Arsenic in Michigan Well Water

Home Inspector with Diadem Property Inspections - Serving Southeast Michigan

Michigan Well Water and Arsenic

Impurities in well water like pesticides, lead and even radon get a lot of press.

But something else may be lurking in your Michigan well water... arsenic.


arsenic levels in michigan well water

What is Arsenic?

Arsenic is a naturally occuring metal, found in rocks and soil, water, air and plants. It is also odorless and tasteless.

It is also used in industry, most popularly as a wood preservative, but also in paints and dyes, certain fertilizers, as well as mining and coal burning operations.

A compound of arsenic and hydrogen or carbon is called a organic arsenic, and often found in fish or plants. But this compound isn't as dangerous to humans.

Inorganic arsenic, which is arsenic in compound form with oxygen, chlorine, or sulfur, is both much more dangerous to human health, and the type of arsenic found in Michigan's well water.


Dangerous Levels

Ground water sources (like wells) contain more arsenic than surface waters like lakes or rivers. In Michigan, there are geographic "hot spots" that have higher levels of arsenic in the rock formations (see the map).

The Environmental Protection Agency set the arsenic standard for drinking water at 10 parts per billion (it used to be 50 ppb, but was lowered to 10 ppb in 2006) for public water systems. But well water systems are private, and it is up to each well owner to have the water tested for arsenic or other contaminants.

Note that 10µg/L on the map above is read as "ten micrograms per liter" and equals 10 parts per billion. That means Oakland, Lapeer and many of the "Thumb" counties may have well water containing arsenic at over five times the EPA limit.


Exposure and Health Problems

Exposure to arsenic is known to cause both short- and long-term health effects. Short (or acute) effects can occur within hours or days of exposure. Long (or chronic) effects occur over many years.

Short-term effects include:

  • Nausea, vomiting, and diarrhea
  • A "pins and needles" sensation in hands and feet

Long-term exposure to arsenic has been linked to:

  • Decreased production of red and white blood cells
  • Abnormal heart rhythm
  • Blood vessel damage
  • Cancer of the bladder, lungs, skin, kidneys, nasal passages, liver and prostate
  • Thickening and discoloration of the skin
  • Stomach pain
  • Numbness in hands and feet
  • Partial paralysis
  • Blindness

So this is serious stuff we are dealing with.


What Do I Do About This?

For Your Well Water:

Remember that public sources of water are tested regularly. Private sources of water are the responsibility of the well owner.

During well construction and normal water sampling, the water is usually not tested for arsenic. Your local health department can provide a list of certified state and commercial laboratories that for a fee will test for arsenic in your water.


For Your Body:

There are a few medical tests you can have performed, if you are concerned about the level of arsenic in your body, but they are beyond the scope of this post.

What Should I Do If My Arsenic Level Tests High?

In the interim, stop using your well water for drinking and preparing food and switch to bottled water in the short-term. However, for showers and hand washing, you should be fine, since skin contact with water containing arsenic will not result in significant exposure.

If a connection to a public water supply isn't possible, you may want to consider options like reverse osmosis (RO) or distillation. Devices for either method need ongoing maintenance, and RO in particular requires periodic filter replacement.

Water softeners and activated carbon filters do not reduce arsenic levels effectively.

Michigan counties have some great health departments, and they will be glad to answer any questions you have about your well water... or refer you to the right people to speak with.

Posted by


Jason Channell     Twitter - Home Inspection LinkedIn Twitter - Home Inspection

Diadem Property Inspections
(888) 699-8710

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Learn more:

Michigan Builder's License 2101198700
Environmental Solutions Association 3818 -- Certified Mold Inspector & Assessor, Certified Allergen Inspector
International Indoor Air Quality Commission CC1983 --  Indoor Environmental Certified Consultant


Comments (12)

Craig Snead
Quality Home Investments, LLC / Dearborn Heights, MI - Dearborn Heights, MI
Real Estate Investor

Jason, good information. There are still a lot of homes in MI that have well water and should be testing their wells regularly.

Feb 10, 2011 01:16 PM
Robert Butler
Aspect Inspection - Montreal West Island, QC
Montreal Home Inspector | Aspect Inspection

This is a good comprehensive article, well researched. Good job Jason. Geologically arsenic can occur in association with gold so anyone using wells in an area where there used to be gold mines might consider water testing.

Feb 10, 2011 01:58 PM
Juli Vosmik
Dominion Fine Properties - Scottsdale, AZ
Scottsdale/Cave Creek, AZ real estate 480-710-0739

Jason, there were higher than normal arsenic levels in some of the water here in Arizona.  Thanks for the information as it was one of those "typical news" articles saying it was HORRIBLE, but not saying exactly why. 

Feb 10, 2011 03:24 PM
Sheila Newton Team Anderson & Greenville SC
Berkshire Hathaway HomeServices - C. Dan Joyner - Anderson, SC
Selling the Upstate since 1989

Great post Jason, Lots of great info.. isn't it amazing how you can read a list of symptoms and it almost always sounds like you or someone you know?? HA.. I don't have well water so if I have too much arsenic, someone is poisoning me on purpose!!

Feb 10, 2011 03:32 PM
Dale Ganfield
Leland, NC

Hi Jason, great information.  Having grown up in MI's UP and with relatives still across MI, this is important info I will pass on.

Feb 10, 2011 11:25 PM
Jason Channell
Diadem Property Inspections - Serving Southeast Michigan - Troy, MI
The House Sleuth

Craig -- Thanks!

Robert -- Interesting. There's no gold around here, but lots of salt mines in the Detroit area and former copper mines in the Upper Peninsula.

Juli -- Yeah, I guess the "why" always is a good thing to know.

Feb 11, 2011 04:29 AM
Jason Channell
Diadem Property Inspections - Serving Southeast Michigan - Troy, MI
The House Sleuth

Shelia -- The joys of public water! Arsenic is one less thing to worry about.

Dale -- Thanks! My family has a place up in Alpena County, and I have to test the wells every year.

Feb 11, 2011 04:31 AM
Rebecca Gaujot, Realtor®
Lewisburg, WV
Lewisburg WV, the go to agent for all real estate

Jason, some great information and anyone with well water should test them regularly.

Feb 12, 2011 08:22 AM
Jim Frimmer
HomeSmart Realty West - San Diego, CA
Realtor & CDPE, Mission Valley specialist

Just think. Many good murders throughout history have been accomplished by arsenic poisoning.

Feb 13, 2011 01:01 PM
Jason Channell
Diadem Property Inspections - Serving Southeast Michigan - Troy, MI
The House Sleuth

Rebecca -- Thank you. Regular testing is very important. Lots of nasty things, not just arsenic, can be in the water.

Jim -- LOL. I had to think of that old movie, Arsenic and Old Lace, when reading your comment.

Feb 13, 2011 01:05 PM
Not a real person
San Diego, CA

Where did you get such a good map of Michigan’s arsenic area? I should probably jump on the Internet and see what kind of interesting maps are available for California.

Mar 07, 2011 02:12 PM
paul smith
the folks in Mackinaw County could use a lesson on ground water contaminates. they are very uninformed about the dangers of proposed mining operations, and there ground water.
May 20, 2014 01:38 PM