Synthetic ETF's - Do they pose a risk? and for whom?

Discussion about the potential risks that may or may not be created for global financial markets by the proliferation of increasingly complicated Exchange Traded Funds (ETF's) that rely on derivatives to achieve their investment objective also highlights the fact that the ETF investors on their part may also be unaware of risks that synthetic ETF structures may pose for their financial security. While ETF's were initially viewed as a simple method to achieve performance targets at little cost and with little risk they turn more and more into instruments that can only be properly scrutinised by experienced investment professionals. Investors should not rely on glossy marketing brochures and sales patter by advisers who are trying to promote the funds.