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According to both the American Veterinary Medical Association and the American Society for the Prevention of Cruelty to Animals, pets are more likely to exceed recommended levels of lead exposure through household contamination rather than by pet toys. Pets and children may be exposed to lead contained in consumer products like lead sinkers used to weigh down fishing lines, the consumption of old paint chips, linoleum, certain paints used by artists, or the inhalation of lead dust when surfaces of older homes are scraped or sanded. Old paint may contain up to 40% lead and is the most common cause of poisoning. In the last two years the Animal Poison Control Center has not taken even one call relating to lead poisoning by toys. The center has, however, managed hundreds of lead exposure cases due to environmental lead contamination.

Lead absorption is greater in young animals – especially when they are receiving low levels of dietary calcium. Cats may also ingest lead particles while grooming themselves, especially when a home has been recently renovated, due to contamination with lead dust.

Lead shot that becomes embedded in a pet’s tissue is poorly absorbed unless it is in or near the animal’s joints. Synovial fluid is relatively acidic and may increase lead absorption in joint areas.

Unfortunately, that does not mean that lead poisoning may not still occur through a toy manufactured in China for the American market. Toys from China have been found to contain up to 30,000 parts per million (ppm) in the paint on a pet toy. Currently there is no federal standard regarding an acceptable level of lead in toys manufactured for dogs and cats. The standard for children’s products is 600 ppm. The use of a lead-based paint is inappropriate for any toy. Especially red colors tend to contain high levels of lead. In an unrelated lead-contamination story, more than half of 33 brands of women’s red lipsticks tested by the Campaign for Safe Cosmetics contained detectable levels of lead. Apparently not just children and pets are being poisoned. Unfortunately, additional sources of lead contamination will probably be discovered.

Clinical signs of lead poisoning may include gastrointestinal signs such as vomiting, diarrhea, constipation, and abdominal pain. Central Nervous System signs may develop such as intermittent seizures, twitching, and abnormal behavior. Behavioral changes may include irritability, whining, barking, continuous running, and snapping, especially in young animals. Lead exposure may also lead to anemia, anorexia (loss of appetite), and lethargy.

A whole blood sample is the preferred sample for testing. A lead concentration of 35µg/dl or 0.35 ppm is considered to be diagnostic. The presence of a large number of nucleated red blood cells with a packed cell volume of > 30% is considered to be suggestive of lead poisoning.

Pets may actually be the first indicators that there is a toxic level of lead within a household.

Prevention of lead poisoning should include keeping your pets from chewing on painted surfaces, especially red-based paint. Fishing tackle should be secured and placed in an out-of-reach place, and before beginning any house renovations, one should check for the presence of lead-based products.

Treatment consists of removal of lead from the digestive tract with a magnesium or sodium sulfate cathartic. In some cases, surgical removal of a lead object may be necessary. Thiamine given at a level of 1 mg/lb every 12 hours may help alleviate the clinical signs associated with lead poisoning. Chelation therapy using calcium EDTA at a 1% dilution in an isotonic saline or 5% dextrose solution is recommended by treating for two days, resting two days, followed by an additional two days of treatment if warranted. An oral chelating agent that can be used is succimer, also known by the trade name Chemet®, and is available in 100 mg. capsules. Barbiturates may be necessary to control convulsions. The most important preventative is to remove all lead-containing items from the pet’s environment.

References:

Aiello, Susan Editor. The Merck Veterinary Manual. 8^th Edition. Merck and Co. 1998. Pp. 2072-2073.

Ettinger, Stephen. Edward Feldman. “Textbook of Veterinary Internal Medicine.” 5^th Edition. W.B. Saunders Co. 2000. Vol. 1. Pp. 361-362.

“Get the Lead Out”. Pet Age. March 2008. P. 54.