Exchange traded funds (ETFs) have proliferated in the past year but some insiders feel this has gone from ETF evolution to ETF pollution. If surging stocks take a rest, some of the specialty ETFs may not have a future. John Spence of The Wall Street Journal reports advisors and analysts have singled out a few types of ETFs to be wary of. Those with smaller coffers (less than $50 million), thin trading volume, funds tracking similar areas of the market already dominated by others and far-reaching or thematic highly specific ETFs. These are all for instances. The surge of ETFs on the other hand is also proof of a strong and profitable ETF products.





