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Get the Lead Out!
Lead poisoning has caused death and horrible suffering in birds and other wildlife, and also in human beings, for millennia. Many historians believe that lead even contributed to the fall of the Roman Empire, as people's minds degraded because of the leaded goblets and leaded pottery dishes used back then. The first known North American duck die-off from lead was at Stephenson Lake, Texas, in 1874. So people are concerned about lead for its effects on humans AND on wildlife.
Many poisons
in the environment slowly or quickly break down into less harmful chemicals.
For example, DDT, a pesticide used in the US from the 1940s until 1970,
is a complicated, big molecule that very slowly breaks down into smaller
molecules (including the equally toxic DDE). Eventually both chemicals
reacts with other chemicals and fall apart until they no longer hurt birds.
Chemists often design newer pesticides that break down faster than DDT
and DDE, so they won't be poisonous for more than a few days.
But lead is different. It's an element, so it's already as broken down
as it can get, and never gets less toxic in nature. And once lead is in
nature, there is no easy way to get it out. It's bad enough that so many
lead pellets and sinkers are already in lakes, ponds, streams, forests,
and fields, but people continue to add more. Most states still allow lead
to be used while hunting on non-Federal land (the US Fish and Wildlife
Service bans its use in waterfowl hunting everywhere, and on upland hunting
on all federal lands). And New Hampshire is the only state that currently
bans lead sinkers.
This lesson
has four parts.
1. How does
lead get into bodies?
2. What happens
to an animal with lead poisoning?
3. How do we treat
humans and animals that have lead poisoning?
4. What can we
do to help prevent lead poisoning?
1. How does lead get into bodies?
Lead gets into bodies three main ways.
- Getting shot: Pellets for shot guns and bullets for rifles used to virtually always be made of lead. When something is shot but not killed, the pellets or slugs that remain in their bodies can lead to low-grade, chronic lead poisoning, especially if a piece of lead is near or in a bone.
- Breathing it: Some industries such as smelting and battery manufacturing release lead into the air through smokestacks. When gasoline for cars used to contain lead, and the gasoline was burned to power the engine, the lead escaped in smoke through the exhaust pipe, and went into the air, too. The air we breathe isn't usually contaminated enough to cause direct problems.
- Swallowing
it:
There are several ways lead can be swallowed:- Rain washes lead in the air down to earth, where it collects in soil and water. Industrial areas and areas near highways and busy streets can get big build-ups of lead this way. And this causes household dust and the dust on playgrounds in these areas to have high levels of lead. Swallowing these particles can cause low-grade, chronic lead poisoning. That's a big reason why cars made since 1973 have had to be able to run on lead-free gas, and why leaded gas for cars is now banned in Canada and the US.
- Lead used to be a common ingredient in house paints, and is still found in some paints. Paint often peels and chips in places like windowsills. Babies and toddlers swallowing leaded paint can get chronic lead poisoning. Broken-down paint chips also contribute to the lead in dust.
- Glazes used in pottery often contain lead. This is okay for pottery made as artwork, but not for dishes or birdbaths! Many kinds of food and beverages dissolve small amounts of the glaze, and the person or bird can eat or drink the lead, too! If this happens often enough, it can lead to chronic lead poisoning.
- Shotgun
pellets at the bottom of lakes, ponds, and streams. Most of
the shot
used in duck and goose hunting doesn't actually hit anything, and rains down to earth. Every year duck hunters left about 6,000 TONS of lead shot in United States ponds, lakes and rivers before the US Fish and Wildlife Service banned its use in waterfowl hunting. And lead shot is still legal for use in "upland game hunting" (for grouse, pheasants, squirrels, etc.).This Golden Eagle #004 is a survivor of lead poisoning. She is being tracked by satellite. Learn more about her at Golden Eagle to Fly Free! 
This lead on the bottom of ponds, lakes and rivers is picked up by fish, and also by dabbling ducks, geese, and swans, who pick up a wide variety of tiny plants and animals on the bottom, sift out the water and mud through their strainer-type bills, and swallow the particles of food, tiny stones, and lead. The stones and lead remain in their gizzards (a chamber of their stomachs), helping them to grind their food. The stones in the gizzard slowly wear away into often-useful minerals. Lead is so heavy it sits on the bottom of the stomach for a long time, slowly but steadily dissolving and entering directly into the blood stream, causing acute lead poisoning. - In forests and fields lead shot can be picked up by grouse, sparrows, cranes, and other ground feeders. Of course ducks, geese, and swans pick up many more pellets than do upland birds and other animals, but it's still a problem in heavily hunted areas. Lead in the stomachs of these animals also causes acute lead poisoning.
