Arsenic in Lake Geneva (Switzerland, France): long term monitoring, and redox and methylation speciation in an As unpolluted, oligo-mesotrophic lake

Association between urinary heavy metal/trace element concentrations and kidney function: a prospective study

Background

Chronic kidney disease (CKD) is an important public health problem. Although cross-sectional studies have identified many heavy metals/trace elements associated with reduced kidney function, prospective studies are needed to determine the pathogenic role of these elements in the development and progression of CKD.

Methods

To explore the association between baseline urinary heavy metal/trace element concentrations and long-term impaired kidney function (IKF)/CKD, as well as the incidence of rapid decline in kidney function in a population-based exploratory prospective study, with mean age 51.9 years at baseline whose urinary trace elements concentrations have been determined by inductively coupled plasma mass spectrometry. IKF was defined by a reduced estimated glomerular filtration rate (eGFR) between 60 and 90 mL/min/1.73 m2, and CKD was defined as an eGFR <60 mL/min/1.73 m2. Rapid eGFR decline was defined as a decrease ≥3 mL/min/1.73 m2/year.

Results

Over a mean follow-up of 12.5 years, 123 participants (2.6%) experienced rapid decline in kidney function, and 1455 (31.7%) developed IKF or CKD. After adjusting for covariates including baseline eGFR, we found that urinary vanadium [hazard ratio (HR) = 1.07, 1.03-1.12], cobalt (HR = 1.69, 1.21-2.37), nickel (HR = 1.19, 1.08-1.3), copper (HR = 1.03, 1.01-1.06), selenium (HR = 1.33, 1.02-1.73), molybdenum (HR = 1.48, 1.2-1.82) and iodine (HR = 1.1, 1.02-1.2) were associated with an increased risk of new incident IKF or CKD cases during the follow-up. Also, urinary copper [odds ratio (OR) = 1.12, 1.04-1.21], silver (OR = 1.83, 1-3.35), molybdenum (OR = 1.02, 1.01-1.04) and cadmium (OR = 1.05, 1.01-1.09) were associated with an increased risk of rapid eGFR decline.

Conclusion

In the general population, several urinary heavy metals/trace elements are associated with a rapid decline in kidney function or new cases of IKF/CKD.

Distribution, seasonal variation and influencing factors of total dissolved inorganic arsenic in the middle and lower reaches of the Yellow River

The concentrations of dissolved arsenate in natural water has an important impact on human health. The distributions, seasonal variation and major influencing factors of total dissolved inorganic arsenic (TDIAs) were studied in the Yellow River. The concentrations of TDIAs in the middle and lower reaches of the Yellow River ranged from 4.3 to 42.4 nmol/L, which met the standards for drinking water of WHO. The seasonal variation of TDIAs concentration in the middle and lower reaches of the Yellow River was highest in summer, followed by autumn and winter, and lowest in spring. The influencing factors of TDIAs concentration in the middle and lower reaches of the Yellow River mainly include the hydrological conditions, topographical variation, the adsorption and desorption of suspended particulate matter (SPM) and the intervention of human activities. The absorption of TDIAs by phytoplankton in the Xiaolangdi Reservoir (XLD) is an important factor affecting its distributions and seasonal variation. The annual flux of TDIAs transported from the Yellow River into the Bohai Sea ranged from 1.1 × 105 to 4.5 × 105 mol from 2016 to 2018, which is lower than the flux in 1985 and 2009. The carcinogenic risks (CR) of TDIAs for children and adults were all within acceptable levels (<10-6).