Media are too eager to link silicone to disease

See pp 403, 417

Editor—Legal aid has been granted to a woman who alleges that her child's stomach cramps, skin problems, and food allergies are due to a silicone breast implant. The controversy surrounding silicone breast implants continues despite epidemiological studies finding no connection with neurological and connective tissue diseases.

Use of silicone is common. Some teats of infant bottles are made of silicone (box), and all are lubricated with silicone oil; baby milk formulas contain silicone. Silicone in breast milk is independent of the presence of silicone implants. Ten million bottles of dimethicone (for colic and griping pain) are sold each year.

“Second generation silicone disease” is promoted by a small group of American scientists. Levine et al suggested that a scleroderma-like oesophageal disease resulted from breast feeding by women with implants.1 Their scientific methodology led to many rebuttals.2

Shanklin and Smalley developed a T lymphocyte stimulation test for silicone sensitivity,3 believing that reaction to crystalline silica was equivalent to reaction to silicone. Crystalline silica, a known immunostimulant, is not a component of breast implants. The implant envelope contains amorphous silica; conversion to crystalline silica requires high temperatures and catalysts. They believe, controversially, that silica arises in vivo from degradation of silicone. There is no valid assay for silicone itself

The legitimacy of the test has been refuted in the United States. Shanklin et al have reported that 2000 lymphocyte tests had been performed at $350 per test,4 and their work has been given wide exposure in the media. The media seem eager to seize on any negative information about silicone implants or proponents of it, often allowing little time for an objective scientific response.

In a recent letter to the lord chancellor, four professors (including the chairpersons of the 1992 United States Food and Drug Administration panel and 1992 Canadian government investigation) expressed their dismay that the British legal process may fall prey to unreliable scientific evidence. They reminded him that the United Kingdom Medical Devices Agency's review panel on breast implants has twice concluded that there is no evidence of a connection between breast implants and systemic disease. They warn of the “price paid in North America as a direct result of such … litigation.”