Mercury and pregnancy safety

Human exposure to mercury comes through the air and the diet. Exposure threatens male and female reproductive health and poses profound neurological risks to a developing fetus. The blood level of mercury in a fetus can be higher by volume than the mercury level in its mother’s bloodstream.

Atmospheric exposure can come from waste incinerators that burn medical waste, fluorescent light bulbs, and batteries. Facilities that burn oil and coal emit mercury into the air. People working at dentists’ offices are more exposed to mercury on the job than people in most other professions.

Bacteria in the sea break down environmental mercury which is then eaten by algae and subsequently by the fish who feed on the algae. Carnivorous fish at the top of the marine food chain, including pike, shark, swordfish, and tuna, are common sources for human dietary exposure to mercury.

The effect on fertility and pregnancy

The long-term effects of mercury poisoning have been clearly documented as a result of two major epidemics in the mid-20th century. One event occurred in Japan, the other in Iraq.

Studies using mice demonstrate how mercury stops cell division in the middle of the process and interferes with cellular migration. It binds to DNA, causing interference with chromosome copying and protein production vital to a developing fetus.


  • When partners are exposed to mercury on the job, they can bring its toxic effects home to their families. The risk of spontaneous abortion is twice as high for people whose partners are exposed to mercury on the job than the risk to women in the general population. 



  • Cerebral palsy
  • Mental retardation
  • Weakness of the muscles and reflexes
  • Seizures
  • Visual impairment
  • Delayed mental development

To Minimize Exposure

  • Avoid eating the fish most likely to be contaminated.
  • Eliminate exposure in the workplace if at all possible.

< Common Household Chemicals

Source: Chalfin, Noah. “Reproductive & Developmental Hazards: Spotlight on Mercury.” Center for Ethics and Toxics (CETOS). Environmental Commons. n.d. Web. Dec 4, 2013.