This significant discovery was documented in the book Our Stolen Future.
Somehow the plate didn’t look right, so Sonnenschein adjusted the microscope and looked again. His eyes were not playing tricks. The whole plate–every single colony growing in a specially modified blood serum–was as crowded as a subway train at rush hour. Regardless of whether they added estrogen or not, the breast cancer cells had been multiplying like crazy.
In all their years of cell work, they had never seen anything like it. At first, they felt stunned. They didn’t know what to think except that something had gone seriously wrong.
They carefully prepared another batch of plates with breast cancer cells, and once again, the breast cancer cells began mulitplying like crazy. It wasn’t a fleeting event. The mysterious contamination was still somewhere in the lab. They considered every possible explanation from carelessness to sabotage. In the end, the cause proved beyond their wildest imaginings, something even stranger and more unsettling than human sabotage.
When they stored the hormone-free blood serum in some of the test tubes, their breast cancer cells showed an estrogenlike response and multiplied like mad. But the cells showed no response to serum stored in other identical-looking tubes. Although the medical school lab kept ordering the tube number they had used for years, Corning was now supplying a lab tube that had a different chemical composition. When Soto asked about the chemical content of the new resin, Corning declined to disclose the information on the grounds that it was a “trade secret.”
It took months to purify the compound in the plastic that caused an estrogenlike effect in their experiments and do a preliminary identification using mass spectrometry analysis. Finally, they were ready to send a sample of the substance across the river to chemists at MIT for final identification.
At the end of 1989–two years after their detective work had started – they had a definitive answer: p-nonylphenol. Manufacturers add nonylphenols to polystyrene and polyvinyle chloride, known commonly as PVC, as an antioxidant to make plastics more stable and less breakable.
Soto & Sonnenschein found many concerning studies. One found that the food processing and packaging industry used PVCs that contained alkylphenols. Another reported finding nonylphenol contamination in water that passed through PVC tubing. They even discovered that nonylphenol is used to synthesize a compound in contraceptive creams. They also learned that the breakdown of chemicals found in industrial detergents, pesticides, and personal care products can likewise give rise to nonylphenol.
450 million pounds in 1990 in the United States alone and 600 million pounds globally.
Alkylphenol polyethoxylates have been widely used since the 1940s, but in the past decade they have come under increasing scrutiny because of their toxicity to aquatic life, particularly as they break down. By the late 1980s, several European countries had already banned the use of household cleaners of nonylphenol ethoxylates, the compound in this group most commonly used in cleaning products, and similar restrictions are under consideration in their countries as well. While many still allow their use, however, in cleaners prepared for industrial purposes, fourteen European and Scandinavian countries agreed in 1992 to phase out this use by 2000.
A M Soto, H Justicia, J W Wray, and C Sonnenschein
Environ Health Perspect. 1991 May; 92: 167–173.
Department of Anatomy and Cellular Biology, Tufts University Health Sciences Schools, Boston, MA 02111.
Alkylphenols are widely used as plastic additives and surfactants. We report the identification of an alkylphenol, nonylphenol, as an estrogenic substance released from plastic centrifuge tubes. This compound was extracted with methanol, purified by flash chromatography and reverse-phase high performance liquid chromatography, and identified by gas chromatography-mass spectrometry. Nonylphenol induced both cell proliferation and progesterone receptor in human estrogen-sensitive MCF7 breast tumor cells. Nonylphenol also triggered mitotic activity in rat endometrium; this result confirms the reliability of the MCF7 cell proliferation bioassay. The estrogenic properties of alkylphenols, specifically nonylphenols, indicate that the use of plasticware containing these chemicals in experimental and diagnostic tests may lead to spurious results, and these compounds as well as alkylphenol polyethoxylates may also be potentially harmful to exposed humans and the environment at large.