Skip to main content

Climate change can cause selenium deficiency in soil and humans (downtoearth,)

Predicting yet another implication of changing climate, a new study has claimed that human diet may be deficient of an essential micronutrient called selenium (Se) in the future. The report, published in journal Proceedings of the National Academy of Sciences, finds that quantity of the element will be depleted in soil, leading to lower uptake by plants and further, its reduction in our diet.

A team of researchers from Eawag, a research institute based in Switzerland, and five other institutes analysed already available data to model selenium concentration distribution globally. A total of 33,241 soil data points from 1980 to 1999 were used to look into the concentration of this micronutrient.

The team predicted the global Se-soil distributions scenario for 2080-2099. The overall effects are reduction of levels in Se in soil in most parts of the world. They also predict that it is likely that 66 per cent croplands will lose 8.7 per cent of their selenium amount.  These effects may be more pronounced in India and Europe. Both change in climate and soil carbon content dictate this forecast, according to researchers.

Two factors influence Se concentration in soil: precipitation and aridity index (denotes parched areas). Selenium gets leached out from soil due to precipitation. High Se concentrations are found in regions with high acidity and moderate precipitations, while low concentrations of the element are found in arid regions with high alkaline soil and low clay content. This was also established in earlier research.

Effects on health

Insufficient selenium intake is estimated to affect one billion people worldwide. Selenium is required to make antioxidants and prevent cellular damage in the body. Other symptoms of its deficiency include hypothyroidism, including extreme fatigue, mental slowing, goiter, mental retardation, and miscarriages. Exposure to high concentration of Se is also said to have detrimental effects to health.

Cases of a deadly heart ailment called Keshan disease, which has been linked to selenium, deficiency, were reported in northeast and southwest China in 1935. The condition was fatal in 40 per cent of the cases in 1940. When Se levels in the region were studied to investigate any link, it was found that Se concentration in maize and vegetables lower in endemic regions than non-endemic regions. The blood and hair samples from endemic population also showed low Se levels. However, researchers think there could be other factors like viral infection at play. Another study highlighted the role of Se in improving cardiac function after six months of treatment in a 15-month-old child from Saudi Arabia.

Selenium additives can be added to animal feed to avoid the ramifications of Se deficiency. Brazil nuts are rich in selenium and their consumption can reverse deficiency of the element.

Comments

Popular posts from this blog

Cloud seeding

Demonstrating the function of the flare rack that carries silver iodide for cloud-seeding through an aircraft. 
Water is essential for life on the earth. Precipitation from the skies is the only source for it. India and the rest of Asia are dependent on the monsoons for rains. While the South West Monsoon is the main source for India as a whole, Tamil Nadu and coastal areas of South Andhra Pradesh get the benefit of the North East Monsoon, which is just a less dependable beat on the reversal of the South West Monsoon winds.

SC asks Centre to strike a balance on Rohingya issue (.hindu)

Supreme Court orally indicates that the government should not deport Rohingya “now” as the Centre prevails over it to not record any such views in its formal order, citing “international ramifications”.

The Supreme Court on Friday came close to ordering the government not to deport the Rohingya.

It finally settled on merely observing that a balance should be struck between humanitarian concern for the community and the country's national security and economic interests.

The court was hearing a bunch of petitions, one filed by persons within the Rohingya community, against a proposed move to deport over 40,000 Rohingya refugees. A three-judge Bench, led by Chief Justice of India Dipak Misra, began by orally indicating that the government should not deport Rohingya “now”, but the government prevailed on the court to not pass any formal order, citing “international ramifications”. With this, the status quo continues even though the court gave the community liberty to approach it in …

Indian Polity Elections (MCQ )

1. Who of the following has the responsibility of the registration of voters
a) Individual voters
b) Government
c) Election commission
d) Corporations


2. Democracy exists in India, without peoples participation and co operation democracy will fail. This implies that
a) Government should compel people to participate and cooperate with it
b) People from the government
c) People should participate and cooperate with the government
d) India should opt for the presidential system


3. Which of the following are not the functions of the election commission
1) Conduct of election for the post of the speaker and the deputy speaker, Lok sabha and the deputy chairman, Rajya sabha
2) Conduct of elections to the state legislative assemblies
3) Deciding on all doubts and disputes arising out of elections

a) 1 and 2
b) 1 and 3
c) 2 and 3
d) 2

4. Which of the following electoral systems have not been adopted for various elections in India
1) System of direct elections on the basis of adult suffrage
2…