The Environmental Working Group (EWG) is hard at work again, this time taking a look at the chemicals used in both conventional and organic processed foods. EWG is best known for creating the dirty dozen list of fruits and vegetables to avoid and the best sunscreens to use. This new report follows the group's ongoing theme of helping consumers understand what's in the products they buy.

The term processed may have negative connotations, but processed doesn't necessarily mean a microwavable dinner or a bag of chemical-laden chips. Processed simply means something was done to the food after it was harvested or killed. A canister of organic, plain steel-cut oats is considered processed but so is a packet of instant oatmeal with added sugars, flavors and preservatives. The difference lies in how they were processed.

EWG's new report, Organic: The Original Clean Food, reminds consumers that when a processed food is certified organic, it contains no artificial preservatives, colors or flavors. There are also fewer than 40 synthetic substances that organic packaged foods can contain, and those substances must be reviewed by independent and government experts.

However, conventional processed foods can contain artificial preservatives, colors and flavors. They can also contain thousands of chemicals. Most of those chemicals never need to go through a government approval process. The Food and Drug Administration (FDA) relies on the chemical manufacturing companies to declare the chemicals safe.

Loopholes at the FDA

reading food package Not all ingredients in conventional processed foods have been tested by the FDA for safety. (Photo: Nico ElNino/Shutterstock)

The FDA allows two groups of food additives into food without a review by the agency. The first group includes additives that were already declared safe before 1958, when Congress passed a food additives law. The second group includes additives that are considered GRAS, or generally recognized as safe, by either the FDA, a food or chemical company, or a food industry trade association.

According to EWG, about one-third of chemicals and other ingredients allowed in conventional foods have been approved by private parties but not by the FDA. Many of those private parties have a stake in the sale of those substances and pay scientists to review their products. The GRAS designation was intended to cover ingredients that were widely known to be safe, but the FDA created a loophole and allowed manufacturers to declare other chemicals safe. The FDA doesn't look into the data these industry paid researchers create.

For consumers seeking what EWG calls "clean" foods — those made without the use of unregulated chemicals — the report recommends organics because they're "the only commercial option backed by enforceable standards."

The report

What you'll find in the report are tables of synthetic preservatives commonly used in conventional packaged foods but not organic foods. It also lists other substances allowed in conventional foods that aren't allowed in organic foods. The free report can be read online or printed out.

It explains the key differences between conventional and organic regulatory reviews and how any synthetic ingredients approved for use in organic packaged foods are reviewed by independent and government experts. The list of approved substances is reviewed every five years.

Unlike some other EWG reports that look at specific foods or specific brands, this one doesn't recommend specific organic foods. Rather, it's a knowledge-packed summary of information consumers should be aware of so they can make educated choices when shopping for food.

Robin Shreeves ( @rshreeves ) focuses on food from a family perspective from her home base in New Jersey.

Thousands of unregulated chemicals are allowed in conventional processed foods
Environmental Working Group report takes a look at untested chemicals in processed foods and explains what's allowed in organic processed foods.