18 US housing markets where you're likely to live near a 'manmade environmental hazard'

There's a lot to consider when purchasing a home, especially when picking a location. From schools to nearby nightlife, location can make up a large part of a home's appeal, or lack thereof.

RealtyTrac, a real estate analytics firm, has investigated a possibly overlooked element of location: environmental hazards.

The company examined at the prevalence of a variety of undesirable environmental factors - air quality, superfund sites, polluters, brownfields, and former drug labs - for over 7,700 zipcodes nationwide.

They found that nearly a third of all homes in the US are in a zip code with high or very high risk for manmade hazards. Additionally, they found that prices in those high risk areas are typically lower than others.

"The median sales price of homes in high risk zip codes for manmade environmental hazards was $251,106 in 2015 on average, 15 percent lower than the median sales price of $295,202 for homes in zip codes with low or very low risk," said the report.

"Median home prices in high risk and very high risk zip codes were still 1.8% lower than they were 10 years ago on average, even while median home prices in low risk zip and very low risk zip codes were up 5.3% from 10 years ago."

We've taken RealtyTrac's data and compiled a list of the 18 metro housing markets in which at least 95% of the zip codes are in high or very high risk areas. We've also included the median sale price for homes in those high/very high risk areas and their appreciation over the last 5 years.

Check out the housing markets at risk below.