Poly Brominated Diphenyl Ethers or PBDEs are flame retardant chemicals that are added to consumer products to make them difficult to burn. PBDEs have been around since the 1960s and the levels found in people are 10 to 100 times higher than in Europe. Chemicals like Poly brominated Diphenyl Ethers or PBDEs result from trying to control one thing (e.g. a fire hazard that is minimal, but devastating) and to sell a product. Because PBDEs are added rather than integrated to the product, PBDEs can leave the product and enter the environment, leading to other problems such as learning difficulties, metabolic disease, and cancer. Many other examples of this phenomenon in certain vegetable oils (trans fats), carrageenan (irritable bowel syndrome), mercury (toxic disease), etc. Many of these chemicals are in the water supply and in plastics used every day. PBDEs are organo-bromine compounds used as flame retardants. Like other brominated flame retardants, PBDEs have been used in an array of products, including building materials, electronics, furnishings, motor vehicles, airplanes, plastics, polyurethane foams, and textiles. To read what the CDC has to say about PBDEs, go here.

When fireproofing buildings, various issues with pressed wood and carpeted floors that may contain PBDEs. Fire retardants are added to furniture containing polyurethane foam, including couches and upholstered chairs, cushions and carpet pad. They also turn up in children’s products such as car seats, changing table pads, portable crib mattresses, nap mats and nursing pillows. Some televisions, remote controls, cell phones may also contain chemical retardants. Products made before 2005 may be the most hazardous. Many homes still contain foams from this period. Older foam items contain PVD’s. These toxic fire retardants were taken off the United States and European markets. Newer substitutes such as TDCIPP in infant car seats that may be just as harmful. Logic might suggest purchasing byproducts that are made without fire retardants whenever possible. In the US, most houses are made with wood that contain some fire retardants. Not that Europe is ideal but most houses are made with cemented brick or stone.

The New York Times article “The Mystery of the Wasting House Cats” is a valuable read. Ms. Anthes goes into

the story of an animal endocrine clinic in New York where the veterinarian named Doctor Peterson runs an animal thyroid clinic. He specializes in treating hyperthyroidism in cats. He notes that before 1970, feline hyperthyroidism did not exist. In 2017, his practice involves only treating feline hyperthyroidism; he is not alone. He admits there will never be definitive answers but common research links to common classes of flame retardants that have existed in our homes for decades. If these chemicals are affecting the thyroid hormones of cats, what are these chemicals doing to humans? The article goes into the many behaviors unique to cats. Cats spend a lot of time indoors, eat canned, artificially flavored foods, often sleep on bedding treated with flea control products and spend a lot of time on the floor.

Eventually the research led to a class of flame retardants known as PBDEs. PBDEs have been found to leach from our couches, chairs, cushions and exist in particles of house dust, finally making their way into soil, water, and air. Think of the thousands of couches that are disposed into landfills every day. This is how chemicals with no function in the human body exist in everything from eggs to the fat of whales. One study showed that levels of PBDEs were much higher in the human breast milk in the U.S. compared to Sweden. One must wonder if feline hyperthyroidism problem exists in Sweden.

PBDEs also have a chemical structure close to thyroid hormones and thus mimic and compete with these hormones in the body. The research is clear that these chemicals can alter thyroid function in animals and the human studies are inconclusive. It’s a good guess they have a clear effect. Even though PBDEs have been phased out by the United States and European Union, PBDEs take years to degrade. One thing scientists from the National Institute of Environmental Health Services have found is that PBDEs exist in large quantities in several types of food, particularly seafood flavored canned foods.

Another vivid example of clear human ethical oversight involving animals and humans is in the early 1950s. A Japanese cat disease called “Dancing Cat Disease,” was about cats in Japan that acutely became bizarre and mad all at once. They began to stagger, stumble, convulsing, moving their limbs and salivating uncontrollably. If this sounds all like mercury poisoning, it is; ever heard of “Mad Hatter Disease, Alice?” Finally, six years later, humans suffered from the same symptoms and it affected children. Reportedly thousands of people in Japan fell ill and even died. It wasn’t until 10 years later that a physician identified that methylmercury was being dumped into the water by local chemical plant. By dumping mercury into the water this affects the fish and the animals and humans that ultimately eat them. Most would think a problem of this magnitude would be figured out in months, but it took years.

Similar issues have been found with the food additive carrageenan, which is suspected of damaging the digestive tract. Carrageenan is a common red seaweed thickener in many human and pet foods that has been shown to cause inflammation, irritable bowel disease, and even cancer. For more thorough research on carrageenan, the book “Rich Food Poor Food” provides great insight.

Finally, it is worth mentioning that lobby groups spent 23 million dollars trying to fight bill that would regulate the production of PBDEs. Echoing the current issues of the sugar and tobacco industry. The leading producer of PBDEs worldwide is the United States. Companies that have interest in PBDEs are Chevron, Dow, Exxon and Occidental. Annual global production of PBDEs is estimated to be about 67 metric tons. PBDEs deposits in the United States are found in Michigan and Arkansas. It is interesting that a study of PBDEs in breast milk was the highest in women in Arkansas. California became the first state in 2003 to pass any kind of bill that would regulate certain types of PBDEs. The flame retardant industry argues that the benefits accrued saving lives by fire prevention outweigh the costs incurred by any medical consequences. It is well known that most fires are caused by cigarette smoking indoors.

Sick animals can be a warning of health hazards to humans. It’s probably true that the better we take care of our pets, the better we might take care of ourselves. It’s also a lesson that the further you turn away from nature, the easier it is to fall into disease. I don’t know of a feline hyperthyroidism epidemic in wild cats or other animals. In the hospitals, doctors are seeing an increase in thyroid cancer in humans. We will never know if PBDEs are a risk factor for thyroid cancer, but it’s a good bet. We say the same things about sugar and obesity. Paying more attention to the animals and what they are trying to tell us is a good idea.