As and [Formula: see text] cooccurrence in drinking water: critical review of the international scenario, physicochemical behavior, removal technologies, health effects, and future trends

Testicular protective effects of hesperidin against chemical and biological toxicants

Toxic agents can adversely impact the male reproductive system mainly via activating oxidative stress affecting the seminiferous epithelia, spermatogenesis, sperms, and the testis. Toxic agents lead to the excessive generation of reactive oxygen species (ROS), such as hydroxyl radicals, hydrogen peroxide, and superoxide anions. ROS exert a cytotoxic effect and oxidative damage to nucleic acids, proteins, and membrane lipids. Hesperidin is a pharmacologically active phytoflavone abundantly occurring in citrus fruits, such as oranges and lemons. It has shown various pharmacological properties such as antioxidant, anti-inflammatory, anti-carcinogenic, analgesic, antiviral, anti-coagulant, hypolipidemic, and hypoglycemic effects. Hesperidin has been found to exert protective effects against natural and chemical toxins-induced organ toxicity. Considerable evidence has implicated the testicular protective effects of hesperidin against the toxicological properties of pharmaceutical drugs as well as biological and chemical agents, and in the present review, we discussed, for the first time, the reported studies. The resultant data indicate that hesperidin can exert testicular protective effects through antioxidant properties.

In vitro and in vivo approaches to assess atherosclerosis following exposure to low-dose mixtures of arsenic and cadmium

Worldwide, millions of people are co-exposed to arsenic and cadmium. Environmental exposure to both metals is linked with a higher risk of atherosclerosis. While studies have characterized the pro-atherosclerotic effects of arsenic and cadmium as single agents, little is known about the potential effects of metal mixtures, particularly at low doses. Here, we used a combination of in vitro and in vivo models to assess the effects of low-dose metals individually and as mixtures on early events and plaque development associated with atherosclerosis. In vitro, we investigated early pro-atherogenic changes in macrophages and endothelial cells with metal treatments. The combined cytotoxic effects of both metals at low concentrations were dose interactive, specifically, synergistic in macrophages, but antagonistic in endothelial cells. Despite this differential behavior across cell types, the mixtures did not initiate early pro-atherogenic events: neither reactive oxygen species generation in macrophages nor adhesion molecule expression on endothelial cells. In vivo, we utilized the well-characterized hyperlipidemic apolipoprotein E knock-out (ApoE-/-) mouse model. Previously, we have shown that low concentrations of arsenic (down to 10 ppb) enhance atherosclerosis in ApoE-/- mice. This model has also been used with cadmium to demonstrate pro-atherogenic effects, although at concentrations above human-relevant exposures. In both sexes, there are some small increases in atherosclerotic lesion size, but very few changes in plaque constituents in the ApoE-/- mouse model. Together, these results suggests that low-dose metal mixtures are not significantly more pro-atherogenic than either metal alone.

Geochemical control, water quality indexing, source distribution, and potential health risk of fluoride and arsenic in groundwater: Occurrence, sources apportionment, and positive matrix factorization model

Fluoride (F-), and arsenic (As) in the groundwater cause health problems in developing countries, including Pakistan. We evaluated the occurrence, distribution, sources apportionment, and health hazards of F-, and As in the groundwater of Mardan, Pakistan. Therefore, groundwater samples (n = 130) were collected and then analyzed for F-, and As by ion-chromatography (IC) and Inductively-coupled plasma mass-spectrometry (ICP-MS). The F-, and As concentrations in groundwater were 0.7-14.4 mg/L and 0.5-11.2 µg/L. Relatively elevated F-, and As coexists with higher pH, Na+, HCO3-, SO4-2, and depleted Ca+2 due to fluoride, sulfide-bearing minerals, and anthropogenic inputs. Both F-, and/or As are transported in subsurface water through adsorption and desorption processes. Groundwater samples 45%, and 14.2% exceeded the WHO guidelines of 1.5 mg/L and 10 µg/L. Water quality indexing (WQI-model) declared that 35.7% samples are unfit for household purposes. Saturation and undersaturation of minerals showed precipitation and mineral dissolution. Groundwater contamination by PCA-MLR and PMF-model interpreted five factors. The fitting results and R2 values of PMF (0.52-0.99)>PCA-MLR (0.50-0.95) showed high accuracy of PMF-model. Human health risk assessment (HHRA-model) revealed high non-carcinogenic and carcinogenic risk for children than adults. The percentile recovery of F- and As was recorded 98%, and 95% with reproducibility ± 5% error.

Trace elements in aquatic products from Shenzhen, China and their implications for human exposure

Aquatic organisms in industrially polluted areas can accumulate large quantities of heavy metals. To assess the resulting health risks, 11 trace elements in 184 aquatic products representing 14 species of fish, crustaceans, and bivalves collected from Shenzhen, China were determined. Aluminum (Al), chromium (Cr), nickel (Ni), selenium (Se), antimony (Sb), manganese (Mn), copper (Cu), arsenic (As), cadmium (Cd), mercury (Hg), and lead (Pb) were determined by inductively coupled plasma mass spectrometry. The pollution levels of each product and the human health risk resulting from their consumption were then assessed. The concentrations of As in 57 % of samples and Cd in 11 % of samples exceeded the upper limits stipulated by the Chinese National Food Safety Standards (GB 2762-2017), which was mainly due to high concentrations of trace elements in crustaceans and bivalves. The Nemerow integrated pollution index indicated that the aquatic products accumulated high levels of As and Cd. Health risk assessments using the target hazard quotient (THQ) and hazard index (HI) suggested that As and Cd exposure due to consumption of aquatic products presents a potential health risk for residents of Shenzhen.