Science & Tech Current Affairs

Science & Technology Current Affairs 2019-2020 category comprises current affairs with all important national / international updates in science and tech and events for the year 2019-2020 for UPSC, States, Civil services, SSC and other competitive examinations of India and States.

Ammonium Nitrate: The Beirut Explosion

A catastrophic blast occurred recently at the Lebanon capital, Beirut. The blast was driven by tonnes of Ammonium Nitrate that killed more than 135 people. Also, it injured more than 1000s.

Ammonium Nitrate

Ammonium Nitrate is a white, crystalline chemical that is soluble in water. It is the main ingredient used to manufacture commercial explosives


In India, the use of Ammonium Nitrate is defined by the Ammonium Nitrate Rules, 2012 under the Explosives Act, 1884. According to the rules, it is a compound that has more than 45% of ammonium nitrate by weight. This includes suspensions, emulsions, gels or melts excluding fertilizers, slurry explosives and non-explosive emulsion matrix.

The rules also make the storage of large quantities of ammonium nitrate illegal. In order to manufacture Ammonium Nitrate in India, industrial license is required under Industrial Development and Regulation Act, 1951.

United Nations Classification of Dangerous Goods

Under the UN classification of dangerous goods, ammonium nitrate is classified as an oxidiser. However, it can be used as an explosive when mixed with other contaminants.

As an Explosive

The Improvised Explosive Devices used by terrorists in the world contain Ammonium Nitrate Fuel Oil (ANFO). Ammonium Nitrate when used as with RDX or TNT can create catastrophic effects. In majority of terror attacks in India in places such as Varanasi, Pulwama, Pune, Malegaon, Delhi, Mumbai and Hyderabad, ammonium nitrate is used with the initiator RDX.

Ammonium Nitrate: Major Fire Hazard

The explosion of ammonium nitrate can happen in two ways. One, when the stored chemical comes in contact and the other is due to fire that starts due to extensive oxidation process. The Beirut explosion is due to oxidation at large scale.

Previous Incidents

In 1921, around 4,500 tonnes of Ammonium Nitrate exploded in Oppau, Germany that killed 500 people. In 1947, around 2,000 tonnes of ammonium nitrate detonated at Galveston Bay, Texas killing 581 people. In 2015, an explosion due to Ammonium nitrate killed 173 people in Tianjin port, China.

First Mobile RT-PCR lab of India developed by IISc launched in Karnataka

On August 5, 2020, the State Government of Karnataka launched India’s first mobile RT-PCR lab in Bengaluru. The lab was developed by Indian Institute of Science, Bengaluru. The lab has been named Mobile Infection Testing and Reporting (MITR) lab. It is capable of conducting 9000 tests per month.

About the lab

Apart from testing COVID-19, the lab can also be utilised to test HCV, H1N1, TB, HIV, HPV, etc. The main advantage of the lab is that it can be used for molecular diagnostic testing in COVID-19 hotspots quickly.


The RT-PCR is the Reverse Transcription Polymerase Chain Reaction. The test mainly measures the amount of a specific RNA. During the test, RNA is converted into complementary DNA using the enzyme reverse transcriptase.

COVID-19 testing

The COVID-19 testing assesses the current or past presence of SARS-COV-2 virus. There are two branches in the testing namely detecting the presence of virus or antibodies. The test that involves detecting the virus is used to diagnose individual cases. This helps public health authorities to trace and contain the outbreak. On the other hand, the antibody testing shows if a person has had the disease earlier. This is useful in asses disease prevalence and estimate infection fatality rate.

Other COVID-19 testing

Apart from RT-PCR, there are several other COVID-19 testing methodologies used. They are as follows

Isothermal Amplification Assays

It is an Isothermal nucleic acid amplification testing methodology that is used to amplify genome of the virus. It is faster than RT-PCR as it does not involve repeated cooling and heating cycles.

Antigen Testing

The antigen testing of COVID-19 looks for proteins in the viral surfaces. In case of COVID-19, the antigen testing looks for the surface spikes.


These are blood tests that are used to identify antibodies such as IgM and IgG. These antibodies are generated as an immune response by the human body against COVID-19.

The other COVID-19 tests used are as follows

  • Rapid Diagnostic Test
  • Enzyme-linked Immunosorbent Assay (ELISA)
  • Neutralization Assay
  • Chemiluminescent Immunoassay.