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Testing for Zinc in
Parrot Toys,
Play Gyms, and Cages
By Ed Harris
Originally Published in Companion Parrot Quarterly, Issue #53,
Summer 2001
Revised May 27, 2003
Last fall, I became
concerned that our new baby Timneh African Grey parrot Scooter might
have come down with zinc poising. His symptoms were consistent with
this diagnosis – lethargy, loss of appetite, excessive urination,
and diarrhea. And his favorite thing to chew on is the metal parts
of toys or the quick link connectors that fasten the toys to his
cage or play gym. It turned out that he was fine, but I started to
wonder how prevalent zinc was in parrot toys and play gyms. Before I
talk about how to test for zinc in parrot toys and play gyms, it is
worth briefly talking about the problem of zinc toxicity (also
called zinc toxicosis) in pet birds. (It should also be noted that
dogs are also quite susceptible to zinc poisoning, usually from
swallowing metal parts that are coated with zinc.)
The Diagnosis of Zinc Toxicity in Pet Birds
Zinc is a heavy metal that is used to coat iron or steel in a
process called galvanization to prevent rust. Galvanized wire and
toy parts are common sources of zinc. Unfortunately, parrots are
often drawn to shiny objects. They also have a lot of spare time to
play with, suck on, chew, and destroy anything within reach.
Signs and symptoms of zinc toxicity can be very similar to other
illnesses. The bird just feels bad and may regurgitate, have
diarrhea, excess urination, reduced appetite, and lose weight. The
birds can become anemic and develop a bluish coloration due to lack
of oxygen. In severe cases, the bird can become week and develop
seizures. Feather picking can also result. Feather color changes can
also occur.
Diagnosis of zinc toxicity is done by a combination of x-rays and
blood tests for zinc levels. In some cases the x-rays may show metal
present in the bird’s digestive tract. Most laboratory values are
normal with zinc toxicity, which may lead to an incorrect diagnosis
of a “mild infection”. Treatment is often with injections, followed
later by an oral drug to bind and remove the zinc. This is known as
chelation therapy. A laxative may also be used to help remove the
metal by flushing the digestive tract. If caught early, treatment is
usually successful.
The issue of zinc toxicity is very controversial within the avian
community. Some vets feel that the problem is under-diagnosed and
there are a significant number of cases of zinc toxicity that are
diagnosed as other problems, especially by non-avian vets. On the
other hand, other vets feel that there is little evidence that the
problem occurs with any significant frequency. This article does not
take a stand on this important issue and I feel that this is an
appropriate topic for discussion with your avian vet. The focus of
this article is to provide information on how to test for zinc in
parrot toys if you are concerned with this issue and what to do if
you do find zinc coated metal parts on your parrot’s toys, play
gyms, or cages.
Testing for Zinc in Parrot Toys and Play Gyms
The first question you need to ask yourself is whether or not you
even want to deal with the potential problem of zinc coated metal
parts. If your bird does not chew on the metal parts of toys, then
you don’t have a problem even if the toy parts are zinc coated. I am
not a fanatic on this issue – my budgie, Billy, does not chew on
metal toy parts and I have chosen to leave his play toys and play
gyms unchanged, even though I know that many of his toys contain
zinc plated parts.
There are many great parrot toys on the market that are either
constructed of wood, plastic, and leather parts only or are made
entirely with stainless steel. There is a partial list of companies
that sell only parrot safe toys at the end of this article, as well
as some companies that sell stainless steel components you can use
to reduce or eliminate the potential problem. For example, if you
have a play gym that has screw eyes to fasten toys, it is very
likely that the screw eyes themselves are zinc coated. Rather than
go through the potentially dangerous process of testing the screw
eyes for zinc, it probably makes much more sense to simply replace
the screw eyes with stainless steel screw eyes from one of the
companies listed at the end of this article. Another easy to deal
with problem is quick links. If you are unsure whether or not the
quick links used to fasten the toys to the cage or play gym are
safe, you can replace the quick links with stainless steel quick
links. This can get fairly pricey however if you have a lot of quick
links to replace. Another very easy and very cheap alternative to
quick links is to buy inexpensive cable ties from a hardware store.
