Bioavailable and toxic platinum species present in silicone breast implants ?

Background:
If the findings of Lykissa and Maharaj can be reproduced by others this would have important consequences for medical reasons. While zerovalent platinum is very inert and therefore does not enter into the human metabolic pathway this is different for other valency species of platinum that may be harmful for the human health. Exposure to oxidized platinum species has been associated with asthma, dermatitis, and other allergic responses in sensitized individuals.

Significant amounts of platinum have been found before in silicone breast implants made of PDMS. During manufacturing of this material, hexachloroplatinic acid, a complex platinum salt, has been used as the catalyst for polymerization. Manufacturers claim that they no longer use that particular catalyst. Anyhow, until recently the general consensus was that the platinum present in the gel is in a nonreactive form. Nevertheless, the U.S. Food and Drug Administration has received thousands of reports of adverse health effects from women with breast implants (see for example Wikipedia).


The recent study:
To help settle the debate regarding the health risks, Maharaj, the president and founding director of the nonprofit Center for Research on Environmental Medicine, teamed up with Lykissa, a forensic chemist who founded the testing laboratory ExperTox, to investigate the presence of platinum species in breast implants and their transfer to the body tissues of their carriers.

The study involved 23 subjects, 18 of which had or once had breast implants and 5 of which did not. For those exposed to breast implants, the time of this exposure ranged from 3 to 25 years. The authors collected whole blood, urine, hair, nails, sweat, brain tissue, breast milk, and explants to test for platinum concentrations.

All of the analysis for platinum was performed using IC-ICP/MS. Method development included a quality control check using platinum-spiked samples, which gave them a good recovery (93-100.8%) and detection limit (10-75 pg/g Pt). Moving on to samples from women, the authors found that women exposed to silicone breast implants had platinum levels 60-1,700x for urine, 14x for hair, 3x for nails, and 100x for breast milk compared to non-platinum exposed individuals. But even more shocking, they further found that platinum in explanted silicone breast implant gel occurred mostly in the +2, +4 and +6 oxidation states. Furthermore, tests of whole blood samples found platinum in the [0] oxidation state in control women, but mainly in the +2 and +4 states in women exposed to silicone breast implants.

The debate:
A Washington Post article dated April 7, 2006—a few days after the manuscript was published online—quoted Thomas Lane, a senior chemist with Dow Corning Corp., as saying that “the facts are just not right.” Dow Corning was the biggest manufacturer of silicone breast implants before 1992. In the same article, Michael Brook, a silicone expert from McMaster University (Canada), said the data and conclusions are “hard, if not impossible, to accept.” Brook has served as a consultant for one of the breast-implant manufacturers. Both Lane and Brook have contributed peer-reviewed Correspondences to the recent August issue of Analytical Chemistry (issue 15, pp. 5607–5608 and 5609–5611).

Publication of the Lykissa and Maharaj paper comes at a critical time: FDA is deciding whether to approve applications from two silicone-breast-implant manufacturers, Inamed (now a division of Allergan) and Mentor. Last year, the agency deemed the applications approvable, but the manufacturers have yet to receive the official go-ahead.

FDA is currently reviewing the science in the paper because it has raised enough concerns within the agency, says Pollack. The paper is at odds with the information that is currently on FDA’s website.

The question raised by several scientists about the quality of the science in the current paper are related to:

• poor assignment of Pt valency species in ion chromatogrms based on retention times without analytical standards of the assigned species,
• missing exclusion of possible artifact formation of oxidized Pt species during sample preparation,
• lack of control of contamination of samples during sample preparation,
• very small number of samples and controls.

The only way that this debate can be resolved is by doing additional analytical work on both the silicone implants and on blood samples from women carrying such implants and the necessary controls. The first part of this work on the implants is relatively easy with respect to the number of samples etc. but might be complicated with respect to sample preparation. The second part is more complicated, since the study should include a statistical sound number of individuals that calls for some funding. The analytical methodology applied should give reasonable answers to the questions raised and should respect all the "quality issues" that we have raised before (see Francesconi/Sperling).


The original study:

 E.D. Lykissa, S.V.M. Maharaj, Total Platinum Concentration and Platinum Oxidation States in Body Fluids, Tissue, and Explants from Women Exposed to Silicone and Saline Breast Implants by IC-ICPMS, Anal. Chem.,  78 (2006) 2925-2933. DOI: 10.1021/ac0514016


Related studies:

L.N. Lewis, Platinum-catalyzed hydrosilylation—colloid formation as the essential step, J.  Am. Chem. Soc., 108/23 (1986) 7228-7231.

