Cadmium, simple test for?

[Paul FallertParticipant @paulfallert28101]

Does anyone know of a simple test for cadmium?

 

Background: Cadmium was at one time used to plate workshop tools. Cadmium plated tools may be present today in our workshops. Cadmium is very toxic and can be absorbed through the skin or oxides of cadmium can be absorbed through the lungs when heated. Worse, cadmium metal may be found among the scraps. It is best avoided because exposure accumulates in the kidneys and liver. Cadmium has been removed from most silver solder due to this toxicity.

 

I was reminded of this subject while readying the current MEW where a simple test was offered for the presence of magnesium (a drop of vinegar causes fizzing of magnesium) so it can be avoided when melting aluminum. A bar of cadmium could be mistaken for aluminum.

[Paul FallertParticipant @paulfallert28101]

Cadmium plating was used for some tools

[David LittlewoodParticipant @davidlittlewood51847]

A Google search shows there are test kits available, for example here

 

David

[Paul FallertParticipant @paulfallert28101]

David: Thank you for the reference to the commercial test kit, but I was hoping for something that might be readily available when (and if) the need arose.

 

Most of us will not be willing to buy something that we are not sure we will need. The vinegar test for magnesium is ideal because it is inexpensive and readily available when/if needed.

 

Does anyone know of a simple test that is readily available and inexpensive?

 

Paul

[Sub MandrelParticipant @submandrel]

Cadmium plated stuff should be easy to spot because of it’s dull blue-grey mealy appearance. You probably have some old Cd passivated screws in your bits boxes.

 

I’d be surprised to find a lump of cadmium in my scrap bin though.

 

Neil

[Paul FallertParticipant @paulfallert28101]

Neil:

I was thinking of finding a lump of cadmium at the scrap metal yard among the aluminum bits.

Paul

[Swarf, Mostly!Participant @swarfmostly]

Hi there, all,

 

I haven’t personally encountered cadmium plated workshop tools (that’s not a denial that they exist).

However, when I started in the electronics industry ‘cadmium plate & passivate’ was a standard treatment for the equipment chassis, panels and brackets made from mild steel as well as fastenings and spacing pillars. I remember it as being a light greenish-yellow colour rather than blue-grey. Maybe the final colour was dependent on the passivation dip?

I seem to remember also encountering it on the soft iron parts of relays and contactors.

When it corrodes in damp conditions, it can form a white powdery coating – contact with this would pose a risk of assimilation. (Now wash your hands, please!)

The plating shop used to use anodes comprising a metal basket into which they loaded spherical lumps of cadmium metal, about the size of a tennis ball. I have seen one of those lumps offered for sale on eBay.

Cadmium plating has been phased out and replaced by bright zinc plating (aka ‘BZP’). However, as Neil has written, I guess many of us will have lots of Cd plated fastenings in our ‘come in handy’ boxes or racks of 2 oz. tobacco tins.

 

 

Best regards,

 

Swarf, mostly.

[Paul FallertParticipant @paulfallert28101]

A worker using an oxyacetylene torch and silver solder containing cadmium was overcome with acute pneumonia and died 5 days later. (Lucas: 1980)

[Les Jones 1Participant @lesjones1]

Hi Paul,

You will not confuse a lump cadmium with a lump of aluminium.

The density of cadmium is 8.65 g/cc The density of aluminium is 2.7 g/cc It would weigh over three times the weight of a piece of aluminium of the same size. I also think it very unlikely you would find a solid lump of cadmium.

 

Les.

[Engine BuilderParticipant @enginebuilder]

When I was at school in the 60s we did cadmium plating in the metalwork class!

I recall there was a large tank of liquid involved I think cyanide was used. The metalwork teacher showed us a bottle of some thick liquid that was kept above it and we had instruction to drink it if we fell in or something!

How times have changed.

David

[Charlie,Participant @charlie18171]

Dont they still use large lumps of cadmium as anodes to prohibit rust on steel hulls

of ships ?

[Ian S CParticipant @iansc]

Charlie, that would work, but the metal used is normally zinc, aluminium is also used at a fraction of the cost of cadmium. Ian S C

[SpringbokParticipant @springbok]

Sacrificial anodes a usualy zinc and are welded to the hull this causes the electrical charge that is around the hull to be attracted to the anode and not erode the hull.

These can be purchased in any ships chandelers. they are also used on fibreglass hulls to prevent osmosis.

David that school lab sounds a bit hairy….

The only cadmium that I have been aware of in the workshop is silver solder and that is being phased out (I believe this month) and it will be illegal to sell it. Check the Cup Alloys site. the consequence being there has to be a higher content of silver and more expensive rods.

 

Bob

[Clive HartlandParticipant @clivehartland94829]

I spent 6 months in a plating shop as part of my army apprenticeship.

cadmium plating is now not used commercially but is still used on aircraft components.