These typically come in bags of 10 to 100 ties and are very
inexpensive. The disadvantage is that the ties are not reusable: if
you need to move a toy, you will need to cut the tie and replace it
with a new one.
One cautionary note on cable ties: many of the larger parrots can
easily chew through nylon cable ties and potentially swallow the
resulting small pieces. If your bird is a chewer, you should avoid
the use of cable ties and stay with stainless steel quick links. In
any case, if you do choose to use nylon cable ties, be sure to make
sure that the resulting loop is small enough so that it doesn’t
become a hazard to your bird.
A Note about Parrot Cages
Parrot cages are available in a wide variety of finishes. The most
common finishes are chrome, brass, painted metal, powder coated
metal, and stainless steel. Stainless steel cages are completely
safe, but are substantially more expensive than other options. Many
powder coated cages come from major manufacturers and are fairly
expensive. It is my understanding that the powder coating used in
these cages is zinc free and even if your bird chews the powder
coating off the metal, the steel underneath is not zinc plated. That
makes powder coated cages a good choice.
When you get a small parrot cage from a pet store, you are much more
likely to find cages that are either painted metal, or brass, or
chrome plated. Unfortunately, the methods described below cannot be
used to test for zinc in either painted or powder coat cages. I am
looking into ways to test paint for zinc, but have not yet
determined a simple way to do this. It is worth noting, however,
that even if there is a small amount of zinc in the paint; this is
not as bad as zinc plated metals which are essentially pure zinc.
Brass is an alloy of copper and zinc. Cages that are brass plated
will tarnish over time and since the plating is not too strong, it
can easily be chewed off by an aggressive parrot. While the zinc
content is lower in a brass plated cage than a zinc plated cage,
brass plated cages should be avoided.
Chrome plated cages can either be nickel or zinc plated. As
described later in this article, it can be difficult to tell by
looking at the plating. If you have a chrome plated cage, I
recommend testing it for zinc using the methods described below. I
would be especially concerned if the cage is “home made” by a small
shop since they are much less likely to be aware of the zinc problem
than a large, reputable manufacturer.
Is It Stainless Steel?
Depending on whom you purchased your toys or play gyms from, you may
already have safe toys. Testing for stainless steel is very easy.
Take a magnet and see if the quick link, screw eye, chain, metal
wire, etc. is attracted to the magnet. Stainless steel is not
magnetic, so if the metal part does not stick to magnet, the odds
are very good that the part is stainless steel and is completely
safe for your bird. Note, however, that some lower grades of
stainless steel are slightly magnetic. They will be attracted to a
magnet but not at all like a regular steel part. So far the only
parts I have seen which have this property are some metal o-rings I
purchased to fix some toys.
One cautionary note however: while I haven’t yet seen any toys made
with aluminum parts, it is possible that some toys are made with
aluminum wire or rings. Aluminum is also not magnetic. I am not
aware of any safety problems with aluminum and birds, but since I am
not qualified to address this issue, I would suggest either
discussing this issue with your avian vet or avoiding aluminum if
possible. Stainless steel and aluminum look very different.
Typically stainless steel has a fairly bright finish (although not
as shiny as some chrome plated metals), while aluminum is usually a
dull color. Also, aluminum is very soft. You can easily scratch
aluminum with a knife while stainless steel will be very scratch
resistant.
Can I Just Ask the Toy or Play Gym Company?
It is my belief that no toy or play gym company wants to put out
toys that are dangerous to pet birds. Some of the companies go to
great pains to make sure that their toys or play gyms are as safe as
possible for birds. Unfortunately, for the most part, parrot toy and
play gym making is mostly a cottage industry. Many of the people who
make parrot toys are simply not aware of the problem with zinc
toxicity. And even if they are aware of the problem, they may not
want to use stainless steel parts because they can be difficult to
find and they can add significantly to the cost of the toys.
