The PIP scandal: an analysis of the process of quality control that failed to safeguard women from the health risks

Chemical composition of breast implants

The significant component of breast implants is silicone (polydimethylsiloxane), not to be confused with the chemical element silicon. Although silicone does contain silicon, the former does not occur in nature and is entirely synthetic. Due to the production method, commercial silicone products will contain variable concentrations of molecular weights and sizes including a subgroup of small-sized molecules referred to as D4, D5, D6.4,5
In addition, the normal manufacturing process may result in traces of platinum, used as an essential catalyst. Small traces of platinum may be an acceptable find in medical grade silicone, unlike heavy metals such as tin, zinc, chromium, arsenic, lead, antimony, nickel or copper. In addition to specific health concerns associated with these heavy metals, there is also the risk that they may induce platinum toxicity.6,7 Traces of lead and zinc were reported in the PIP implants but these were within permitted regulatory levels. A more detailed chemical analysis of the gel is still ongoing.

Our concerns

The PIP implants were found to contain a higher proportion of small-sized molecules D4, D5, D6 than the norm.8 D4 (octamethylcyclotetrasiloxane) was identified as an endocrine disrupting chemical (EDC) of ‘high concern’ in 2007 by a report commissioned by the European Commission entitled ‘Study on enhancing the Endocrine Disrupter priority list with a focus on low-production chemicals’.9 The effects of low doses of such chemicals, particularly on the developing fetus, have been well documented.10⇓⇓–13 While most regulatory levels of impurities in breast implants are considered acceptable in the range of a few parts per million, Le et al.14 showed that EDCs are capable of affecting developing neurons in vitro at concentrations of less than one part per trillion. Considering these known risks and the fact that most women receiving breast implants were of reproductive age, we would expect the MHRA and the Department of Health to fulfil its duty of care and thoroughly investigate these risks as well as provide full information to patients.Read more