In order to answer this question, you need to know some facts. First of all, prior to 1983, lead soldering was used in the installation of copper tubing. This use of lead was part of the soldering that held copper pipes together. So even though you may have copper pipes, you may have lead in your water because of the soldering that no one thought would show up in the water supply.
Since then, the use of lead-free solders has eliminated the use of lead to hold together copper piping in residential homes. However, if you have a home that was built prior to 1983 and was installed with copper tubing, lead was probably used to solder the pipes together. This isn't necessarily a panic situation, but one that you need to be aware of in order to maintain your health and safety.
This is why if you are buying a home, it is a good idea to consult a local plumber who knows the area. They can inspect your pipes, give you an estimate of when they were installed, and what materials were used to put them together.
In the meantime, here is a great plumbing tip: Water has the highest lead content when it is dormant in the pipes. The word 'dormant' usually refers to water that sits in your pipes for about six to ten hours. If you haven't used the water during the day, to help protect yourself from lead, be sure to run the water a few minutes before drinking it. Also, if you can't replace the soldering on the copper pipes, consider a water filter that gets rid of lead. Again, your local plumber can recommend the right water filter and have it installed at a low cost; this until you can replace the lead soldering on your pipes.