Stainless steel is also harder to cut and work with than less
expensive metals.
If you are ordering toys from a mail order or Internet company or
from a local pet store you should certainly ask if the toys contain
any zinc-coated parts. My experience has been that most dealers
assume their toys are safe but unless the toys are specifically
noted as being made only with stainless steel parts, they have no
way of knowing for sure what the toys are actually made of. If you
buy toys from a bird fair, you sometimes are buying directly from a
local company who makes the toys and you can ask them about how
their toys are made. However, in many cases the folks who make the
toys simply do not know. If you are buying toys or play gyms
directly from the manufacturer, you should directly ask the question
about how the toys are constructed. However, as I recently learned
even the best-intentioned toy or play gym manufacturer may be
unaware that their toys are not completely safe. I recently
purchased a beautifully designed wooden play gym from a very
reputable manufacturer. Before ordering I specifically asked about
the metal parts. I was told that the metal parts were all stainless
steel. However, when I received the gym I did the magnet test and
quickly discovered that none of the parts were stainless steel. When
I called the company to ask about this I learned that the company
thought that had been purchasing stainless steel parts for their
play gyms. When I explained that the parts were not stainless steel,
the play gym company immediately contacted the vendor who supplies
their metal parts, including screw eyes, chain, and quick links. The
play gym company called me back to indicate that although the parts
were not in fact stainless steel, they were nickel plated steel and
were completely safe. I then checked all of the metal parts using
the method I will describe later in this article. It turned out that
the chain and quick links that they were using were in fact
nickel-plated steel and were safe. However, the screw eyes used for
holding toys were zinc-plated and thus not safe for birds. I then
called the company back with my findings. I was very pleased with
their response. They apologized for the problem and indicated that
they would immediately send me out replacement stainless steel screw
eyes for the two play gyms I had purchased from them (which they
did). Also, they decided to stop shipping play gyms until they could
replace the screw eyes with stainless steel ones. This is the kind
of company I like dealing with.
So what can you conclude from this? If a major toy manufacturer
indicates that all of their metal parts are safe, there is a
reasonably good chance that they are, but you are not guaranteed
that this is the case unless all parts are stainless steel
(non-magnetic). At the end of this article I will give some
guidelines for visually inspecting metal parts that can help you
identify at least some unsafe parts.
Testing for Zinc Coating
According to the American Zinc Association, zinc is almost never a
component of steel, but rather a coating to prevent rust. Even if
steel is partially made from recycled metals that are zinc coating,
the re-melting process burns off the zinc. As an impurity, zinc
causes steel to become brittle so it is not a component of the steel
itself.
The good news is that since zinc is a coating it is relatively easy
to test for zinc chemically. The bad news is that the chemical used
to test for zinc is hydrochloric acid, which is dangerous stuff to
work with. While hydrochloric acid is generally not available to the
general public, there is a somewhat diluted form of hydrochloric
acid called muriatic acid which is easy to obtain and a little less
dangerous to work with.
WARNING: Any handling of muriatic acid for testing for zinc should
be done outside in a well-ventilated area. You should be wearing
rubber gloves and lab type eye goggles with sides. You should also
wear long pants and a long sleeve shirt to minimize the chance of
getting any acid on your skin. Also, you should have water readily
available so you can quickly wash off any acid that accidentally
splashes on your skin or clothing.
If in spite of these warnings you want to test for zinc, here are
recommended steps to follow:
1. Muriatic acid can be purchased at most paint stores or hardware
stores that have a paint department. Typically the smallest quantity
you can purchase will be in a quart bottle. It is not very
expensive.
