FORTUNE — Labor issues, interest rates and security breaches are among the concerns keeping the top U.S. retailers awake at night.

That’s according to professional services firm BDO USA, which released on Friday its eighth annual look at the top risk factors the 100 largest public traded U.S. retailers named in their most recent regulatory filings with SEC.

Concerns about workforce issues cracked the top-five risk factors for the first time, according to BDO, with 94% of retailers including that factor on their list of risks, up eight percentage points from last year’s study. The study says the retail industry, which is the largest private sector employer in the U.S., is currently staring at the possibility of a jump in labor costs if political leaders act on calls to increase the minimum wage.

President Barack Obama has supported an increase in the federal minimum wage from $7.25 per hour to $10.10. And, this week, fast-food workers across the country went on strike to demand higher wages and the right to form a union.

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Labor concerns finished behind “general economic conditions,” which all retailers listed for the second year in a row. According to the study, this year marked the first time that interest rates took the top spot among specific issues related to the general economy, having been mentioned by 80% of retailers. Fuel prices and unemployment were also among the major economic issues cited.

Other risk factors in the top five are government regulations, competition, consolidation within the retail sector, and concerns over relationships with suppliers and vendors. Consolidation has certainly been prevalent in the retail industry of late, with clothiers Men’s Wearhouse MW and Jos. A. Bank JOSB among the retailers to join forces recently. There has also been a good deal of merger activity among supermarkets, led by Cerberus Capital Management’s $9 billion merger of Safeway SWY with Albertsons.

Meanwhile, the number of top retailers who said they were concerned about privacy issues related to security breaches increased by six percentage points this year to 91%. The jump comes in the wake of Target’s TGT massive cyber security breach last fall as well as the more recent Internet security issues connected to the Heartbleed bug.

Retailers also appeared to be increasingly worried about risks associated with sluggish economic growth, as the U.S. GDP grew by only 0.1% in the first quarter of 2014. The number of retailers who listed economic growth as a risk increased by 22 percentage points from the previous year, to 78%.