Threat to Health Raised by Misuse Of Fire Retardant
In the last several years, two chemical compounds at first thought to be a fire safety blessing have caused severe problems with the Michigan environment. The two chemicals are polybrominated biphenyl (PBB) and polychlorinated biphenyl (PCB). Chemically, they are double ring hydrocarbons with some of the molecule’s hydrogen atoms replaced by bromine or chlorine atoms, group VIIA, the halon series.
Halons have the desirable effect of breaking the chemical chain reaction known as fire. They also have the effect of creating a tremendously stable compound, one with an estimated bio-degradable life expectancy of 1000 years.
Both compounds are insoluble in and heavier than water. This makes them almost impossible to recover when misplaced in the environment. PCB, a liquid fire retardant, has long been used as a dielectric fluid for transformers, capacitors and fluorescent light ballasts and also as a paint additive. PBB, a crystalline powder-like fire-retardant substance, is used in manufacturing certain plastics.
While no one in fire safety will dispute the benefits derived from the proper use of these compounds, we must also be concerned with their long-lasting environmental effects. When ingested by animals, both compounds will lock in chemically with fatty tissue. Contaminated fish and animal fats eaten by man will build up this chemical concentration in his system. Farm and laboratory animals have built up PBB and PCB until they became sick, and if continued on the compounds, die.
In 1968, an estimated 1200 Japanese were poisoned with rice oil that was contaminated with the fire retardant PCB. The clinical effects included still births, undersized infants, bone and joint deformities, and various neurological disorders.
The United States Environmental Protection Agency estimates “that about half the American public now carries around with it one to three ppm of PCBs in its fatty tissues.”
An incident involving PBB has caused major concern among Michigan agricultural organizations. In 1973, the Michigan Farm Bureau Services, a profit-making cooperative, accidentally mixed PBB into cattle feed it was blending. The PBB came from Michigan Chemical Company, a subsidiary of the Northwest Industries conglomerate of Chicago. The feed was supposed to contain 8 pounds per ton of magnesium oxide, a trace mineral added to some dairy feeds to increase milk production.
Try to trace contaminant
The magnesium oxide was sold by Michigan Chemical under the name Nutrimaster and was packed in bags identical to those in which the bromine fire retardant was sold under the name Firemaster. Dr. James McKean, a Farm Bureau Services veterinarian, said his agency found Firemaster, instead of Nutrimaster, had been blended into dairy feed. Since the specific contaminant was identified by federal scientists, Agriculture Department inspectors and lab technicians have been working weekends and into the night trying to identify the dairy cows and beef cattle that have consumed the toxic fire retardant.
To make matters worse, feeds blended for chickens, goats, pigs and sheep were also subject to residue from the original mix. To date, over a million animals have had to be destroyed as too sick for human consumption.
What is of concern now is the surviving dairy cows and their milk production, cattle just under the lenient three parts per million federal limit. Farmers faced with bankruptcy have been forced to sell cattle to pay off loans. This meat has been sold to hamburger and hot dog processors, who use more fat in their products than do some other processors. Humans consuming these contaminated meat fats are evidently absorbing the PBB and retaining them in their systems. A study is being made to determine if mother’s milk will be a problem to newborn babies, who will absorb fire retardant from the milk fats.