The Pesticide Cocktail Effect

Ingredients:
One- part Thiacloprid (bee and damselfly harming insecticide (1))
Two parts Imidacloprid (insecticide that is toxic to honeybees (2), birds (3)(4) and aquatic life. It can persist in soil for up to three years (5))
Two parts Chlorpyrifos (organophosphate pesticide that can cause developmental issues and damage to children’s brains (28))
A splash of Tebuconazole (fungicide and possible endocrine disrupter (6))
One pear
Method:
Combine Thiacloprid, Imidacloprid, Boscalid and Tebuconazole and spray liberally over pear. Consume and wait for the results to manifest in a myriad of ways!

Jokes aside, the recipe above is not so far from the truth. A disturbing report released in 2019 by the Pesticide Action Network (PAN), outlines what has been termed as the pesticide ‘cocktail effect’. It describes how pesticides become more harmful when combined or, in other words in a cocktail, as opposed to their toxicity when ingested in isolation. The report notes the ‘growing body of evidence’ that reveals the harmful effects of pesticide cocktails on the environment, soil health, insects, waterways, aquatic life, birds and mammals, including humans.

As an environmentalist and a mother, reading this report was deeply concerning. In fact, there was so much to unpack it was difficult to know where to start for this article. I was guided towards concentrating on one aspect that is very close to my heart – the impact the cocktail effect has on one of our most vulnerable populations – our children.

Pesticides and Residue Testing
Many governments, including Australia to a limited extent, test samples of produce to determine if any have exceeded the maximum residue limit (MRL) of pesticides. What the government here and abroad do not do is test for the effects that multiple residues may have when consumed in combination. Most of the studies that have been conducted are by independent academic researchers (7). In fact, I found it incredibly difficult to find any data at all from the Australian government acknowledging they are even aware of the potential hazard.
Our understanding of pesticide cocktails is still in its infancy. However, there is a lot we do know about pesticides and the damage they cause such as:
• It is estimated the number of available pesticides exceeds 70,000 (7).
• According to the CSIRO, inorganic pesticides are often toxic to humans and other mammals (8).
• Animal studies suggest that even moderate amounts of organophosphate (OP) pesticides are neurodevelopmental toxicants, but there are few studies in humans (9) (10).
• According to an Australian study, exposure to pesticides can lead to a range of cancers and other diseases (11).
• Global pesticide use has skyrocketed by 80% since 1990 (12).
• In Australia, the use of agricultural chemicals such as insecticides, miticides, herbicides, fungicides, antibiotics and anthelmintics has doubled since 1992 to over 50,000 tones each year, costing around $3.7 billion (9).
• The toxicity of pesticides is increasing, with some insecticides used today being 10,000 times more toxic than the infamous DDT (13).
• Animal studies show a strong link between exposure to OP pesticides during gestation or the early postnatal period and neurodevelopmental effects (10).

We know pesticides can be destructive to the health of the environment and all living things. The problem is only set to get worse with the increase in available pesticides, the amount we use and the frequency we use them. With 70,000 pesticides available for use, how can we possibly know all the combinations, which of those are safe and which cause harm with devastating outcomes? The sheer volume and breadth of pesticides means we have entered unprecedented territory in understanding the detrimental consequences of their liberal use – now and into the future.

The Cocktail Effect
The report from PAN analyses the current regulatory testing on pesticide residues in the UK. PAN revealed, “over one third of all the fruit and vegetables tested by the UK in 2017 and 2018 contained residues of more than one pesticide” (14).
In 2017, 3,357 samples were taken from fruits, vegetables, dairy, meat and starchy foods. Keep in mind at the time the UK had a population of almost 67 million, which works out to be approximately 0.00005 samples per person, only a fraction of the food consumed in the UK. Of those samples, 26% contained residues of multiple pesticides (15). The 2018 results found slightly less residue in the food overall than 2017, 23.5%, however, the total number of pesticides found was shockingly higher – 110 in 2017 versus 157 in 2018.
Most alarming about these figures is the increase in known, probable and possible carcinogens – 39 found in 2017 (35% of total) to the whopping 63 (40% of total) in 2018. As well as the increase in endocrine disrupting chemicals (EDCs) – 22% in 2017 and 26% in 2018 and developmental toxins, reproductive toxins or neurotoxins – 14% in 2017 and 15% in 2018 (15)(16).

