I’ve always found the manipulation of objects fascinating: cards, juggling, etc. One of my more recent dexterous interests came from watching bored students in college calculus spin their pens with easy agility. Have you ever wondered why they spin pens though rather than pencils? Fear of lead poisoning of course.
Lead poisoning from pencil lead is nearly impossible, making my previous pen-spinning comment ludicrous. Nearly impossible? Not totally? Ancient Egyptians used chunks of lead (Pb) to write with (wonder what they used for scratch ‘n’ sniff stickers). So, if you are writing with a pencil the ancient Egyptians used then it is plausible. If you use what modern Egyptians, and most of the world, uses then I am sure you will not get lead poisoning as modern pencils use graphite, a form of carbon.
While lil’ Johnny from second grade was right to tell you not to puncture yourself with a pencil, he was right for the wrong reason. If you sustain a shallow puncture you may have introduced germs under your skin – which skin tries to prevent. You may also require some hydrogen peroxide, an adhesive bandage, and bacitracin. If you give yourself a deeper puncture (remember do not run with sharp objects) then you probably introduced germs deep under your skin. You may also require some hydrogen peroxide, an adhesive bandage, and bacitracin or stitches, antibiotics, and a tetanus booster. If you run the pencil all the way through your hand you probably introduced bacteria, injured muscles, nerves, and tendons, a tetanus booster, require stitches, maybe surgery, and possibly hand rehabilitation. In any case, none of these situations are good because an infection may develop as some bacteria thrive on being under the skin where there is less oxygen (anaerobic environment) such as C. tetani. While you may require first aid for the puncture wound, you will not require chelation therapy for lead poisoning. So why spin pens instead of pencils? Because pens are number 1, and pencils are number 2.