G. Chandra, P.Y. LO, P.B. Hitchcock, M.F. Lappert, A convenient and novel route to bis(alkyne)platinum(0) and other platinum(0) complexes from Speier’s hydrosilylation catalyst, Organometallics,  6 (1987) 191-2

Kern L. Nuttall, William H. Gordon, K. Owen Ash, Breast Implants and Urinary Platinum, Clin. Chem. (Winston-Salem, N.C.), 40 (1994) 1787. DOI: 10.1093/clinchem/40.9.1787

 M.F. Lappert, F.P.A. Scott, The reaction pathway from Speier’s to Karstedt’s hydrosilylation catalyst, J. Organomet. Chem., 492 (1995) C11-C13.

 Ali El-Jammal, Douglas M. Templeton, Measurement of Platinum in Biomedical Silicones by ICP-MS, Anal. Proc. (London), 32/8 (1995) 293-295. DOI: 10.1039/AI9953200293

 L.N. Lewis, R.E. Colborn, H. Grade, G.L. Bryant, C.A. Sumter, R.A. Scott, Mechanism of formation of platinum(0) complexes containing silicon-vinyl ligands. Organometallics. 14 (1995) 2202-13.

 E.D. Lykissa, S.V. Kala, J.B. Hurley, R.M. Lebovitz, Release of low Molecular Weight Silicones and Platinum from Silicone Breast Implants, Anal. Chem., 69/23 (1997) 4912-4916. DOI: 10.1021/ac970710w

L.N.  Lewis, J. Stein, Y. Gao, R.E. Colborn, G. Hutchines, Platinum catalysts used in the silicones industry, their synthesis and activity in hydrosilation, Platinum Metals Review, 41/2 (1997) 66-75.

 M.R. Harbut, B.C. Churchill, Asthma in patients with silicone breast implants: report of a case series and identification of hexachloroplatinate contaminant as a possible etiologic agent, Israel J. Occup. Health, 3 (1999) 73-81.

 J. Stein, L.M. Lewis, Y. Gao, R.A. Scott, In situ Determination of the Active Catalyst in Hydrosilylation Reactions Using Highly Reactive Pt(0) Catalyst Precursors, J. Am. Chem. Soc., 121/15  (1999) 3693-703.

S. Arepalli, S. Bezebah, S.L. Brown, Allergic reactions to platinum in silicone breast implants, J. Long-Term Effects Med. Implants, 12/4  (2002) 299-306. DOI: 10.1615/jLongTermEffMedImplants.v12.i4.80

 D. Flassbeck, B. Pfleiderer, P. Klemens, Klaus Gustav Heumann, E. Eltze, Alfred V. Hirner, Determination of siloxanes, silicon, and platinum in tissues of women with silicone gel-filled implants, Anal. Bioanal. Chem., 375/3 (2003) 356-362. DOI: 10.1007/s00216-002-1694-z

 S.V.M. Maharaj, Platinum concentration in silicone breast implant material and capsular tissue by ICP-MS, Anal. Bioanal. Chem., 380 (2004) 84-89. DOI: 10.1007/s00216-004-2714-y

Kevin Francesconi, Michael Sperling, Speciation analysis with HPLC-mass spectrometry: time to take stock, Analyst (London), 130/7 (2005) 998-1001. DOI: 10.1039/b504485p

M.A. Brook, Platinum in Silicone Breast Implants, Biomaterials, 27/17 (2006) 3274-3286. DOI:10.1016/j.biomaterials.2006.01.027

Thomas H. Lane, Comments on Total Platinum Concentration and Platinum Oxidation States in Body Fluids, Tissue, and Explants from Women Exposed to Silicone and Saline Breast Implants by IC-ICPMS, Anal. Chem., 78/15 (2006) 5607 - 5608; (Small Correspondence) DOI: 10.1021/ac060759e

Michael A. Brook, Comments on Total Platinum Concentration and Platinum Oxidation States in Body Fluids, Tissue, and Explants from Women Exposed to Silicone and Saline Breast Implants by IC-ICPMS, Anal. Chem., 78/15 (2006)  5609 - 5611; (Small Correspondence) DOI: 10.1021/ac060779g





Related information

U.S. FDA: FDA Backgrounder on Platinum in Silicone Breast Implants
Wikipedia: About Breast implants
Wikipedia: Breast implant controversy



NBC News, Aug. 26, 2004: Breast implants may increase platinum levels
Washington Post, April 7, 2006: Platinum Found in Women With Breast Implants
CNN, August 31, 2011: FDA panels put silicone breast implants back under microscope

last time modified: March 7, 2024