Bacteria Levels in Water

Bacteria may be found in well water.  This can occur if a well is not properly constructed and sealed, or if the ground water itself has been contaminated.

Are bacteria harmful?

Many types of bacteria cause disease.  Bacteria from human or animal waste are the most harmful.  Drinking well water which has been contaminated with bacteria can result in stomach cramps, diarrhea, and other health problems.

What can you do?

Have your well water tested regularly.  Testing for harmful bacteria is done free-of-charge at the Provincial Health Laboratory.  You can pick up sample bottles from the lab, the Peterborough County-City Health Unit, or municipal offices.

At the lab, the sample will be tested for coliform and E. coli bacteria.  If these are found, do not use the water for drinking, preparing juice or infant formula, washing fruits and vegetables, or brushing your teeth.  To make water safe, boil it for one full minute, or treat it by another method to kill the bacteria.  Carbon filters do not remove these bacteria. 

Until the problem has been corrected, use an alternate safe water source for bathing infants.

For more information about treating water to kill bacteria, and for advice on how to prevent contamination of your well, contact a Public Health Inspector, or pick up a free copy of How Well Is Your Well? at the Peterborough County-City Health Unit. 

Fluoride Levels in Water

Fluoride is a mineral found in rocks and soil.  Your well water may contain naturally-occuring fluoride.  Drinking water which contains fluoride has a protective effect on tooth enamel.

Is fluoride harmful?

Drinking water with levels of fluoride which are too high can lead to dental fluorosis, a condition which causes discoloration of the teeth.

Generally, fluorosis is not a health risk; however, it may be unattractive.  In severe cases, the teeth may become pitted, and require treatment by a dentist.

What can you do?

Have your well water tested by an accredited laboratory.  Sample bottles are provided by the lab, and there is a fee for testing.

If results indicate that fluoride levels are too high, have a second test performed.  If the fluoride level is confirmed to be over 1.5 milligrams per litre, or 1.5 parts per million, use an alternative drinking water source such as bottled water, or a treatment system such as reverse osmosis or distilling.  Most other filtering systems do not remove fluoride.

Discuss fluoride supplements with your dentist or doctor or call the Health Unit.  You can also check the website for the Canadian Dental Association (CDA) for more information.

If you have any questions or concerns, contact Dental Services at the Peterborough County-City Health Unit (705) 743-1000.

Nitrate Levels in Water

Nitrates are chemicals that occur naturally in soil and rock formations.  Nitrates get into ground water from decaying plant or animal material, manure, fertilizers, or septic systems.  Generally, the level of nitrates in the ground water is low, however runoff of ground water can affect the water in your well.

Nitrates can be found in wells regardless of the type of construction, and the nitrate levels can vary according to the location of your well.  Eliminating the source of nitrates for an individual well can be difficult.

Are nitrates harmful?

High levels of nitrates in water used for drinking and cooking cause a condition in infants called well water cyanosis.  This is sometimes called blue baby syndrome because the blood's ability to carry oxygen is affected, and the baby's skin turns a dark shade of blue or purple.  Infants under six months of age lack enzymes which protect against blue baby syndrome, and are at risk if given formula prepared using water with high levels of nitrates.

Breastfed babies doe not get blue baby syndrome unless they drink unsafe well water.  Expectant mothers can drink well water that is high in nitrate content without harming their unborn babies.

Ordinary carbon filters, water softeners, and boiling or chlorinating water do not remove nitrates.  In fact, boiling water increases the level of nitrates - the water evaporates leaving harmful elements behind.

What can you do?

If you are pregnant, or have a baby, have your well water tested for nitrates by an accredited laboratory.  Sample bottles are provided by the lab, and there is a fee for testing.

If your water test has nitrates over 10 milligrams per litre, or 10 parts per million, use an alternative drinking water source such as bottled water, or a treatment system such as reverse osmosis or distilling.

Never give well water to a baby under six months of age, or mix infant formula with well water that has not been tested and found safe for nitrates.  Breastfeed your baby if at all possible.

For nitrate and fluoride testing, contact:

>  Caduceon Laboratories,
    748-1506
    160 Charlotte Street
    Peterborough, ON

>  SGS Lakefield
    652-2000
    185 Concession Street
    Lakefield, ON 

Information pamphlets are available at the Health Unit.  If you have any questions about fluoride or nitrates in water, or fluoride supplements, call the Health Unit's Dental Program at (705) 743-1000. 

TTY:  (705) 743-4700