top of page


Sterifab: EPA-Registered and Ready to Use

Sterifab™ is the only EPA Registered Virucide, Disinfectant and Insecticide

  • Writer's pictureNoel McCarthy

Understanding Chemicals: What Are Solvents, Active & Inert Chemicals and Why Should You Care?

Updated: May 25, 2022

In today’s contentious and often hostile regulatory climate, it seems as if almost everything can be argued over. Definitions are disputed, research results are regarded with skepticism, and, in some cases, even basic scientific principles have been called into question.

However, there is one thing that almost everyone can agree upon: The plethora of laws, rules and regulations, especially as they relate to chemicals and their use, are extremely confusing. This is especially true when it comes to the often-misunderstood distinction between inert and active materials used in the manufacture of pesticides and other chemical compounds.

The same is true when it comes to the subject of solvents, and their particular role in all of this. But more about that later.

An Important Distinction

The distinction between inert and active chemicals is important because, contradictory as it might seem, toxic chemicals are frequently used as ‘inert’ ingredients in pesticide products. But how can this be? We certainly shouldn't be surprised that the active ingredients in pesticides are sometimes toxic. After all, they’re created with the express intention of killing a wide variety of pests, e.g. bed bugs, lice, mites, fleas, and so forth.

But why are many of so-called inert ingredients actually toxic? And what does that mean for those of us who use these compounds in our offices, homes and places of work?

The fact is that an inert ingredient is any added substance that is not the active ingredient.

Contrary to popular belief, the term ‘inert’ does not necessarily mean that said substance is actually safe.

It only serves to distinguish between the active ingredient(s) in a pesticide and everything else that goes into its manufacture.

What It Means

As a matter of record, the Environmental Protection Agency (EPA) has compiled an extensive list of chemicals that are used as active ingredients and must be disclosed on the label of any product of which they are a part. Plus, the EPA also requires that these substances are subject to tests aimed at establishing their true toxicity.

The big problem here is that ̶ with a single exception ̶ if any one of the listed chemicals is used as an inert ingredient, it is not subject to any form of regulation or control. In other words, “a chemical with known pesticidal properties can be used as an active ingredient or an inert and it will be regulated according to its designation (as an active or an inert) rather than according to its toxicity.”

Some critics contend that this distinction between active and inert materials is not only misleading, but illogical and arbitrary. It’s worth keeping in mind that over twenty years ago the EPA established new regulations governing inert ingredients in pesticides. The aim of the change was “to reduce the potential for adverse effects from the use of pesticide products containing toxic inert ingredients.”

However, the task of identifying these toxic inerts was not wedded to any mandatory regulations and manufacturers were encouraged, but not required, to replace them with less toxic substances.

How successful that effort has been is debatable, but the issue was clearly recognized and some efforts made to correct the situation. The EPA, for instance, has enacted a number of environmental laws regulating hazardous substances. In fact, the sheer number and type of those laws is so extensive that the agency had to create its own Register of Lists (RoL) to guide users.

Why It Matters

So, what does all this mean, from a practical point of view?

Well, to begin with, it means that you have to be very careful how you handle and use pesticides. In fact, you should handle any chemical with care and that goes for even the most (seemingly) harmless household products.

Without alarming you unnecessarily, here is an inventory of commonly used ‘inerts,’ along with a list of some of the problems with which they’ve been associated:

  • o-Cresol - genotoxicity

  • Ethylbenzene - neurotoxicity

  • Toluene - developmental toxicity

  • Butylated hydroxyanisole - possible carcinogenicity

  • Chloropicrin - severe respiratory tract irritation

  • Cristobalite - known carcinogenicity

  • Naphthalene - jaundice

  • o-Phenylphenol- possible carcinogenicity

  • Ethoxylated alkylphenols - endocrine disruption

But this is not merely an academic chemistry exercise, nor a disquisition on obscure regulatory developments.

The Dangers of Inert Ingredients - The Case of Monsanto

Case in point: The recent lawsuits brought against Monsanto, the agrochemical and agricultural biotechnology giant, regarding its widely-used product, Roundup, whose main ingredient is glyphosate.