The passivation will turn it a goldy yellow colour.

Mainly we plated the links and hammer bars on Creed Teleprinters with it.

It has a pleasant colour to look at but as said it is deadly over time.

 

Clive

 

[Ian S CParticipant @iansc]

Just mislayed it at the moment, but I have a hand book for teachers, NZ education, from the 1960s, and Cadmium plating was one, along with copper and nickel, the only worry in the book was the hazard of acid, and cyanide. The kids were tougher in those days..perhaps.

Ian S C

[KWILParticipant @kwil]

Whilst I agree cadmium is a largely undesireable material, I fear we have been talked into a rather fanatical approach to the subject. Same goes for so called long life efficient lamps, they really contain some nasties and nobody says a thing about it.

 

A worked died at Lucas in 1980, cadmium related? Many, many more die and continue to die from drink, but they have not banned alchohol !!!!

[Clive HartlandParticipant @clivehartland94829]

The way chemicals get into the human system and the effects apart from death are interesting.

When I was in kenya we often visited the taxidermist works, the name was Zimmermans.

A nicer chap you have never met, he took a shine to my wife and took us around to see the processes being carried out and also gave my wife a piece of Leopard fur to keep.

While talking he said that the cyanide had got into his system and showed us his hair which had turned green!

He had been exposed to it for years. He said if a snake bit him it would die first.

The store shed reeked of strong chemical and I could not go in without choking and coughing.

 

Clive

[magpieParticipant @magpie]

When i was an apprentice in Rolls Royce ( car Div. ), all the nuts & bolts Etc. were cadmium plated, and came with a thick coating of grease. I often had to go and degrease these in a large Tric tank, i remember being high as a kite after 10 mins doing that. Still here at age 71 so not too much damage !!!!!!! I think !!!!!

 

Cheers Derek

[Alex gibsonParticipant @alexgibson50133]

I don’t think we should be too worried about cadmium poisoning. Let’s face it, most of us don’t buy green bananas these days.

 

regards

alex

[Hugh GilhespieParticipant @hughgilhespie56163]

To answer Paul’s question. Test, yes, simple -no. Details here.http://pubs.acs.org/doi/abs/10.1021/i560126a027

 

Regards, Hugh

[peter walton 1Participant @peterwalton1]

Just been trawling the web for any answers to this question and stumbled on something I had never thought of.

It would appear that Cadmium is sometimes added to Gold to make jewellry which could answer something that has had me puzzled for some time, in that some people are allergic to Gold jewellry which I always thought was non toxic.

As to the OP question , I dont think there is a simple test for Cd.

peter

[Nicholas FarrParticipant @nicholasfarr14254]

Hi Peter, you can be/become allergic to anything at any time in your life, I don’t believe toxicity has much direct connection with being allergic to anything, after all some foods which have no toxins in are allergic to some people. Toxins will make just about anyone ill or have a fatal outcome, either in a short or long term.

 

Regards Nick.

[Billy MillsParticipant @billymills]

Very low level long term exposure can cause tolerance to develop to substances that are lethal in small doses but sometimes low level long term exposure can also lead to sensitisation to other substances, it is a very complex issue.

A very interesting study of the animals living around Chernobyl has shown that long term exposure to radiation levels way above normal limits has not lead to the expected DNA defects but to the development of a remarkable resistance to ionising radiation. Another major benefit to these animals has been the almost total exclusion of man.

 

Allergic reaction and food intolerance was just not around decades ago, either a very large proportion of the population has been sensitised or we did not recognise the problems.

 

I did A level Chemistry semi micro anl 40 years ago. I think the Cd test used dilute Hydrochloric acid to put the metal into solution then Hydrogen Sulphide gas was bubbled through to create a precipitate which was then nitrated then conc Sulphuric was used to produce a yellow precipitate, could be a bit out after 40 years. Not the sort of test easily done at home. The flame colour was light blue but you would not want to do that these days unless you were certificated insane.

 

Many of the nasty heavy metals tend to form insoluble white carbonates when weathered which is why lead pipes are not that dangerous.

 

Billy.

 

 

[Mark P.Participant @markp]

I really wouldn’t worry about cadmium,I for one will not loose any sleep over it. We are constantly bombarded with health and safety & food scares we are loosing sight of reality,eat more lard I say!

 

Pailo.

[Paul FallertParticipant @paulfallert28101]

Pailo:

The medical case (Lucas, 1980) mentioned above brought the issue to my attention by a friend.

 

The welder in that case only worked for 30 minutes with his (notably) high temperature torch on the silver soldering project. That’s all it took to kill him. The silver solder only contained a minute amount of cadmium, but it was vaporized by the torch and he inhaled the fumes. Some are more susceptible than others to toxics.

 

One of our famous posters claims to down several pints per day and he’s still with us ( I think )…come to thing of it, he has not posted for a while. I hope he is OK.

 

Paul

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