Air pollution and cardiac arrhythmias: what you need to know



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Air pollution and cardiac arrhythmias: what you need to know

The study published on the Current problems in cardiology, Air Pollution and Cardiac Arrhythmias: A Comprehensive Review, gives an interesting retrospective on this situation that could be having a relationship. The study tells us how air pollution is the mixture of some chemical and environmental agents including dust, fumes, gases, particulate matters, and biological materials which can be harmful for the environment and the human body.

The increasing trend of the air pollution, especially in developing countries, may exert its detrimental effects on human health. The potentially harmful effects of air pollution on the human health have been recognized and many epidemiological studies have clearly suggested the strong association between air pollution exposure and increased morbidities and mortalities.

Air pollutants are classified into gaseous pollutants including carbon mono oxide, nitrogen oxides, ozone and sulfur dioxide, and particulate matters (PMs). All air pollutants have destructive effects on the health systems including cardiovascular system.

Many studies have demonstrated the effect of air pollutant on the occurrence of ST elevation myocardial infarction, sudden cardiac death, cardiac arrythmias, and peripheral arterial disease. Recently, some studies suggested that air pollution may be associated with cardiac arrhythmias.

In this study, we aimed to comprehensively review the last evidences related to the association of air pollutant and cardiac arrythmias. We found that particulate matters (PM10, PM2.5, and UFP) and gaseous air pollutants can exert undesirable effects on cardiac rhythms.

Short-term and long-term exposure to the air pollutants can interact with the cardiac rhythms through oxidative stress, autonomic dysfunction, coagulation dysfunction, and inflammation. It seems that particulate matters, especially PM2.5 have stronger association with cardiac arrhythmias among all air pollutants.

However, future studies are needed to confirm these results.

Brine shrimp of Great Salt Lake drowned in mercury and selenium?

The Great Salt Lake is what remains of Lake Bonneville today, a vast prehistoric basin that has largely dried up.

The lake is located at an average altitude of 1,280 m. It has a length of about 120 km and a width that varies between 48 km and 80 km. The average surface area of ​​the lake is 4,400 km², which makes it the second largest lake among those entirely within the borders of the United States, after Lake Michigan, and is subject to strong seasonal variations.

The lake is on average shallow, about 4.5 m. The waters of the Great Salt Lake have a chemical composition very similar to that of ocean waters. The saline concentration varies between 50 g / l and 270 g / l. Due to the high salinity, few living species are able to inhabit it.

The most representative species is constituted by the small crustaceans of the Artemia salina (brin shrimp) species. In summer, the lake attracts tourists and local people, who go there to swim, similar to what happens in the Dead Sea.

The study: Temporal correspondence of selenium and mercury, among brine shrimp and water in Great Salt Lake, Utah, USA, seeks to evaluate the risks that can jeopardize the survival of brine shrimp, in an environment that could be polluted by agents such as precisely selenium and mercury.

Published on the The Science of the total environment, we can read: "The specific source of high burdens of selenium (Se) and mercury (Hg) in several bird species at Great Salt Lake (GSL) remain unknown. Frequent co-located water and brine shrimp samples were collected during 2016 through 2017 to identify potential correlations of element concentrations among brines and brine shrimp, a keystone species in the GSL.

Like many aquatic systems, GSL is characterized by elevated methylmercury (MeHg) in deep waters. in contrast to thermally-stratified aquatic systems, biota in the salinity-stratified GSL do not reside in its deep waters, obscuring the presumed relationship between elevated MeHg in biota and in the deep brine.

Brine shrimp and water column (shallow and deep, filtered and unfiltered) samples were collected from six sites spanning the South Arm of GSL approximately every other month. Mercury concentrations in brine shrimp (on average 89% of which is MeHg) were correlat ed only with total mercury in surface filtered water, and displayed little spatial variability, but consistent seasonal trends across the two sampled years.

In contrast to Hg, temporal correspondence was observed between Se concentrations in brine shrimp and those in all water samples regardless of filtering and depth, with maxima and minima at higher-than-seasonal frequency.

The data suggest a spatially diffuse source of bioavailable mercury to the shallow brine that responds to seasonal influences, for which the underlying deep brine, surficial sediments, and overlying atmosphere were evaluated in terms of potential temporal correspondence to shallow brine and brine shrimp Hg concentrations, as well as potential to mix across the extent of the shallow brine.

Bioaccumulation factors were at the low end of those reported for marine systems, and decreased at higher trace element concentrations in water. "