Daily BulletinDaily Bulletin

The Conversation

  • Written by The Conversation
imageReuters/CDIC

Officials investigating a huge explosion at a warehouse in Tianjin in China have discovered a store of 700 tonnes of sodium cyanide – more than 70 times the legal limit allowed. Cyanide has a particularly unpleasant reputation and finding it at a major disaster site is far from welcome. However, if officials act fast they should be able to limit its damaging effects.

What is sodium cyanide?

The term cyanide is clearly understood in the public consciousness to be almost synonymous with poison itself. This is largely because of its use as lethal suicide pill (L-pill) in World War 2, most notably with the suicide of Nazi army officer Erwin Rommel. The cyanide used in the L-pill was potassium cyanide but the properties of sodium cyanide are nearly identical.

An inorganic and very innocent looking white solid with deadly properties, sodium cyanide (NaCN) can be fatal at amounts as little as 5% of a teaspoon. It is produced from the equally dangerous gas hydrogen cyanide (HCN) in a simple process with sodium hydroxide.

Why would a company want so much of it?

Sodium cyanide is used industrially across the globe, most frequently in the mining of gold. Although most of us have the traditional imagery of a 19th-century gold miner panning for nuggets, this isn’t the industrial method used today.

Most of the world’s gold is not found in nugget form but as very fine gold powders in rocks. In fact, our cultural demand for gold forces us to mine in rocks that can be as low as 0.005% gold. This means we need industrial extraction to separate and purify gold from all the other materials.

After mining and milling, the crude rock mixture is turned into a fine powder and added to a solution of sodium cyanide. The gold forms strong bonds with cyanide molecules and can then be separated from the rest of the minerals because it is then soluble in water. It then reacts with zinc and turns back into a solid. Finally is smelted to isolate the gold and cast into bars.

imageDeadly smokeReuters/China Stringer Network

How dangerous is it?

As with the very similar potassium cyanide used in the L-pill, sodium cyanide is extremely toxic to humans. Although there are risks with skin absorption, the biggest risk is ingestion. Inhaling or swallowing sodium cyanide blocks oxygen transport causing serious medical problems and ultimately death.

However, the safety of sodium cyanide changes if it is present during an explosion. Avoiding oral ingestion should usually be relatively simple but an explosion can cause it to be inhaled as a fine powder (this danger should have passed quickly – and face masks will also prevent fine powder inhalation). The biggest fear is the formation of hydrogen cyanide upon exposure to water or high temperatures. Hydrogen cyanide, as a gas, is very dangerous if inhaled.

What if the remaining store leaks?

Contamination of water supplies could be a concern but is easily tested for. The Chinese authorities seem to be treating the spill with hydrogen peroxide, which forms significantly less dangerous fulminates. Waste water and other areas could be simply treated with sodium hypochlorate (bleach) to remove cyanide ions.

The spill is (but more significantly was) very dangerous, especially at these levels. But the nature of cyanides means we can detect them easily and monitor the process of cleaning up. The clean-up should proceed as quickly as possible. The other heartening factor is that after the short-term – albeit very seriously deadly – effects, there should be no slow-onset ramifications, as you would get with a carcinogen or something harder to deal with.

All previous spills have been dealt with easily with no long-term effects and the procedures are well known, so all the hydrogen cyanide in Tianjin should now be gone. The solid sodium cyanide is not so dangerous in passing: you can open a bottle with 3,000 times the lethal dose without any problems (without letting it react with moisture and convert to hydrogen cyanide). The advice for anyone nearby would be to avoid drinking the contaminated water and stay out of the area while the hydrogen cyanide is processed by natural biochemical pathways and climate dilution to safe levels.

Benjamin Burke does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond the academic appointment above.

Authors: The Conversation

Read more http://theconversation.com/explainer-how-dangerous-is-the-sodium-cyanide-found-at-tianjin-explosion-site-46229

Don't rush into a hydrogen economy until we know all the risks to our climate

arrow_forward

Pastel colours and serif fonts: is Annastacia Palaszczuk trying to be an Instagram influencer?

arrow_forward

Are there ‘male’ and ‘female’ brains? Computers can see a distinction, but they rely strongly on differences in head size

arrow_forward

The Conversation
INTERWEBS DIGITAL AGENCY

Politics

Did BLM Really Change the US Police Work?

The Black Lives Matter (BLM) movement has proven that the power of the state rests in the hands of the people it governs. Following the death of 46-year-old black American George Floyd in a case of ...

a Guest Writer - avatar a Guest Writer

Scott Morrison: the right man at the right time

Australia is not at war with another nation or ideology in August 2020 but the nation is in conflict. There are serious threats from China and there are many challenges flowing from the pandemic tha...

Greg Rogers - avatar Greg Rogers

Prime Minister National Cabinet Statement

The National Cabinet met today to discuss Australia’s COVID-19 response, the Victoria outbreak, easing restrictions, helping Australians prepare to go back to work in a COVID-safe environment an...

Scott Morrison - avatar Scott Morrison

Business News

Reinventing The Outside Of Your Office

Efficient work is a priority in most offices. You need a comfortable interior that is functional too. The exterior also affects morale. Big companies have an amazing exterior like university ca...

News Company - avatar News Company

Kaspersky and Ferrari partnership: tailoring cybersecurity for an iconic brand

Kaspersky is commemorating the 10 year anniversary of its strategic partnership with iconic, global brand - Ferrari. The cybersecurity company is a sponsor of the brand’s Formula One racing team...

News Company - avatar News Company

Instant Steel Solutions Review

Are you keen on having the right guidance, knowledge and information about the right kind of steel purchases for your industries? If yes, then you are in the right place. There is no doubt that ...

a Guest Writer - avatar a Guest Writer



News Company Media Core

Content & Technology Connecting Global Audiences

More Information - Less Opinion