Effect of cadmium on the concentration of essential metals in a human chondrocyte micromass culture.

BACKGROUND: An essential element imbalance in the joint might favor gradual degeneration of the articular cartilage. It has been reported that cadmium (Cd) plays an antagonistic role with regards to the presence of essential elements, such as zinc (Zn), iron (Fe), and manganese (Mn), which may favor the development of disabling diseases, like osteoarthritis (OA) and osteoporosis. METHODS: 3D cultures of human chondrocytes were phenotyped with the Western blot technique and structurally evaluated with histological staining. The samples were exposed to 1, 5, and 10 µM of CdCl2 for 12 h, with a non-exposed culture as control. The concentration of Cd, Fe, Mn, Zn, chromium (Cr), and nickel (Ni) was quantified through plasma mass spectrometry (ICP-MS). The data were analyzed with a Kruskal Wallis test, a Kendall's Tau test and Spearman's correlation coefficient with the Stata program, version 14. RESULTS: Our results suggest that Cd exposure affects the structure of micromass cultures and plays an antagonistic role on the concentration of essential metals, such as Zn, Ni, Fe, Mn, and Cr. CONCLUSION: Cd exposure may be a risk factor for developing joint diseases like OA, as it can interfere with cartilage absorption of other essential elements that maintain cartilage homeostasis.

Assessment of nutrient contamination in the waters of the El Fuerte River, southern Gulf of California, Mexico.

This study assessed the spatial and temporal nutrient variability in the El Fuerte River basin in northwestern Mexico, considering its effects on the water trophic status as well as the nutrient loading to the Gulf of California. Physicochemical parameters, inorganic species of nitrogen, phosphate, total nitrogen, total phosphorus, and chlorophyll-a (chl-a) were quantified at 16 selected sites along the river in April (dry season) and October (rainy season) 2017. Mean concentrations of nutrients during dry and rainy seasons were 36.3 ± 24.1 and 55.1 ± 74.6 µg L-1 of total ammonia nitrogen, 3.4 ± 3.6 and 4.5 ± 3.5 µg L-1 of NO2--N, 190.8 ± 256.0 and 163.6 ± 261.0 µg L-1 of NO3--N, 42.4 ± 44.2 and 104.9 ± 76.2 µg L-1 of PO43--P, 1.0 ± 1.3 and 691 ± 2242 mg L-1 of TN, 0.06 ± 0.06 and 0.08 ± 0.09 mg L-1 of TP, and 0.9 ± 0.6 and 2.0 ± 0.9 µg L-1 of chl-a with significant differences (p < 0.05) between sites and seasons. When waters are transported downstream, nutrient levels are enriched by 4 to 35 times compared to those upstream due to increased population and agriculture downstream, confirming the hypothesis of the study. The calculated TN and TP fluxes were 1.23 × 104 and 3.57 × 101 ton year-1, respectively. Factor analysis indicated that inorganic nitrogen species and phosphorus are the main factors affecting the river water quality. Despite N excess during the rainy season, the river reached mesotrophic waters due to phosphorus limitation. This suggests the need to establish a water quality monitoring program to understand the vulnerability of the river course to changes in its trophic state.

Environmental exposure to chromium compounds in the valley of León, México.

The effects on the environment and health of the operation of a chromate compounds factory and tanneries in the León valley in central México are discussed. Sampling and analysis of chromium were performed in water, soil, and human urine. Groundwater has been polluted in an area of about 5 km2 by the leaching of a solid factory waste, which results in concentrations up to 50 mg/l of hexavalent chromium. The plume shape and extension appear to be controlled by the prevailing well extraction regime. Total chromium was detected in the soil around the factory as a result of both aerial transport and deposition of dust produced in the chromate process and irrigation with tannery-contaminated water. Analysis of the impact of chromium in air and water on populations with various degrees of exposure revealed that highly harmful health effects were not observed.