Despite the rapid growth in renewables, coal and oil still comprise the lion’s share of global energy consumption. These fuels yield a massive carbon footprint, central to climate change. They also release, into the environment, many tons of heavy metals including mercury, arsenic, lead, aluminum, beryllium, cadmium, chromium, nickel and selenium. Excessive levels of any of these metals are unhealthy. During the past 20 years, my health care group, Manakai, has seen an increase in patients with heavy-metal toxicity and now tests for it more routinely.

To be sure, clean coal technology is being developed in an effort to mitigate the release of environmental toxins, but it is by no means the dominant paradigm. The problem is that what happens on one side of our blue planet affects us all. Last year emerging economies were responsible for 80 percent of the increase in global energy consumption. Heavy-metal residues both in the air and in the oceans diffuse throughout the globe. To be clear, there are natural, ambient levels of heavy metals in the environment, and one would have to include Kilauea, but oil and especially coal substantially increase the environmental burden.

Diet, for most individuals, is the largest source of exposure to heavy metals. Because ahi, for example, are at the top of the food chain in the deep sea, they concentrate mercury and other metals from massive amounts of biomass. It is the same for other large pelagic fish such as ono, mahi and especially marlin.

Greater levels of heavy metals are found in the environment closer to coal-fired power plants and near urban areas, such as Honolulu, where there are a large number of cars. Reef fish, for example, are more subject to local factors including sewage runoff, agricultural toxins and industrial activity. Other immediate sources of heavy-metal exposure include cooking in aluminum pots and certain over-the-counter antacids, and drinking from pipes that contain lead.

Symptoms of excessive levels of heavy metals can be vague. Mercury and/or lead may be associated with memory issues, irritability, anxiety, fatigue, sleep disturbance as well as headache and joint pain. Because each of these symptoms can have many different causes, a careful evaluation is important, and heavy-metal toxicity should be considered.

What to do? First, let’s think of our children’s children and maintain focus on what contribution each of us might make to mitigate pollution and carbon emissions.

Next, let’s be pragmatic about immediate health risks. The American Board of Preventive Medicine advocates reducing environmental exposure. If you eat seared ahi salad for lunch three or more times a week, switch to once. If you are working on reducing red meat consumption, switch it up. Salmon once a week is a good choice, and alternate where your food actually comes from. If the budget permits, local and organic is a healthy choice. Easy on the shore fishing.

If you think you may be at particular risk based on diet, occupation or other suspected exposure, ask your health provider about getting tested for heavy metals. Standard laboratory testing typically looks for mercury, lead, aluminum and arsenic. It is helpful as a screen but is not a good indication of the total amount of heavy metals stored in the body fat. Just like fat-soluble vitamins, such as A, D and E, the more you consume, the more it builds up. Specialty testing is also available, which offers a better sense of how much is stored in the body.

Depending on heavy-metal levels and signs and symptoms of toxicity, at times medical intervention is indicated. One approved treatment is chelation therapy. It was originally developed to treat heavy-metal poisoning from chemical warfare in WWI. It is effective. If considering such treatment, it is important to be well informed on risks and benefits.

Ira Zunin is a practicing physician. He is medical director of Manakai o Malama Integrative Healthcare Group and Rehabilitation Center and CEO of Global Advisory Services Inc. His column appears the first Saturday of every month. Please submit your questions to info@manakaiomalama.com.