2. You can test for zinc using a single drop of acid, so it is safer
to transfer a small amount of the muriatic acid to a small
container. I recommend that you obtain a new empty glass medicine
bottle with a dropper built in. I was easily able to purchase one
for 50 cents at my local pharmacy.
3. Working outside wearing protective gear, transfer a small amount
of muriatic acid to the medicine bottle, being careful to not
breathe in the fumes. Since the top opening of the medicine bottle
is small, you should use a small plastic funnel to pour the acid
into the medicine bottle. Do not use a metal funnel unless it is
stainless steel – the acid will probably dissolve it. Alternatively,
you can pour a small amount of the acid into a glass measuring cup
with a pouring spout and then carefully pour it into the medicine
bottle. After the transfer is complete, you should close the bottle
and wash the outside thoroughly with water (as well as the funnel or
measuring cup) to remove any remaining acid. This is actually the
most dangerous part of the testing. Once the acid is transferred to
the medicine bottle you will only be using a drop or two at a time.
4. To actually test things for zinc, you will need two things: 1) a
bucket filled with cold water which you will use to dunk toys and
other metal parts to quickly wash off the test acid, and 2) a glass
plate or baking dish which is where you will place the item you are
testing. (See below for suggestions on how to test cages.)
5. When muriatic acid is put onto a metal part with zinc coating,
you will see an immediate and vigorous foaming reaction. The area
where the acid touches the zinc will sometimes turn almost black,
although this does not always happen. In order to get an idea of
what type of reaction you are looking for, I suggest you obtain a
galvanized roofing nail from your hardware store, building supply
store, or your friendly neighborhood handyperson. Working outside
and wearing protective gear put the nail on the glass plate and put
a single drop of acid on the nail. You will get a vigorous chemical
reaction. Then try the same thing with something you know is
stainless steel, such as a piece of tableware. You will get
absolutely no reaction when the item is stainless steel. This will
also be the case if the item is nickel plated rather than zinc
plated.
6. Use the same procedure to test toys. Note that a toy may have
several metal components, for example, chain, quick links, a metal
loop fastening chain to a plastic object, a metal wire used to
string together wood or plastic parts, etc. As soon as you have
tested the metal parts of the toy, immediately dunk the toy in the
bucket of water to dilute the acid. You should thoroughly rinse the
toy later before using it with your bird.
7. Play gyms usually have metal screw eyes or other metal parts for
hanging toys. Remove one of each type of metal part from the play
gym and test it for zinc. This includes any nuts or bolts that hold
things together. One of my plastic play gyms has metal toy hangers
made out of stainless steel, which is great. However, the toy hanger
is fastened to the play gym using a regular nut and a wing nut, both
of which turned out to be zinc coated!
8. Testing chrome plated cages can be a bit tricky. Since it is not
safe to test for zinc indoors, you need to move the cage outside to
test it. I have noticed that most cages that are chrome plated are
small portable cages, so moving it outside is not a problem. If you
have a large parrot cage, you will need to move it outside, which
may be a bit of a challenge, especially if the cage won’t fit
through the door! In any case, once the cage is outside, remove any
perches or toys that might be damaged by water. Have a garden hose
handy to rinse the cage after testing. All you need to do is put one
drop of acid on the cage bars and see if you get the zinc reaction
described above. As soon as you do the test, thoroughly hose down
the cage to make sure that all of the acid has been rinsed away.
One alternative to testing for zinc yourself that you may want to
consider is to see if there is a local commercial analytical lab in
your area that can do the testing for you. Another alternative is to
check with the toxicology lab at a nearby University. They may
charge a small fee for the testing, but at least you won’t need to
handle dangerous chemicals yourself.
What if You Find Zinc-coated Parts?
If you test a number of toys and play gym parts, it is very likely
that some of these parts will be zinc plated. Your bird may not chew
on the particular metal parts, for example, a quick link or a small
exposed wire, in which case there is probably no reason to replace
the toy or part. However, if you have a metal chewer like I do, you
will need to take some action to protect your bird. Here are some
suggestions:
1. If your bird shows any of the signs and symptoms listed earlier
in this article, then you should consult your avian vet for advice
about possible testing for zinc toxicity.
