[This story appears as an on-going series in the "Gilroy Dispatch"]
Lead: A toxic threat to wildlife and humans May, 2013 By Amy Yee
Lead is a naturally occurring metal and has been around since the earth was created. Why all the fuss about its toxicity?
Many naturally occurring elements are toxic, either alone or when combined with other elements. The element oxygen is essential for life, but carbon and oxygen can combine to make carbon monoxide, a deadly gas. Hydrogen and oxygen combine to make water, yet hydrogen by itself is extremely explosive (remember the Hindenburg?) Humans have learned to manage earth's elements for their benefit, and to cause the least possible harm to themselves and the environment.
Governments around the world have regulated and mandated safety measures for the use of dangerous elements, such as lead, for many generations. Above a certain level, lead is dangerous to people, animals, and plants. Lead paint was banned in the 1970s because the ingestion of even small chips was proven to impair brain function. We no longer sell leaded gasoline, or use lead in water pipes, ceramic eating utensils, toys, or jewelry. We have banned lead solder in cans used to sell food products.
Why is lead so dangerous? Lead inhibits the ability of humans and animals to synthesize red blood cells. Red blood cells contain a protein called hemoglobin, which contains iron, which transports oxygen and carbon dioxide. Without well-functioning red blood cells, living creatures die.
Lead poisoning also affects the stomach, kidneys and nervous system. In children, it can also cause behavior problems, learning difficulties and slow growth rate. The effect is cumulative and cannot be reversed when the source of the lead is removed.
The California State Assembly is currently considering a bill to ban lead ammunition for all hunting in the State of California. The ban would be phased in over the next couple of years. The use of lead ammunition has been prohibited in parts of the state since 2007. This bill would expand the ban to the entire state.
Here's the problem: lead ammunition breaks up into lots and lots of very tiny pieces when it enters the body of the target animal. When people or animals eat that meat, they eat the lead, too.
The California Condor, a relative of the Turkey Vulture, is a scavenger (animal which eats carrion, or dead flesh) with a 7' wingspan. Its fragile existence (only about 400 California Condors remain in the wild) is threatened even further when it eats game, or parts of game, killed with lead bullets. Condors are just as susceptible as humans to the effects of lead in their diets. They, along with eagles, hawks and other animals that also eat carrion, have suffered slow and painful deaths from lead poisoning.
But condors, eagles and hawks are not the only creatures affected by lead ammunition. Humans who consume venison, wild pig, waterfowl or game birds killed with lead bullets are equally at risk.
Other types of ammunition (for example, solid copper) do not break into small pieces when they hit the target. The ammunition remains intact, effectively killing the target but not tainting the meat with dangerous fragments of toxic metal.
LOWER LEFT: X-ray of a package of venison, lead fragments are circled in red. (From: www.nps.gov)
LOWER RIGHT: A fragmented lead bullet compared to intact copper bullet. (From: www.nps.gov)
Lead poisoning can be treated with a process called chelation therapy, a treatment involving large doses of Vitamin K. Sometimes, if caught soon enough and the amount ingested is small, the animal or human will survive. However, the damage done by lead poisoning cannot be reversed, it can only be halted. If the brain, nervous system or kidneys are already damaged, they will not recover to their former state of function.
Wildlife and humans across the state will be safer when every possible step is taken to reduce our exposure to lead in the environment.
Amy Randall Yee has lived in Santa Clara County for 35 years and has volunteered at WERC for six years. She is the President of the Board of Directors of WERC. Contact her at firstname.lastname@example.org.
W.E.R.C., the Wildlife Education and Rehabilitation Center provides the community with rehabilitation services for orphaned, injured and sick native wildlife. Through our educational programs, W.E.R.C. encourages a peaceful coexistence between civilization and our native wildlife. Federal tax ID #77-0324296