This is nothing to lose sleep over. While it is certainly true that lead is toxic and you shouldn’t eat it, the potential hazards of the involved toys have been way overblown.
So, some toy tennis balls like this have lead paint in the pawprints. How much of this would your dog have to actually eat in order to have a problem? Here is what Sharon Gwaltney-Brant DVM, PhD, DABVT, DABT of the ASPCA Animal Poison Control Center says:
"So let’s calculate a toxic dose for a 10 kg (22 pounds) dog. Assuming worst case scenario, we know that chronic toxicosis is induced at 3-30 mg/kg/day; we’ll use the 3. For a 10 kg dog, that’s 30 mg of lead per day times 90 days (3 month subchronic study) for a total lead dose of 2700 mg. Let’s also assume that somehow the dog manages to eat 1/2 oz (15 gm, 0.015 kg) of leaded paint (at 30 ppm) off of these toys every day (unlikely there’s even that much total paint on a toy, but we’ll call this worst case scenario). So every day the dog is eating 0.45 mg of lead; it’ll take 6000 days to get to the chronic toxic dose of 2700 mg of lead. That’s 16.4 years. So, if the dog, every day, scrapes off 1/2 oz (1 tablespoon) of paint from toys/bowls whose paint contains 30 ppm of lead, the dog might finally develop lead toxicosis when it hits 16 years of age. Very very unlikely. Allowable levels for humans should be fine for dogs, especially since dogs don’t live as long as we do (risk assessments for humans have to take into account our long life span). "
My brothers and I have laughed about the concerns with children’s toys and lead paint. Certainly it wouldn’t be funny for children to be poisoned by eating their toys, but we had toys made out of lead. In fact, we made them ourselves, in our room, without adult supervision, when our ages were 4, 7 and 11. First, you coat the cast-iron molds with soot by using the open flame of a candle. Then the two halves of the mold are clamped together. In the meantime, the lead has been heating up until it is all melted, its liquid surface shimmering like silver.
Now, while we inhale the acrid fumes, the cauldron of molten lead is tipped carefully to pour the mold full, making some shiny new lead soldiers. Of course, sometimes we weren’t as careful as we should have been. Once some hot lead landed on my toe. We were in our pajamas and barefoot while doing this. I skipped briskly to the bathroom and dunked my toe in what commercials used to refer to as "the bathroom bowl". This was screamingly funny to my little brothers, and little children often find it amusing even today.
So, you shouldn’t eat lead paint, and the Chinese are bums for putting it on toys, but your dog is probably not going to get enough to hurt him… unless he helps us make lead soldiers.