Director of Science
We have long been emphasizing the message that in our society today, disinfecting is largely being overdone, with chemicals that are unnecessarily strong. The practice of disinfecting at home has generally demonstrated little to no health benefit and we have expressed concern that the harsh disinfectant chemicals are actually causing health harms.
But we have always maintained – that in exceptional circumstances – like known presence of contagious disease in a location, or for people with compromised immune systems, there can be an appropriate time and place for targeted disinfecting.
And now we have the Coronavirus pandemic – an exceptional circumstance indeed. So, what do we do? And how can we do it safely? We have three main pieces of advice:
- Prioritize the most effective strategies for reducing the spread of the virus.
- Keep your surroundings generally clean
- If you choose to disinfect in your home, choose safer disinfectants where possible
1. Prioritize the most effective strategies for reducing the spread of the virus.
As you have no doubt heard ad nauseum – washing your hands and practicing social distancing are the most effective ways to protect your health. As we currently understand it, the most likely way to get the virus is from direct contact with another person who already has it.
Here’s what we know about handwashing and why it works:
There are really good studies out there comparing classrooms for instance – one with established handwashing protocols and education and one without – and the levels of illness and absenteeism between the two are significantly different. One terrific study examined a host of studies on handwashing interventions in different settings and concluded that handwashing alone can reduce the risk if getting gastrointestinal disease (stomach bugs) by over 30% and reduce the chance of respiratory illness by 20%!
Clearly put – handwashing works. Your hands are the parts of you most in contact with the rest of the world, which can facilitate the transmission of a virus into your body. Washing them off regularly reduces the transmission into your body – resulting in a lower chance of getting sick. And timing your handwashing is key as well – wash your hands as soon as possible after interacting with others – especially if you think someone might be sick. Wash your hands before you eat (when your hands are more likely to come into contact with your mouth). (When you can’t get to a sink easily, using alcohol-based hand sanitizer is also a good option.)
Secondly, practicing social distancing works as well. By far, you are much more likely to get a virus from being in contact with a person who has it – then by picking it up off of a surface that has been contaminated. Breathing in the virus emitted from of a sneeze or a cough of an infected person is a well-known (and unfortunately effective) route of exposure. So by reducing contact with those who are (or might be) sick, and increasing distance from others, you are protecting your health and reducing the chances of the virus spreading in your community – thus protecting the health of others.
2. Keep your surroundings generally clean
Certainly, cleaning and general hygiene are great for your health. Soap and water are amazingly effective at removing both dirt and germs from surfaces. Infectious agents (germs) are attracted to and can survive on dirt and grime that accumulates on surfaces from daily use. (This is why instructions for disinfectants commonly recommend cleaning the surface first.) Soap can actually inactivate viruses like Coronavirus too – by disrupting the fatty membrane that surrounds them. So just cleaning off surfaces with soap (or any general cleaner) can go a long way towards removing a virus from contaminated surfaces.
But do we need to disinfect in addition to regular cleaning in a home to protect our health?
This is far from an answered question. Consider what the CDC says about this:
“Based on what is currently known about the novel coronavirus and similar coronaviruses that cause SARS and MERS, spread from person-to-person with these viruses happens most frequently among close contacts (within about 6 feet). This type of transmission occurs via respiratory droplets. On the other hand, transmission of novel coronavirus to persons from surfaces contaminated with the virus has not been documented.”
But, of course, it appears logical:
We know that if you have a virus on your hands, touching a clean surface can lead to contamination of that surface. And if you don’t have the virus – we know that touching a contaminated surface can lead to contamination of your hands. (Which can also lead to contamination of other clean surfaces you touch.)
We know that viruses (like the current Coronavirus) can stay infectious on various surfaces for hours or days. And we know there are a number of disinfectant chemicals that effectively kill viruses on surfaces. So, if we could use a chemical like a disinfectant to kill all the germs on a surface – this seems like it would prevent illness from spreading.
However, the studies that have tried to measure health benefits (such as lower rates of illness) resulting from the practice of disinfecting on surfaces in homes have had disappointing results. There are no studies, for example, that have shown that using disinfectants on surfaces at home results in any lower rates of illness than from simply cleaning a home with soap and water. One of the best studies showed the opposite – the families in the study cleaning with disinfectant cleaners had just as many instances of illness over the course of nearly a full year of monitoring as the families just using soap and water to clean. It is simply not well established that using harsh disinfectants to kill germs on surfaces in your home actually has any health benefits over regular cleaning with soap and water.
