Pollution Prevention of Cadmium and Other Heavy Metals

The Motivation

Like many heavy metals, cadmium is detrimental to human health. Cadmium can harm renal function, bones, and the pulmonary system. It is classified by the International Agency for Research on Cancer (IARC) as a Group 1 known human carcinogen. Many people consume far more cadmium than they are aware of; almost all humans carry a significant body burden of the metal.

Where does cadmium come from? How are we exposed? And how can we prevent harmful exposures? These are the questions PPRC and our lead scientist, Marjorie MartzEmerson, are seeking to answer.

The Project

Assessing Exposure to and Health Effects of Cadmium

In 2015, we published an initial report, Cadmium: Human Exposure and Potential Effects, which represents a starting point to framing and assessing the risks associated with cadmium exposure, as well as exposure to other heavy metals. The report offers preliminary answers to the following questions:

• How prevalent is cadmium?
• What do we know about its health effects?
• How are humans exposed?
• How can we mitigate risk?

This report led to two important conclusions: Many people are exposed to unhealthy levels of cadmium; and the primary source of our exposure (for non-smokers) can be traced to our food supply. The cadmium in our fertilizer makes its way from our fertilizers to our foods to our bodies.

A Better Understanding of the Source: Fertilizer

In 2017, PPRC published three Frequently Asked Question (FAQ) reports that focus on common questions about the primary source of cadmium exposure: industrially produced fertilizer. The reports are:

• FAQs About Cadmium in Fertilizer: Cadmium Contamination in Plants – This report gives detailed information about the pathway cadmium takes from fertilizers to our food supply. What foods contain cadmium and why? What is the risk to our food supply in the Northwest?
• FAQs About Cadmium in Fertilizer: Fertilizer Laws and Limits – This report provides details about the international and Northwest laws governing the levels of cadmium in our fertilizers and our foods. How protective are the laws in the Northwest? And how can they be improved?
  
• FAQs About Cadmium in Fertilizer: Reducing Cadmium Exposure in Your Garden – This report is for those who like to grow their own vegetables. Does growing your own vegetables protect you from cadmium exposure? What preventative measures can you take?
  

A One Page Summary of Our Findings So Far

If you are a concerned citizen but don’t have time to read the above reports, we’ve published a simple, one-page summary of our findings: Cadmium in Food: Should You be Concerned?

What’s Next?

We will continue to research the risks of and solutions to cadmium exposures and will publish additional materials here. We are looking for partners on both the risk assessment and solutions sides of our research. Want to work with us? Contact us at info@pprc.org.

Additional Resources

On Exposure

• PPRC’s lead scientist, Marjorie MartzEmerson, has also given two presentations on assessing cadmium risks at our 2015 and 2016 Regional Roundtables. Presentations can be found here: 2016 presentation: “Assessing Risks of Heavy Metals in our Foods”; 2015 Presentation: “Cadmium in the Northwest: A Major Public Health Concern?”
• US Food and Drug Administration’s Total Diet Study – Provides info on diet-related exposures to heavy metals and other contaminants.
• CDC-Agency for Toxic Substances and Disease Registry’s Toxic Substances Portal: Cadmium – Bottom line info about cadmium’s health effects.

On Prevention

• The Johns Hopkins Center for a Livable Future’s Soil Safety Resource Guide for Urban Food Growers – Concise guide for urban gardeners looking to minimize harmful exposures
• EPA’s Reusing Potentially Contaminated Landscapes: Growing Gardens in Urban Soils – Fact Sheet on identifying contaminants and reducing exposures in urban gardens