Human silicone wristbands promise passive samplers to check exposure to organic contaminants. However, studying the associated health risks remains challenging because of the latency period for many chronic diseases that take years to manifest in humans. The researchers used silicone dog tags as passive environmental samplers to gather information on daily chemical exposure from dogs, and are delighted with the results.
“Silicone monitors are relatively new, but they are a cheap and effective way to measure exposure to the chemicals we encounter in everyday life – from pesticides to flame retardants,” said Catherine Wise, a PhD student at North Carolina State University and lead author of a paper describing the work. “And we know that many environmental diseases in humans are clinically and biologically similar to those in dogs.”
Wise and other researchers recruited 30 dogs and their owners to wear silicone monitors for five days in July 2018. People wore bracelets while dogs wore tags on their collars.
Researchers analyzed the wristbands and labels for exposure to chemicals in three classes of environmental toxins commonly found in human blood and urine: pesticides, flame retardants, and phthalates found in plastic food packaging and personal care products. They found high correlations between the exposure levels for owners and their pets. Urinalysis also revealed the presence of organophosphate esters (found in some flame retardants) in both owners and dogs.
“What was remarkable about these results was the similar patterns of exposure between humans and their pets,” says study co-author Heather Stapleton, professor and director of the Duke Environmental Analysis Laboratory at Duke University’s Nicholas School of the Environment. “It’s pretty clear that the home environment is a major contributor to our daily exposure to chemical contaminants.”
While dogs and humans can have similar exposures, health effects don’t follow similar schedules – a finding that could help researchers figure out the relationships between chemical exposure and human health. “Dogs are special when it comes to linking exposure and disease outcomes, as effects that can take decades to occur in humans can occur in a dog in one to two years,” says Wise, due to their shorter lifespan.
“People spend an incredible amount of time with their dogs – right now,” said Matthew Breen, professor of comparative oncology genetics at NC State and co-author of the paper.
Dogs provide valuable insights into exposure-related diseases in humans because they have similar exposures at home, have a shorter lifespan, display many clinical / biological characteristics, and have closely related genomes.
“If we can develop ways to correlate canine diseases with their exposures over time, it can give human health professionals an opportunity to reduce those exposures for both species. Dogs are a strong biological sentinel species to human disease. “
The work was supported by grants from the National Institutes of Health, the National Institute of Environmental Health Science, the NC State Cancer Genomics Fund, and the Wallace Genetic Foundation.