2. Contact the toy manufacturer or company you purchased the toy
from to see if you can return it or exchange it for a safe toy. If
you have a play gym with metal parts, ask them to send you stainless
steel parts to replace the unsafe parts.
3. In many cases it is possible to modify or rebuild the toy to make
it safe. At the end of this article are some places where you can
purchase stainless steel parts, including quick links, screw eyes,
metal loops, chain, and wire. Components like screw eyes and quick
links are generally easy to replace. In some cases you may be able
to figure out a way to “hide” the non-safe part. For example, one of
my bird’s favorite toys is a coiled rope-covered hanging toy (“Boing”)
that contains an unsafe metal wire core. All of the wire is
completely covered, however, except for a small section at the top
that is connected to a quick link to hang it. Naturally, this was
the part of the toy that Scooter prefers to chew on. I made a small
extension loop out of stainless steel wire and used a hollow wooden
toy part to cover the exposed metal. The stainless steel wire loop
fastens to the unsafe metal wire, goes through the wooden toy part,
and has a loop at the top that is used to hang the toy using a
stainless steel quick link. I have also replaced the wire in several
toys with stainless steel wire, metal loops with stainless steel
loops, etc. Be creative – you can often figure out a way to modify
or rebuild many toys or at least use the safe wooden or plastic
parts to make new toys.
4. Stainless steel is much harder than normal zinc-coated steel. You
will need heavy-duty wire cutters to cut through stainless steel
wire and long nose pliers to bend it. Also note that even though the
wire used to string together a toy may be larger in diameter, you
should probably not use stainless steel wire thicker than 1/16”
because it will be very hard to cut and bend. Stainless steel chain
can be cut with a hacksaw or with a heavy-duty bolt cutter. Make
sure you wear safety goggles when you cut or bend stainless steel
parts.
Visually Inspecting Toy Parts
Having tested a great number of metal toy parts and play gym
components, I can give you some guidelines as to what to look for if
you do not want to go through the testing process.
• Any metal parts that are not shiny are probably zinc-plated steel.
For example, many perches have large washers at one end that are
used to fasten the perch to the bars of the cage. Generally these
washers are zinc-plated. On some of the perches you can easily
replace the washers with stainless steel washers to make the perch
safe. However, the cholla wood perches mostly seem to have one of
the washers glued to the wood, which makes replacing the washer
difficult to do.
• If the toy contains a wire core used to string wooden or plastic
parts, the wire itself is probably zinc-plated. Wire is also
sometimes used to fasten parts of the toy together. If the wire is
magnetic, it is almost certainly zinc-plated.
• Screw eyes on play gyms are likely to be zinc-plated. You can
easily use a magnet to see if they are stainless steel.
• Metal chain is a mixed bag. Some chain is nickel-plated and is
safe. Other chain is zinc-plated and is not safe. You generally
cannot tell the difference unless you test it.
• Quick links are also a mixed bag. Some are nickel-plated and safe;
others are zinc-plated and unsafe. You need to check for zinc or
replace them with stainless steel quick links.
• The brass used to make brass-plated steel is made up of copper and
zinc. Depending on the proportions of copper and zinc the platings
can potentially be toxic. I have tested some samples of brass-plated
steel and gotten no zinc reaction indicating that they are probably
safe, but it is probably not a good idea to assume that all
brass-plated steel is safe. With pure brass, the zinc and copper are
tightly bound so it would be necessary to ingest a piece of a brass
object to get a significant amount of zinc into the system. I would
recommend avoiding brass if possible.
Summary
In this article I have tried to address the issue of zinc toxicity
in pet birds and how you can make sure that your toys are free from
zinc. If you have any questions, I can be reached at eharris@synnovation.com. |
