While a professional can always help, there are some common plumbing culprits you can check yourself to see if you can find the sewer gas smell. For example, you should check your water traps, sometimes called P-traps and S-traps, which are located under sink, shower, and laundry drains. The wax ring beneath the base of your toilet, which creates a watertight seal with the plumbing, could also have gone bad.

According to the National Cancer Institute, asbestos-related diseases can take anywhere from 10 to 40 years for symptoms to appear. The health risks increase with prolonged and heavier exposure. Risk factors also include:

• Amount of exposure

• Chemical makeup, size, and shape of the asbestos fibers

• Length of time a person is exposed to asbestos

• Genetic factors 

• Source of exposure (direct exposure or secondhand exposure from someone directly exposed)

Since the EPA partially banned asbestos in 1989, it is no longer used to manufacture new siding in the United States; production had largely ceased by the early 1980s. Many other countries, such as Canada, Iceland, and Denmark, also have bans on asbestos. However, asbestos siding is still present in many homes built before the late 1980s. The only definitive way to know if your siding contains asbestos is to have it professionally lab-tested.

If you own a stereo microscope, you should be able to see the fibers. The stereo microscope often can perform magnification up to 50x. But unless you have experience viewing asbestos fibers, you may not know exactly what you are seeing. Some fibers are curly, while others are long and straight. Blue, brown, white, and gray colored fibers are all possible.