Mercury Menace: How Fish and Rain are Bringing Asia’s Pollution to California’s Plate!

Mercury contamination is becoming a growing problem in California, threatening not only the environment but also the health of California residents. The historic mining operations from the Gold Rush era have left behind mercury, which has found its way into water supplies and the food chain. More recently, researchers have discovered that mercury also travels from Asia and is present in rainfall along the coast.

The Dangers of Mercury Contamination

Mercury is a heavy metal that can cause serious health problems for humans, especially if ingested through contaminated food, such as fish. The primary health concern related to mercury exposure is its toxic effect on the nervous system. High levels of mercury exposure have been linked to developmental delays in children, memory problems, vision and hearing impairment, and damage to the brain and kidneys.

Pregnant women and young children are particularly vulnerable to the harmful effects of mercury due to the metal’s ability to pass through the placenta and affect fetal brain development. According to the Environmental Protection Agency (EPA), even low levels of mercury exposure during pregnancy can cause serious damage to a developing fetus and result in long-term neurological problems for the child.

Mercury in the Environment

Researchers at the University of California, Santa Cruz (UCSC) have found that mercury pollution from historic mining operations has leached into water supplies and entered the food chain, threatening the health of California residents. Mercury contamination has long been associated with pollution from abandoned mines in the state, where the heavy metal naturally occurs in rock formations and was widely used during the Gold Rush to extract gold from ore.

However, the UCSC researchers have also discovered that mercury travels over from Asia and is present in rainfall that falls along the coast. This environmental exposure to mercury, especially if individuals consume fish containing mercury, may represent more of an environmental hazard than the mercury fillings in teeth. “People are talking about things like removing dental fillings before cremating bodies (to prevent pollution), but our analyses indicate that this may be a trivial source of mercury compared to the inputs from industrial emissions in Asia,” says Russell Flegal, professor and chair of environmental toxicology at UCSC.

Unfortunately, the problem of mercury pollution from abandoned mines and industrial emissions in Asia is not an easy one to solve. As the mercury contamination continues to spread, it becomes harder to contain and its impact on the environment, wildlife, and human health only grows.

Protecting Yourself from Mercury Exposure

Given the rising threat of mercury contamination in California, it is essential for residents to take steps to protect themselves and their families from exposure. Here are some tips:

  1. Be aware of fish advisories: The FDA provides guidelines on the types and amounts of fish that are safe to eat, particularly for pregnant women, nursing mothers, and young children. It is essential to follow these guidelines to minimize exposure to mercury.

  2. Choose low-mercury fish: Some fish naturally contain lower levels of mercury than others. Opt for fish like salmon, sardines, and freshwater trout, which are known to be lower in mercury.

  3. Properly store and dispose of household products: Many household products, such as batteries, fluorescent light bulbs, and older thermometers, contain small amounts of mercury. Ensure these items are stored properly and disposed of at a designated hazardous waste facility.

  4. Support policies that reduce mercury emissions: Advocate for stronger regulations on industrial emissions and support environmental policies that focus on reducing the release of mercury into the environment.


Mercury contamination is a growing problem in California, and its effects on human health and the environment are becoming increasingly clear. By being aware of the risks and taking steps to minimize exposure, Californians can help protect themselves and their families from this dangerous pollutant. And by supporting policies that reduce mercury emissions, we can all contribute to a cleaner, healthier environment for future generations.