formulas, Cd content was slightly lower in domestic samples. The estimated daily intake (EDI), target hazard quotient (THQ) and hazard index (HI) were calculated for infants between 0.5 and 5 y of age. The EDIs were lower than the oral reference doses. THQ of As, Cr, Cd and Pb was 0.027–0.103, 0.024–0.093, 0.0025–0.0090 and 0.0015–0.0046, respectively. HI values were 0.055–0.192 for boys and 0.056–0.209 for girls and were inversely associated with age with a threshold < 1. The non-carcinogenic risk value were in the safe range, indicating that exposure of As, Pb, Cr and Cd from infant formulas do not represent a health risk in China.

In recent years, high levels of hormone residue in food, capable of damaging the health of consumers, have been recorded frequently. In this study, 195 raw milk samples were obtained from Tangshan City, China, and the concentrations of 22 steroid hormones were measured by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Cortisol was detected in 12.5% of raw milk samples (mean 0.61 µg/kg; range:

Mutations in the tumor suppressor gene transforming growth factor beta (TGFB) Type II receptor (TGFBR2) are frequently found in many cancers with microsatellite instability, but are less common in lung cancer. In the present study, we looked for mutations in TGFBR2 in nonsmall cell lung carcinoma (NSCLC) cells and tissues. A novel homozygous microdeletion (c.492_507del) was identified in two cell lines derived from the same giant cell carcinoma (GCC) and was confirmed in the corresponding tumor tissues. Furthermore, a heterozygous c.492_507del was found in the germ-line of one patient, as well as in the other GCC cases and some large cell carcinomas (LCC) but not in other subtypes of NSCLC. The 16 bp-microdeletion introduced a premature stop codon at positions 590-592 of the cDNA, resulting in a truncated TGFBR2 protein with a mutated transmembrane domain and loss of kinase domain. The GCC cells were characterized as being unresponsive to TGFB induction both in growth inhibition and stimulation of extracellular matrix protein. Moreover, after the reconstitution of wild-type TGFBR2 expression, the sensitivity to TGFB was restored. Therefore, mutated TGFBR2 seems to play an important role in the abrogation of TGFB signal transduction in GCC cells.

This study evaluated chromium (Cr), arsenic (As), cadmium (Cd), and lead (Pb) contamination in raw milk from industrial areas in China, identified the possible pathways of heavy metals from the environment to raw milk, and made a risk assessment of the consumption of heavy metals from milk consumption. The Cr, As, Cd, and Pb concentrations in raw milk, water and silage were analyzed using inductively coupled plasma mass spectrometry. The Cr and As in soil were analyzed by flame atomic absorption spectrometry and atomic fluorescence spectrometry, respectively. Cd and Pb in soil were determined by a Graphite furnace atomic absorption spectrophotometer. The Cr and As concentrations in milk from industrial areas were 2.41 ± 2.12 and 0.44 ± 0.31 μg/kg, respectively, which were significantly higher (p < 0.01) than those from non-industrial areas, which had levels of 1.10 ± 0.15 and 0.25 ± 0.09 μg/kg, respectively. Chromium was mainly transferred through the soil-silage-milk pathway, As was transferred through the water-silage-milk pathway, while Cd was mainly transferred through the soil (water)-silage-milk pathway. The contributions of each metal to the overall hazard index (HI) followed a descending order of As, Cr, Pb, and Cd, with values of 46.64%, 25.54%, 24.30%, and 3.52%, respectively. Children were at higher risk than adults.

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