These lawsuits have been filed by people who claim that they developed non-Hodgkin lymphoma after using the product. The suits contend that glyphosate, along with Roundup’s other inert ingredients, is the chief culprit. However, they also claim that this mixture of chemicals is more dangerous than glyphosate alone. In fact, independent research confirmed that one particular ‘inactive’ ingredient in Roundup, POEA, is highly toxic.

Now, according to Monsanto: “When it comes to safety assessments, no other pesticide has been more extensively tested than glyphosate. In evaluations spanning four decades, the overwhelming conclusion of experts worldwide, including the EPA, has been that glyphosate can be used safely according to label instructions.”

Without becoming embroiled in this or similar disputes, it’s easy to see why this ‘inerts vs. actives’ debate is probably not going to be resolved any time soon.

However, let’s just say that on June 29, 2016, the U.S. District Court for the Northern District of California (Court) issued an opinion which, in essence, "supports EPA’s discretionary authority to determine how to best manage and address any inert ingredients that may cause unreasonable adverse effects on the environment."

Where we go from here is anyone’s guess.

The Role of Solvents

Our main focus thus far has, obviously, been on inert and active components in chemical products like insecticides. But we also have to consider the role of solvents in all of this.

What Is a Solvent, Exactly?

Simply put, solvents are the substances that actually dissolve chemical components and provide us with workable solutions. The term solvent comes from the Latin solvo, which means to ‘loosen’ or ‘untie’, and usually (but not always) refers to a liquid solution.

Solvents are used for a wide variety of purposes: as paint thinners, nail polish removers, in dry cleaning and detergents generally, in perfumes and as spot removers. They are also widely used in the chemical, pharmaceutical, and oil and gas industries.

Generally speaking solvents are defined as either polar and non-polar in nature, but the specifics as they relate to a solvent definition are more technical than most of us would care to know about. Suffice to say that they include such substances as Hexane, Benzene, Toluene, Diethyl ether, Chloroform, Ethyl acetate, Tetrahydrofuran, Acetone, Dimethylformamide, Acetic acid, n-Butanol, Isopropanol, n-Propanol and Ethanol.

Why It’s Important to Know About Solvents

Putting aside the many chemical compounds with which they can be combined, solvents can pose a threat to health and safety just as they are. Commonly used solvents such as diethyl ether and chloroform, which have long been used as anesthetics or sedatives can cause loss of consciousness if inhaled in any quantity.

In fact, some solvents ̶ notably chloroform and benzene ̶ are known carcinogens, while other have been known to damage internal organs like the liver, kidneys, nervous system or even the brain. We should also add that prolonged, unprotected exposure to some organic solvents can produce a range of neurological and psychiatric disorders.

Into all of this we also have to factor the impact that can, and often does, arise from the accidental release of solvents into the environment. As a matter of fact, solvents can migrate long distances and spills and leaks can result in extensive soil and groundwater contamination.

So Is There a Bug-Killing Product You Can Feel Good About Using at Home?

Let me say this. Sterifab is the only U.S. EPA-approved product that is at once a viricide, bactericide, sanitizer, insecticide, deodorant, germicide-disinfectant, mildewcide, fungicide, bacteriostatic and fungistatic.

Sterifab disinfectant spray

What’s more, Sterifab can be sprayed on everything except people, animals, and cooking utensils. It is highly effective at killing bed bugs, getting rid of mites, fleas, lice, ticks, and a host of other insects.

Alas, we cannot divulge the identity and exact percentages of Sterifab’s ingredients, since they are a trade secret.

What we can tell you is that it has been used successfully in an enormous number of locations, from schools, day care centers, hospitals, and homeless shelters to office complexes, animal kennels, hotels, retirement homes, and dormitories, as well as bus lines, police departments and prisons.

In the decades since its introduction, Sterifab has never been the object of any lawsuit, regulatory infringement, personal injury claims or any other complaint.

Nor has it ever been cited by any organization or group as a hazard to public health or safety.



bottom of page