Human beings, animals and plants are exposed to many different chemicals from different sources and pathways, and that recent studies indicate that combination effects of these chemicals, including reproductive toxicity and other adverse effects from endocrine disrupters, can have serious negative implications for human health and the environment.
— Council conclusions on combination effects of chemicals 2988th Environment Council meeting Brussels, 22 December 2009 .

2. Ensure pesticides with similar adverse effects have undergone cumulative testing & impose an extra safety factor to take into account additional environmental exposure.

a) Where the same adverse effect (on all major organs/systems) occurs instigate cumulative testing. (Eg. neurotoxic, immune or reproductive effects).

b)  Impose a greater safety margin for assessments - extra safety factor to take account of multiple exposures from chemicals by various routes. The human population is exposed to an endless quantity of chemicals daily, 'chemical stressors'. Current science does not understand if humans are more vulnerable than the animals we test on, nor does it take the needs of more vulnerable sub-groups (eg. children and the elderly) into account. 

It is essential that cumulative testing is flexible, responsive & takes into account the most vulnerable. Today assessments are based on 60kg or 70kg adults.

Pesticides can effect us in different ways - they can increase in human systems to a level where damage occurs, (additive effects), they can work synergistically with each other or cancel each other out to reduce exposure (antagonistic effect), or they can reinforce and increase each others effect - creating more harm than from separate exposures to individual chemicals (synergistic effect).

Perhaps the independent organisation that has carried out the most thorough investigation of cumulative testing practices is PAN Europe.  Pan Europe recommends a cumulative approach on similar effects and - on top of this to account for other chemicals and stress factors, to include an extra safety factor of 10 in risk assessment. Known as the 'UF-mix', PAN Europe notes that the uncertainty factors used in risk assessment (10x10) are an underestimation of the actual risks and do not cover the effects on vulnerable groups like children. 

Unfortunately we cannot look to the international assessment agencies, the WHO and EFSA for independence - their cumulative risk assessment panels are loaded with advisers/lobbyists/representatives from the very industries who produce and sell the pesticides. Very few countries are showing leadership, Denmark stands out. The Danish EPA has encouraged discussion focussed around it's concerns regarding pesticides as endocrine disruptors.

Industry representatives claim narrow differences in Mode of Action (MoA) which leads to pesticides being excluded from cumulative testing. You will see from this IRAC report, table 6.2 page 5, glyphosate is still excluded as an organophosphate. Organophosphates are considered Acetylcholinesterase (AChE) inhibitors. Many independent studies illustrate glyphosate as an AChE inhibitor, yet this published research is excluded by agencies.  It is impossible to properly assess cumulative effects based on adverse effect, until assessment agencies include the independent science demonstrating harm, as per the example of glyphosate still not being considered an AChE inhibitor by the major assessment agencies. 

RITE 10 demands seeks to mitigate this situation.

The most commonly applied pesticide in the world is 'excused' from cumulative assessment. While industry dominates policy establishment this situation will continue. 

With industry exercising so much influence, current CRA panels may not be asking these questions posed by PAN Europe :

....there is much more on cumulative risk assessment than the discussion on chemicals with exactly the same mechanism of action (a tiny fraction of all mixtures). If two chemicals have the same effect (but not the same mechanism-of-action, MOA), it is very unlikely this would not lead to any increased cumulative effect. Additionally, some chemicals are known to give synergistic effects (stimulate each other) and there is no evidence that justifies simply ignoring this phenomenon. Even more importantly, humans are exposed not only to pesticides but also numerous other chemicals, which may contribute to cumulative effects. And finally without a similar MOA and without a similar effect, wouldn’t there be any cumulative effect at all since the body is interconnected through three main communication systems (nerve, immune, endocrine) and shouldn’t the whole issue be looked at from a more holistic point of view? Industry has tried to keep all these questions under the table and managed to get their way for many years
— A Poisonous Injection: How industry tries to water down the risk assessment of pesticide mixtures in everyday food. PAN Europe. Hans Muilerman, René Houkema. 2014

Panels to establish Cumulative Risk Assessment throughout the WHO & EFSA are stacked with representatives with pesticide industry links, rather than independent scientists.


Pesticides industry lobbyists or representatives working within the agencies strive to narrow the MoA - therefore excluding many pesticides from cumulative testing. This is why this work must be carried out  by active, independent scientists, with no financial connection to the final CRA - cumulative risk assessment decision. 

Unfortunately today the 3 agencies are not moving rapidly to respond to the questions raised above. These agencies are not agile or independent, and representation on the CRA panels are heavily biased with many representatives having strong ties to the industry lobby group ILSI (international Life Sciences Institute) or industry itself. :

" took a while for me to to understand that this agency (US EPA), in terms of a Trojan horse, that in fact there was very little difference between corporate interests, interests of the pesticides industry, interests--you know, the mineral extractive industries and what was happening at EPA. And whenever there was a conflict between what was good for industry and what was good for the people, industry almost always won......It's very much a corporate culture. And when I first arrived at EPA, it was not unusual to have someone from Dow Chemical sitting at a desk in the corner in the same office that you were in who was also writing environmental policy. And so, you know, for a while--it took me a while to sort of, you know, get a handle on who was a government official and who was from the private sector in the very office."

