SPECTRE's liquidity pool is a mix of ETH and fiat currency. Your funds are translated into fiat upon deposit, should you choose the on-site accounts, while when you trade from your off-site wallet account you transact solely in ETH. Therefore there is no currency volatility risk on that front. However, when there is a conversion from a cryptocurrency to fiat currencies like USD and vice versa, then you will be subject to exchange rate movements.