Posted June 15, 2016
Four of 320 dogs tested in Flint, Michigan, had blood lead concentrations indicating toxicosis.
Dr. Daniel K. Langlois, an assistant professor at Michigan State University College of Veterinary Medicine, is the lead clinician for a study that involved conducting six screening clinics in Flint. He said the four dogs with lead toxicosis had concentrations of more than 50 ppb, the concentration requiring a report to the state. Up to 20 others had higher than typical concentrations of 25 to 45 ppb.
“When we started testing, it was also several months after the initial news broke, so, at that point, many of these dogs had been transitioned to filtered water, bottled water,” he said.
For comparison, university staff conducted tests on dogs in East Lansing, where few had more than 10 ppb of lead and many had less than 2 ppb, the quantitation threshold of the assay used in the screenings.
About 75 or 80 percent of dog owners in Flint who were surveyed through the screening clinics indicated they had been giving their dogs bottled or filtered water, although not all survey responses had been analyzed by mid-May. Dr. Langlois said the results so far were a pleasant surprise.
||Veterinary technicians draw blood for a lead exposure test this May at the Genesee County Humane Society facility in Flint, Michigan. The Michigan State University College of Veterinary Medicine provided the tests for dogs through six screening clinics. (Courtesy of Emily Lenhard/MSU CVM)
Of the dogs screened through the Michigan State clinics, two had clear clinical signs through behavior changes and seizures, he said.
Dr. James Averill, Michigan’s state veterinarian, said that, including the dogs screened by MSU, the state had received reports of seven dogs meeting the definition for lead toxicosis. He said some cats have been tested, but none had levels meeting the definition for toxicosis.
In February, MSU and the Michigan Department of Agriculture and Rural Development published a guide for veterinarians on lead toxicosis in animals. It is available here (PDF), and it provides descriptions of clinical signs in varied species and recommendations on diagnostic procedures, equipment, and treatments.
The organizations published a separate guide for pet owners.
Dr. Averill said organizations in the state had made substantial efforts to tell people in Flint that they need to take the same precautions for their pets that they take for themselves as well as block pets’ access to unintended water sources by, for example, ensuring toilet seat covers are down.
Dr. Averill also warned that veterinarians who practice in any urban areas with aging infrastructure may want to consider the potential that ailments in animals may be related to metal toxicosis rather than limiting considerations to infections caused by bacteria, viruses, parasites, and fungi.
The city of Flint changed water sources in April 2014, switching from drawing from Detroit’s water system to the Flint River, according to state documents. Residents had higher blood lead concentrations after the change, leading to the October 2015 advisory against drinking the city’s water.
The city’s water treatment plant lacked corrosion control, and lead concentrations in the water increased, according to a report published in January by the U.S. Environmental Protection Agency.
“The river’s water was corrosive and removed protective coatings in the system,” the EPA report states. “This allowed lead to leach into the drinking water, which can continue until the system’s treatment is optimized.”
The city switched back to Detroit’s water in October 2015 and began adding additional orthophosphate for corrosion control in December 2015. Flint’s public water system provides drinking water for about 100,000 people.