Today we have the science available to carry out effective cumulative risk assessment - but not the inclination within the current failing assessment agencies.

Bees & Pollinators

Cumulative testing of pesticides, whether they are herbicides, fungicides and/or insecticides, are not required by the EPA, WHO or European Commission in their pesticide evaluations to insure safety of bees. No neonicotinoid pesticide evaluation held with these agencies includes cumulative assessment of neonicotinoids with other commonly used pesticides - particularly at very low environmentally relevant doses.

The most widely used pesticide in the world - no cumulative assessments?

Roundup is cleverly shelved by the agencies from it's more general 'organophosphate' status into a smaller family: phosphanoglycine. The Agencies maintain glyphosate's 'mechanism of toxicity' is different from all other pesticides.  For years glyphosate was differentiated because scientists used to think it was not a cholinesterase/ acetylcholinesterase (ChE) inhibitor but recent research studies refute this.   (As a potential endocrine disruptor Roundup would be moved into a more dangerous class of pesticides.) Roundup needs to be assessed with other common pesticides, not shelved into a minor class.

This may lead to gaps in knowledge.   '93% of Americans tested by the CDC had metabolites of chlorpyrifos — a neurotoxic insectide — in their urine. Banned from home use because of its risks to children, chlorpyrifos is part of a family of pesticides (organophosphates) linked to ADHD.' [3]  Chlorpyrifos is also an  acetylcholinesterase inhibitor. Glyphosate and Roundup can both have neurotoxic effects.  They are both from the organophosphate family. As of 2014, chlorpyrifos has never been tested cumulatively with glyphosate or Roundup. 

RITE demands that all common pesticides are tested for their toxicological adverse effects. 

Roundup & 2,4-D or dicamba - the next line of GMO defence.

Many scientists believe that 2,4-D and Roundup exhibit neurological toxicity.  New Roundup and 2,4-D resistant GMO plants can have Roundup and 2,4-D sprayed on them.  

But these pesticides have NEVER been tested together to assess cumulative toxicity. Either the active chemicals or in the complete formulas.

Many field studies of farm worker pesticide exposure are rated inconclusive due to the multiple routes of exposure and the wide variety of pesticides used on farms today.  If the cumulative nature of the pesticides farm workers are exposed to were assessed more rigorously, perhaps science could evaluate and reduce/remove the 'toxic mixes'.  The end result may be less worker related disease.

Farmers are anxious about the release of dicamba resistant GMOs - dicamba is extremely volatile - farmers are concerned if their neighbour commence use of these products - they will have no choice as dicamba is easily wind-born and can affect their own crops.

No GMO is tested for the final product the public is exposed to - the modified crop (eg. corn/soy/canola/sugarbeet) with the one, two, three or more pesticide full formulations that are sprayed onto the crop.

The US EPA, WHO & EU place the interests of corporations before the public health interest.


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Pesticides Chemical Structure categories: organochlorines, organophosphates, carbamates, pyrethroids, ureas, azoles, phenylpyrazoles and neonicotinoids.

Preventing Harmful Effects of Multiple Chemical Exposures on Human Health. 2011. A proposal of Pesticides Action Network Europe.

[1] A Poisonous Injection: How industry tries to water down the risk assessment of pesticide mixtures in everyday food. PAN Europe. Hans Muilerman, René Houkema. 2014

[2] EPA Whistleblower Speaks Up About US Corporation Poisoning South African Miners. Dr. Marsha Coleman-Adebayo received her BA degree from Barnard College/Columbia University and her doctorate degree from the Massachusetts Institute of Technology (MIT). She is the author of No FEAR: A Whistleblower's Triumph over Corruption and Retaliation at the EPA.  Real News, October 3, 2014.

[3] Pesticides in Food PAN North America.

[4]  Last dated international agency assessments of 2,4-D and glyphosate herbicides - these result in our recommended ADI/RfD of pesticides. 


US EPA 2005 Reregistration Eligibility Decision 2,4-D
World Health Organisation / FAO 1996 Pesticide Residues in food Toxicological Evaluations 2,4-D.

European Commission 2001 Review Report for the Active Substance 2,4-D. 7599/VI/97-final


US EPA 1993 Reregistration Eligibility Decision glyphosate

World Health Organisation/FAO 2004 Pesticide Residues in food Toxicological Evaluations glyphosate

European Commission 2002 Review Report for the active substance glyphosate 6511/VI/99-final

[5] Glyphosate’s Suppression of Cytochrome P450 Enzymes and Amino Acid Biosynthesis by the Gut Microbiome: Pathways to Modern Diseases Anthony Samsel and Stephanie Seneff.  Entropy 2013, 15, 1416-1463; doi:10.3390/e15041416