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- Using cattle hair to assess exposure to essential trace elements in volcanic soilsPublication . Linhares, Diana; Garcia, Patrícia; Pimentel, Adriano; Gaspar, Diogo; Rodrigues, Armindo dos SantosBackground In areas where cattle graze outdoors, the environmental availability of trace elements is of utmost importance for an adequate intake. Cattle hair trace elements can be used as exposure biomarkers to assess animal intake and help ensure good nutrition and animal welfare. The aim of this study was to evaluate the environmental exposure to trace elements in cattle grazing outdoors in a volcanic region (São Miguel Island, Azores) and assess the corresponding bioaccumulation factors. Methods Twenty-nine samples of pasture topsoil were collected in two areas of São Miguel with different geological characteristics: Picos fissure system (basaltic area) and Povoação volcano (trachytic area). Hair from fifty-four animals (calves and dairy cows) was collected in two grazing sites: Ponta Delgada (Picos fissure system) and Povoação (Povoação volcano). All samples were analysed by inductively coupled plasma mass spectrometry (ICP-MS) after digestion in aqua regia. Results Basaltic soils of the Picos fissure system had significantly higher concentrations of most trace elements, except Mo, when compared with the trachytic soils of Povoação volcano. Hair of calves from Povoação showed higher concentrations of most essential trace elements, except Mg, Cu, and Zn, than hair from calves of Ponta Delgada (considered in this study as a control group since they are raised in a barn). On the other hand, hair from dairy cows grazing in Ponta Delgada showed higher concentrations of most essential trace elements, except Mg, As, and Mo, when compared with hair of cows grazing in Povoação. Conclusions Cattle hair trace elements are suitable biomarkers for the assessment of the environmental exposure to trace elements in volcanic soils. The results from dairy cows support the uneven distribution of essential trace elements (and their bioavailability) in the different soils of São Miguel, reinforcing the need to graze animals outdoors from an early age. Such practice (grazing cattle outdoors) provides another means of accessing essential trace elements that complemented with feed can reduce the natural depletion of these essential elements in the body due to reproductive phenomena and milk production.
- Fluoride levels in water sources inside the crater of Furnas volcano: Potential health implications for local communities and touristsPublication . Linhares, Diana; Gaspar, Diogo; Bernardo, Filipe; Beney, Isabelle; Garcia, Patrícia; dos Santos Rodrigues, ArmindoABSTRACT: Fluoride, a naturally occurring mineral, is widely recognized for its dual role in human health. At optimal concentrations, it provides dental benefits; however, excessive fluoride can lead to dental and skeletal fluorosis. Volcanic regions are known for their geothermal water sources that contain elevated levels of fluoride, raising concerns about potential health impacts on local populations. This study focuses on the Furnas volcano region at the Island of São Miguel, Azores, where natural springs are promoted for their therapeutic and medicinal properties. However, these springs also raise concerns about health risks due to fluoride exposure, as they are freely consumed by locals and tourists without any formal treatment or monitoring. Eighteen water samples were collected from natural springs in the village of Furnas. In situ measurements were taken forphysicochemical parameters such as pH, temperature, and conductivity. Fluoride concentrations were quantified using a potentiometric method with a fluoride ion-selective electrode. To assess risks, we estimated daily fluoride intake (DFI) and calculated the Hazard Quotient (HQ) for both children and adults. The fluoride concentrations in the samples ranged from 0.47 mg/L to 5.48 mg/L, with 72 % exceeding the recommended limit of 1.5 mg/L for drinking water. Significant correlations were found between temperature, conductivity, and fluoride concentration. Hazard Quotient values indicated potential health risks for children consuming untreated spring water. Waters categorized as hypothermal exhibited significantly lower fluoride concentrations compared to mesothermal, thermal, and hyperthermal samples. These findings highlight the impact of volcanic activity on fluoride levels in the natural springs of Furnas, emphasizing the need for regular monitoring and public awareness. While these waters are frequently consumed for their perceived health benefits, elevated fluoride levels may pose health risks to residents and tourists, demanding informed decision-making and enhanced water safety measures.