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Pregnancy: Chemicals, Cosmetics, and Radiation


Chemical exposure

Take care during pregnancy to protect your developing baby (fetus) from harmful chemicals.

  • Avoid pesticides, household cleaners, and paint.

    Fumes from these substances can be harmful to a baby, especially in the first trimester of pregnancy.

    Use chemical-free cleaning alternatives while you're pregnant. If you must use chemical cleaners, wear gloves, ventilate the area, and avoid inhaling fumes.

  • Limit your lead exposure.

    Lead may be present in old paint, metal water pipes, and other substances. Lead can cause miscarriage. It can also be passed by a pregnant woman to her baby.

    If you have concerns about lead exposure, talk to your doctor. A simple blood test can find out the amount of lead in your blood.

  • Avoid fish high in mercury.

    Limit high-mercury fish to no more than 150g (5.3 oz) a month. These include fresh or frozen tuna (not canned "light" tuna), shark, swordfish, marlin, orange roughy, and escolar.footnote 1

    Limit some other types of fish, such as white (albacore) tuna to 300 g (10.6 oz) a week.footnote 1

    Health Canada has no restrictions on eating fish and shellfish that are lower in mercury. These include salmon, rainbow trout, pollock, herring, shrimp, mussels, clams, oysters, and canned "light" tuna.footnote 1

  • Think twice about cosmetics.

    There is not very much research about the use of products such as nail polish, artificial nails, hair dyes, and hair permanents during pregnancy. But they all contain strong chemicals.

    It's a good idea to reduce your exposure to these chemicals. If you use them, be sure the room is well-ventilated.

Radiation exposure: X-rays, air travel, and electrical appliances

A single X-ray, such as a dental X-ray, will not harm your fetus. But it's a good idea to avoid unneeded X-rays during pregnancy. Many X-rays can be delayed until after pregnancy.

If X-rays are needed, be sure to tell the technician that you are pregnant. The X-rays can be done with a lead apron that shields your belly.

The radiation from electrical appliances such as televisions, computers, or electric blankets has not been shown to cause birth defects. You can use an electric blanket or water bed heater to warm the bed, but it is a good idea to turn it off when you get into bed so that you don't become overheated.

The amount of cosmic radiation that's considered safe during pregnancy is 1 millisievert (mSv).footnote 2 An occasional airline flight doesn't pose a risk. But if you fly often on business or as an airline employee, you could get more cosmic radiation than is thought to be safe. Be sure to talk about your risk with your doctor or midwife.



  1. Health Canada (2008). Mercury in fish: Consumption advice: Making informed choices about fish. Available online:
  2. American College of Obstetricians and Gynecologists (2018). Air travel during pregnancy. ACOG Committee Opinion No. 746. Obstetrics and Gynecology, 132(2): e533-e534. DOI: 10.1097/AOG.0000000000002758. Accessed November 4, 2020.


Current as of: November 9, 2022

Author: Healthwise Staff
Medical Review:
Sarah Marshall MD - Family Medicine
Adam Husney MD - Family Medicine
Kathleen Romito MD - Family Medicine
Elizabeth T. Russo MD - Internal Medicine
Kirtly Jones MD - Obstetrics and Gynecology