- Lead sinkers lost by anglers sit on the bottom of the water, too, and are also picked up by fish, waterfowl, and loons. Sinkers are larger than pellets, so a single sinker can cause far more dangerous lead levels, and acute poisoning, than a single pellet. Lead shot is now banned for waterfowl hunting, but lead sinkers are still legal almost everywhere, except the state of New Hampshire, which banned its use in 2000.
- Predators and scavengers that eat prey containing lead shot often eat some of the lead pellets, which cause acute lead poisoning. Eagles and hawks often kill or scavenge on ducks killed or crippled by lead shot, and loons pick up fish that have swallowed lead shot.
- Scavengers eating deer that were shot but got away before dying also pick up the lead slugs in the bodies, causing acute lead poisoning.
2. What happens to a bird with lead poisoning?
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"Chronic lead poisoning is a long-term sickness from a lead bb being inside the bird, usually touching or inside a bone. Since blood is filtered in the bone cavity, it is in constant contact with the blood, and that means bad news for birds. Chronic is a low level, and causes kind of an "unthriftiness," making the birds more susceptible to a host of things including disease. They are slower so predation is a factor. They don't feel good so don't eat as well, and reproduction is either non-existent or they don't tend their families with the fervor needed to pull off good broods."
Marge tells us that birds with chronic lead poisoning usually die a slow and agonizing death. "The lead paralyses the intestine and eventually the legs. And it affects their central nervous system, affecting vision and making them mentally foggy, so they totally do not know what is going on around them. They die usually of starvation or predation." She adds, "They are scared. I feel it is like being drugged out on something and being able to see, but not comprehend well. It is a painful process for me and the birds. Emotionally I HATE it. It is slow and icky."
Acute lead poisoning is faster and more severe. Marge writes, "If they have a piece of lead in the gut where it is absorbed, they can't eat, and can't move, as paralysis is a typical finding. The heart is affected, showing arrhythmia. And the liver is poisoned trying to filter the toxin. The hematopoetic system goes bonkers with cells being kicked out prematurely. Anemia results and the bird dies of a multitude of issues that affect the entire body. Lead is NASTY."
3. How do we treat humans and animals that have lead poisoning?
Treating lead poisoning is a long process, sometimes taking months. In the case of humans, the problem is usually discovered in time, but most wild birds aren't found and captured until the poisoning is very advanced, and despite the most professional and compassionate care, victims often die.
Lead is a stable element that doesn't break down into anything else, and quickly binds to tissues that it harms, so isn't filtered out of the body through the kidneys. The only way to "get the lead" out of a body is to use a chelate, that is, a chemical that binds to the lead, taking it out of tissues and putting it into the blood so the kidneys can excrete it. One chelate often used to treat lead-poisoning victims is called Calcium Disodium Versenate (Calcium EDTA). Marge Gibson says it is very expensive. "I had a Bald Eagle last year that had a serious case of lead poisoning. The pharmacy cost to us was over a thousand dollars for that bird. He was released and I hope is having a wonderful life."
4. What can we do to help prevent lead poisoning?
Marge Gibson says "People need to take responsibility for the lead issue. I think every person that hunts with lead shot or fishes with lead sinkers should sit with me during a lead poisoning case and hold the bird and see the pain and the horror they go though for days, weeks, months. That would change their minds. It would have to."
What can WE do to help? If you hunt or fish, make sure you buy shot or sinkers made of steel. To get samples and information, write or email Bullet Weights® today! IMPORTANT: You must mention Journey North to receive samples and information.
Write:
Bullet Weights®
P.O. Box 187
Alda, Nebraska 68810
OR
E-mail your order form to Bullet Weights. (In the blank for "Company" or "Message," please write "Journey North Student Offer.")
Also, find out if your state or province allows lead shot for hunting, and lead sinkers for fishing. If so, write your concerns about this to people in public office who might be willing to change the laws.
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