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A buddy of mine has a bunch of old electronics that were his fathers that were in storage for a long time, and some of them look pretty bad.

Some of the items look similar to what is shown in this picture:

enter image description here

With blue spots, nasty oil looking brown spots, and similar brown damage/build up on chips and parts.

I am curious how dangerous stuff like this could be for human handling, as well as being in his attic breathing while around this stuff? Are there any worries one should have?

NOTE: I'm not sure if this is a question better suited to biology/chemistry due to the nature of interaction with humans/chemicals, but figured since this is about electrical components it would best be suited here.

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    \$\begingroup\$ Copper metal reacts with oxygen, resulting in the formation of copper oxide, which appears green in color. Its harmless as long as you don't consume it. As an interesting fact, copper corrosion is non-destructive, the green copper oxide layer even acts as a protective layer. \$\endgroup\$
    – Rev
    Commented Jan 17, 2017 at 11:13
  • \$\begingroup\$ Try not to lick or eat it. \$\endgroup\$
    – PlasmaHH
    Commented Jan 17, 2017 at 11:14
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    \$\begingroup\$ Some of that stuff may be organic in origin- from pests or vermin excretions. Sometimes that kind of stuff carries pathogens. Had a airborne computer that was stored in a hangar with mice and it ended up with small green color mouse turds throughout. Ugh. \$\endgroup\$ Commented Jan 17, 2017 at 11:22
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    \$\begingroup\$ I've seen material looking much like that after a battery has leaked inside the product, the "B1" on the silkscreen on the photo seems a likely candidate. There could be residual corrosive compounds left over which would potentially be harmful by direct skin contact. It won't do your clothing any favours either. \$\endgroup\$
    – user98663
    Commented Jan 17, 2017 at 11:23
  • \$\begingroup\$ Thanks all for your comments. I'm curious how far some of this would spread when touching? I believe Jeff had shipped out some packages after finding stuff in the attic to sell, so 'I'm not sure if those boxes/packages were contaminated with anything after possibly touching the nasty stuff? what he shipped wasn't any of this damaged stuff, but I don't know if he had touched anything else before shipping it out. I'm not sure if that is something that the buyer should be notified of, but I think it sounds like they should be. \$\endgroup\$
    – XaolingBao
    Commented Jan 17, 2017 at 20:46

2 Answers 2

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The green/blue substances are, as already noted by Andrew and Rev1.0, copper and or nickel compounds.

But to have them grow to such size there have to happen heavy corrosion processes which usually take place in presence of water and electrolytes.

The brown sediments usually are corrosion byproducts from different metals like iron.

Also already mentioned is the fact that old PCBs contain roughly 30% lead in the solder points which is automagically released into similar crystalline products. So the green and brown stuff will be contamined by lead compounds.

Anorganic heavy metal salts like those colourful crystals don't tend to evaporate. So you probably are safe if you only look at them. Incorporation could take place, if you touch those salts and either keep remnants on your skin for a prolonged period or by ingestion when you touch your face or food with dirty fingers. So take care to wear simple safety gloves when handling.

If you want to dispose of those parts ask for companies specialised in handling electronic waste.

If you want to salvage those things you may want to clean them to reduce the risk of possession and handling. Cleaning could take place with deionized water and an ultrasonic cleaner several times and washing with Propan-2-ol (aka isopropylic alcohol) afterwards. This probably has to repeated several times. The washing byproducts have to be disposed of by companies for handling chemical waste, as they pose an environmental risk. Heavy metal salts are of high aquatic toxicity, so you should not put it down the drain.

After cleaning the circuits have to be stored dry and perhaps can be protected with a conformal coating from future corrosion.

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  • \$\begingroup\$ Thanks, So it seems that lead is one of the bigger things to worry about, but what about corrosion of metals? I found this picture i.ebayimg.com/images/g/IHcAAOSwUKxYd5CD/s-l1600.jpg which seems to be pretty gunked up with nasty. Would you say this is also corrosion of the parts? I found it interesting because it looks to be an unused piece, and not something inside a circuit. I would assume that when dealing with any old vintage electronics one should wear gloves to avoid lead contact? Lead-Free seems to be required in electronics now. \$\endgroup\$
    – XaolingBao
    Commented Jan 17, 2017 at 20:24
  • \$\begingroup\$ That thing on the picture seems to be an integrated circuit still in the complete lead frame from the manufacturing process. But you are right, it looks heavily corroded. Even the gold plating could not protect the lead frame. \$\endgroup\$
    – Ariser
    Commented Jan 17, 2017 at 21:24
  • \$\begingroup\$ @XaolingBao as long as there are no signs of corrosion, handling of electronics containing lead is pretty safe. Just don't lick it. If there are corrosion remnants you have to remove them if you want to operate it. Corrosion can take place anytime if storage conditions are bad (high humidity and chemical residues from different sources), even if the parts were never used. \$\endgroup\$
    – Ariser
    Commented Jan 17, 2017 at 21:31
  • \$\begingroup\$ Wait... Lead frame? It's gold plated lead or...? Seems like that's something we should be wary of when touching similar frames, since I've seen a bunch of them in similar "Frames." In this case there is signs of corrosion, so how should we proceed? I don't think any of these are going to be used for operational use, but more along the lines of collections and possibly even gold scrapers. It's probably due to humidity from the attic. \$\endgroup\$
    – XaolingBao
    Commented Jan 18, 2017 at 0:47
  • \$\begingroup\$ lead frame is only a "name" for the metallic structure, they are manufactured from different alloys and contain, if any, only few lead. Of course, copper, nickel or other salts can also be unhealthy if incorporated. So for collecting, one should clean it and treat it with conformal coating. \$\endgroup\$
    – Ariser
    Commented Jan 18, 2017 at 10:23
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The solder will have lead in it so it's reasonable to assume that any dust breaking off from the board will contain small amounts of lead.

Blue would normally imply some sort of copper compound.

I'm no expert but I wouldn't think it's a risk unless it's getting disturbed and and the dust breathed in regularly. I'd wear gloves when handling it and possibly a basic face mask depending on how bad it is, I think that's being paranoid but best to be safe.

Since it does have lead you should check if there are any local recycling/electronics disposal sites that you can take it to rather than putting it in landfill where the lead will find it's way into the groundwater. What's available varies a lot depending on where you are.

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  • \$\begingroup\$ So you think it's okay for us to handle chips like this as long as we use gloves and such? Is there any airborne risk from inhalation around these parts? He isn't looking to get rid of the parts, unless there is some sort of danger. \$\endgroup\$
    – XaolingBao
    Commented Jan 20, 2017 at 14:53
  • \$\begingroup\$ I wouldn't start sniffing the boards but if they are just sitting there with nothing kicking up dust there shouldn't be an airborne risk. But why keep them? Does he expect them to work in that state? If they aren't going to work then why keep them? \$\endgroup\$
    – Andrew
    Commented Jan 23, 2017 at 11:46
  • \$\begingroup\$ He is looking to keep a collection of computer chips and parts. The damage is not as bad as shown in the picture, that was just a good example. I personally would not keep something that looked anything like the above picture. \$\endgroup\$
    – XaolingBao
    Commented Jan 24, 2017 at 9:41

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