Pets and Lead Poisoning

by Robin Mosman, Information and Referral Project Officer
NSW Community Lead Advisory Service

It is not widely realised that lead poisoning can pose a significant threat to domestic pets. The potential sources of lead are many and varied, and include electric storage batteries, roofing material, plumbing supplies, bullets, solder, pewter, linoleum, grease, putty, lead foil, toys, improperly-glazed ceramic water or food bowls, and fishing sinkers. However, the most commonly identified source of lead in poisoned cats and dogs is ingestion of lead-based paints.

A recent inquirer to CLAS reported a lead level of 1.6 µmol/L in her dog, high enough to require chelation. The most likely cause seems to be very old paint unsafely removed 13 years ago. Soil underneath the area from which the paint was removed, which was found to have very high lead levels, was disturbed during recent plumbing work, and the dog had been digging in the soil.

Lead poisoning is more commonly diagnosed in younger dogs because they are more likely to chew on objects. However, adult dogs may also be affected. Cats only rarely chew or ingest non-food items, but because of their grooming habits may ingest lead particles that contaminate their fur and paws.

A constant theme over the years in information coming to The LEAD Group has been the identification of elevated blood lead levels in a child showing no particular symptoms, through a pet dog being found to be lead poisoned.

Usually the dog has had noticeable symptoms and been taken to the vet who has tested for blood lead, and warned the parents that if they have a small child they should have its blood lead level tested also. Typically the poisoning is caused by unsafe renovation or repainting.

In a recent case, two babies, aged 7 months and 8 months, the children of friends, were found to have blood lead levels of 27 µg/dL and 17 µg/dL respectively after the pet dog of one of the couples was so severely poisoned it required chelation.

Further fascinating case studies are reprinted below from the article Diagnosis of lead poisoning in dogs by T.S. Koh (1985) Aust Vet J, Vol 62, no 12, p 434, with kind permission of Juoko Koppinen, Editor of Australian Veterinary Journal http://onlinelibrary.wiley.com/doi/10.1111/j.1751-0813.1985.tb14139.x/pdf

Blood lead concentrations, age and clinical signs of dogs that responded to chelation treatment

Dog	Age		Blood lead (µmol/L)	Clinical signs
German shepherd	2 yr		1.6	became aggressive at loud noises; constant barking and hiding in dark areas, for example under house.
Australian cattle dog	8 yr	1.4		change of behaviour; aggressive, constant snapping action.
Terrier	2 yr	1.6		fitting; frothing at mouth
Labrador	4 yr		1.4	nervous; depressed; reacted to noises; phone ringing, door banging and postman’s whistle.
Australian cattle dog	8 yr	1.2		became aggressive .
Corgi	5 mth	1.5		became aggressive with constant barking.
Australian cattle dog	2 yr	1.6		change of behaviour; weight loss; stopped mixing with other dogs
Rottweiler	8 mth	1.4		sudden change of behaviour and became aggressive towards owner.
Pekingese	8 wk	0.9		frothing at mouth and hiding in dark areas.
German shepherd	6 mth	1.0		behavioural change; hyperactive; destructive; snarling at owner.
Australian cattle dog	2 yr	1.3		previously friendly but changed to become aggressive towards people including owner.
Also see: Lead Poisoned Pets and Your Family