mETAL fact sheets


Arsenic is naturally higher in some of the NWT rivers, lakes and soils because of local geology…

However, through decades of gold mining operations at Giant, Con and Negus mines in Yellowknife, a toxic form of arsenic, called arsenic trioxide in the form of dust, was released into the environment.

In the environment, arsenic is found in two forms:

  • Organic (less harmful); and Inorganic (toxic).
  • Organic arsenic is commonly found in fish and shellfish. 

YKHEMP results found that local fish are safe to eat.

Inorganic arsenic is commonly found in some rice and rice products, seaweed, berries, and some mushrooms.

Some arsenic is found in cigarettes.

SHORT-TERM EXPOSURE – Accidental occupational exposure to an extremely high level of inorganic (toxic) arsenic:

  • Vomiting, abdominal pain and diarrhea.
  • Numbness and tingling of hands and feet.
  • Muscle cramping and death may also occur in extreme cases.

LONG-TERM EXPOSURE – Exposure to arsenic over months, years:

  • Can cause bladder, kidney, liver, lung and skin cancer.
  • Other skin problems include skin lesions (wounds), changes in the color of the skin, and hard patches on the palms and soles of feet. This is currently seen in people who have long term higher exposures to arsenic in drinking water (i.e., in Bangladesh)*.
  • May harm the nervous system and may affect learning in children.
  • May contribute to cardiovascular disease and may affect lung function.

*Current YKHEMP arsenic results show that this is not the case in present day Yellowknife.

  • NWT’s Chief Public Health Officer has recommended to avoid harvesting berries, mushrooms or other plants in areas impacted by industrial activities, and to avoid fishing and recreational water activities in lakes with documented high arsenic levels as part of a precautionary public health advisory
  • If you have an infant, breastfeed if you can. Feed a variety of cereals to your infant, not only rice-based.
  • Have children wash their hands after they play outside.
  • Reduce dust and soil going inside the house (i.e., vacuum front entrance often).
  • Do not burn older pressure-treated wood (manufactured before 2004) and avoid using it for home projects.
  • Check out our Tips to Keep your Arsenic Levels Low booklet for more information.

YKHEMP 2017-2018 baseline study found that, in general, the arsenic levels of participants in Yellowknife, Ndilo and Dettah were lower compared with the rest of Canada. For more information refer to our 2020 Progress Report.

Find more information online at Toxic Substances Portal – Arsenic

Click here for the GNWT Arsenic Fact Sheet


Naturally found in the environment, in air, soil, water, food, and drinking water.

  • Man-made activities like burning fossil fuels, mining, and manufacturing.
  • Batteries, radiation shielding, circuit boards. 
  • Ammunition. Canada has banned the use of lead shot for hunting but lead ammunition is still readily available.
  • Some consumer products like paints, ceramics, caulking, solder and pipes, although these are now very rare.

Lead poisoning is extremely rare in Canada. Children are more susceptible than adults to toxic effects of lead.

Short term (a brief exposure to an extremely high level):

  • Vomiting; Diarrhea; Convulsions; Coma, and death

Long term (exposure over months/years):

  • Development in children
  • Growth and hearing impairment
  • Brain development (intellectual and behaviour)
  • Damage to the nervous system
  • Impaired mental function o Weakness in fingers, wrists, and ankles
  • Small increases in blood pressure and increased risk of anemia
  • Kidney damage
  • Damage to reproductive system
  • Prenatal exposure is linked to premature birth, impaired growth, decreased mental abilities in infants.
  • Use steel, bismuth or iron shot to hunt.
  • Properly dispose of old lead-based paint, leaded gasoline, some ceramics or other lead containing products.
  • Prevent children from chewing or having mouth contact with surfaces that have been painted with lead-based paints.
  • Some make-up or hair dyes could contain lead, keep those products away from young children.
  • Thoroughly wash hands and faces, particularly of children, to avoid contact with potential lead dust or soil on food, dirty fingers, toys, or other objects.
  • Check water pipes in older (pre-1980’s) houses to check if pipes contain lead solder.

Click here for the GNWT Lead Fact Sheet


The main source of cadmium exposure is food, unless you are a smoker.

  • All soils and rocks, including coal and mineral fertilizers, contain some cadmium.
  • Cigarettes and other tobacco smoke.
  • In the workplace (battery manufacturing, metal soldering or welding).
  • Living near burning of fossil fuels or municipal waste.
  • There are low levels in all foods, but highest in shellfish, and liver and/or kidney of some animals such as moose.
  • Drinking contaminated water from untreated lakes, and rivers.
  • Cheap metal jewellery, including some charm bracelets.
  • Rechargeable batteries labelled NiCd or NiCad.

When cadmium enters the body, it is stored in the body for many years. Most of it will be stored in the kidneys. It could:

  • Affect brain development in young children.
  • Damage the lungs and kidneys.
  • Increase risk of lung cancer.
  • Weaken bones.
  • Do not smoke or let children breathe cigarette or other tobacco smoke.
  • Dispose of batteries correctly and keep them out of reach of children.
  • Eat a variety of foods to reduce your exposure to cadmium.
  • Do not let children wear or play with cheap metal jewellery or charm bracelets.
  • If you do any welding or metalworking, ensure your work area is well ventilated and use proper protective equipment.
  • Keep children away from welding fumes and other metal vapours and dusts.

Click here for the GNWT Cadmium Fact Sheet