I am a chemist as well, and specifically I work in the trace metals dept of an environmental lab. I analyze samples of water, soil and sediment for a variety of metals including lead.

The solubility of metallic lead is mainly a function of pH. Several other factors also influence its solubilty like heat and hardness of receiving water, but pH has the most impact. River water in our near by streams can be described as soft - low mineral content and slightly acidic. The pH of our river water is not low enough to dissolve lead at a very appreciable rate. Not to say that some doesn't dissolve, but not very much or at a very high rate. It's my opinon that lead that is left in our rivers by fishing probably is farily stationary. It has low surface to weight ratio which would further discourage the lead from dissolving.

So what is the fate of pencil lead in a stream bed? Lead will probably be quickly buried in the stream sediment after a few big storm events because of its density. It's exposure to stream water that would dissolve it will be very limited or nonexsistent. I wouldn't expect this buried lead to cause much risk to the environment.

If lead is exposed to highly acidic conditions - like what exsists in the stomachs of animals lead will be dissolved fairly easily. This is why lead is a concern in playgrounds where childern are playing beacuse of their tendency to ingest dirt. This is also why lead shot is a concern for waterfowl hunters. Lead shot is ingested by birds eating off the stream and lake beds passing through its gut track. The lead shot from the hunter who is eating the bird probably has little impact on the amount of lead that is being consumed in that bird. The lead that the hunter is consuming has been incorperated into the birds tissues by first passing through its gut tract.

As a chemist and outdoorsman I don't like to lead in our rivers. Science and justification aside it just doesn't seem like a very good idea, especially if alternatives are available. I would like to have as little impact on our precious resources as possible while still being able to enjoy them.

I think this is a good topic. It makes you stop and think for a minute. Is this the best thing for our rivers lakes and streams? Couls i or should I do something different? It is a good thing for all of us to keep asking these questions.

Steve