But this doesn’t mean disinfectants are useless. Take hospital settings, for example, where vigilant disinfecting can be a game changer and a life saver. Hospitals contain numerous people with compromised immune systems, numerous infectious agents, and numerous invasive procedures which significantly increase the chance of infection spreading and taking hold. Disinfecting surfaces in operating rooms, for example, can make a huge difference to the outcome. For use in homes of otherwise healthy people however, disinfectants might not make enough difference to be worth it.
Nevertheless, in these extraordinary times, it is entirely understandable that some people – especially those who more vulnerable – or who have close contact with someone with the virus – are going to want to take the extra protective step of disinfecting (in addition to cleaning) as a matter of precaution. Health agencies such as the U.S. CDC have also recommended cleaning and disinfecting frequently touched items in homes.
Descarga la presentación de WVE acerca de COVID-19, los productos de limpieza y tu salud
3. If you choose to disinfect in your home, choose safer disinfectants where possible
The majority of the popular disinfectants found in your average grocery store (or at least until recently when stocks have been largely sold out) contain either quaternary ammonium chlorides (or quats) or chlorine bleach. Both types of disinfectants are potent against a number of different bacteria and viruses. Unfortunately, they both also have some significant drawbacks.
Health Hazards of Quats:
Quats are inexpensive and are potent against numerous infectious agents. But there is reason for concern about the use and overuse of quats:
- Quats are potent skin irritants and can cause rashes and dermatitis.
- Quats can irritate your lungs leading to breathing problems.
- Cleaning workers exposed regularly to quats have developed occupational asthma.
- Quats are linked to reproductive harm, potentially affecting fertility, and possibly leading to birth defects.
- Widespread use of quats is contributing to the global problem of antimicrobial resistance, leading to the development of “superbugs” that cannot be controlled with antibiotics.
Health Hazards of Chlorine Bleach:
- Chlorine bleach is a significant lung and eye irritant.
- Extended chlorine bleach exposure can cause chemical burns on skin.
- It is the leading cause of chemical eye injuries in children in the U.S.. in the category of cleaning products.
- It is also the leading cause of calls to Poison Control for the category of cleaning products, resulting in the greatest number of moderate to severe health outcomes.
Given that the Coronavirus pandemic has and will continue to inspire more frequent disinfecting behavior – the risks of these health hazards occurring will likely rise. We’re already seeing this happen — calls and incidents reported to Poison Control connected to increased cleaning and disinfecting at home are on the rise.
Fortunately, there are alternative disinfectant chemicals that are as effective (or more) in killing viruses and other germs without the same health hazard drawbacks. We are not faced with the choice of quats and bleach or nothing – we do have better options.
Look for disinfectants with active ingredients such as:
- hydrogen peroxide
- lactic acid
- citric acid and
Thus far, several products containing these disinfectant ingredients have been approved for use against Coronavirus by the U.S. EPA. Our colleagues at Beyond Pesticides have created a helpful chart sorting out the safer alternatives that are on the EPA’s “List N” of products approved for use against Coronavirus. You can access it here: https://beyondpesticides.org/programs/antibacterials/disinfectants-and-sanitizers
Keep in mind that this list is not exhaustive, and truly represents our “best guess” at which products are most effective. There simply hasn’t been time (or availability of the COVID-19 virus) to actually test these products for efficacy against this specific virus. In addition, this list is only relevant to disinfectant products currently registered with the U.S. EPA as pesticides. And there are several other disinfecting technologies – such as microfiber cloths, steam cleaners, and UV disinfection – which will likely never be added to the list – because they aren’t pesticides under EPA purview. And we don’t have an official authority to vet these technologies currently – but it’s something that we do as a society need to work on.
Unfortunately, products with the safer active ingredients listed above are very likely to be more difficult to find in stores – especially at the moment. There are major manufacturers producing cleaners with hydrogen peroxide and lactic acid – but they don’t have the shelf space of the more popular quat-based Lysol or Clorox wipes for example.
We need to be asking manufacturers to produce these alternatives – and produce more of them.
So, what can you do in the meantime? Go back to my first two pieces of advice:
- Prioritize the most effective strategies for reducing the spread of the virus.
- Wash your hands and practice social distancing.
- Keep your surroundings generally clean with regular cleaners and water.
- Demand safer alternatives from manufacturers of cleaning products and other types of disinfecting technologies.
Thanks and stay safe!
For more resources on disinfectants:
- See our Quit the Quats page
- Safer Cleaning Practices for the Workplace from MFL Occupational Health Centre (OHC)
- The University of Washington School of Public Health has also published a terrific fact sheet on safer disinfecting, that emphasizes the need for using soap and water, which can be found here.
- Disinfectants and Sanitizers from Beyond Pesticides.
- Guidance from the Western States Pediatric Environmental Health Specialty Unit on Safer Disinfectant Use during the COVID-19 Pandemic.
- To learn more about PAQ, click here.
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