The Findings
Let’s take a look at two popular fruits:
Raspberries. Mums love these delicious superfoods, especially for young children and babies. They’re nutrient dense, pose little threat as a choking hazard and what child doesn’t look adorable with the rosy-red smear of raspberry across their face? The PAN investigation found in total 24 different active ingredients on the samples of raspberries tested in 2017, including herbicides, fungicides and insecticides (15). Within that, one particular sample of raspberries contained:
• 1 known carcinogen
• 1 probable carcinogen
• 2 possible carcinogens
• 2 EDCs
• 1 developmental toxin
• 1 neurotoxin

Another staple of Aussie kids’ lunchboxes and baby foods, the humble pear. Of the pear samples tested, 87.5% were found to contain more than one pesticide residue (14). In 2017 a total of 33 different active ingredients were found in pear samples including herbicides, fungicides and insecticides. These included:
• 7 known, probable or possible carcinogens.
• 5 EDCs

The authorities will tell us that these residues are within the allowable limits, and this may be the case although, it doesn’t seem like something we should be taking our chances with. However, it is important to highlight produce that contained only one pesticide can also contribute to the cocktail effect. When you consider in one meal we may eat multiple food items, in a day even more and over the course of a lifetime an immeasurable amount. Therefore, our exposure is so much more than what those numbers represent. And don’t forget the pesticides we breathe and drink via air and water pollution. Our current testing mechanisms are failing to look at the sum total of pesticides and their toxicology.

What are the Effects of Pesticides on Mothers and Children?
My research led me down a rabbit hole in the quest for information on the toxicology of pesticide cocktails, with almost no data on the effects on mothers and children. Though, I did come across some worrying reports on the harmful effects of pesticides in general on mothers and children. However, this data is by no means complete, with one study reporting the evidence is “poorly understood for links between… [some] pesticides and adverse pregnancy outcomes, although they are known developmental toxicants” (17).

A report from the Committee on Toxicity of Chemicals in Food, Consumer Products and the Environment reported that vulnerable groups of the population, namely pregnant women and young children, may be at a higher risk of harm from the cocktail effect (11). Children may be more susceptible to the effects of pesticides due to increased exposure via food and breastmilk, underdeveloped detoxification pathways, and longer life expectancy in which to develop diseases with long latency periods (16). Not only that, but pesticide exposure is also likely to be more deadly to infants and children. Research conducted on rats looking at the susceptibility to OP pesticides found, “in some cases, the lethal dose in immature animals is only 1% of the adult lethal dose” (10).

Study after study has showed that pesticide residues have been found in placenta, umbilical cords and breast milk (18)(19)(20), is readily transferred to the developing foetus (21), may affect the nutrient pathways from mother to child in utero (20) and has been found in children’s urine (9). The evidence indicates pesticides are prevalent and are readily absorbed by our bodies. There is also a growing body of evidence demonstrating the damage caused by pesticides is long lasting and, in some cases, even fatal.

Renowned environmentalist, scientist, author and regenerative farmer, Charles Massey highlights “when you look at the A’s – autism, ADHD, all the other auto-immune diseases – their take off is a 95% correlation to these chemicals being introduced” (22). The studies are there to back this up. Mexican research on health effects of pesticides found exposure in children is consistently associated with markers of genotoxicity and adverse neurobehavioral outcomes (23). Another study from Mexico that looked at children ages four and five, found those exposed to pesticides showed lower performance in gross motor, eye–hand coordination, draw-a-person, and delayed recall (9). Research examining IQ in seven-year-old children in California found prenatal urinary dialkyl phosphate (found in OP pesticides) concentrations were associated with poorer intellectual development (24).

We often think of Australia as being on the front foot when it comes to the health of our nation. Yet, it seems we are decades behind the rest of the developed world when it comes to pesticide use. Australia uses over 70 pesticides banned in other parts of the world such as the EU and the USA (13). One of those is Chlorpyrifos, a diethyl phosphate pesticide deregistered in many places because it is linked to developmental issues and damage to children’s brains (25)(26) and readily transfers to breastmilk in animals (27).

As a nation we are struggling with an obesity crisis with one quarter of Australian children being diagnosed as overweight or obese (28). In a nasty twist of fate, changing our diets to reflect the recommended consumptions of fresh fruit, vegetables and protein rich foods actually “increases the pesticide toxicity footprint compared to the current average diet” (11). On one hand our diets from an early age are lacking in fresh fruit and vegetables but it is these same foods that are the most affected by pesticide toxicity (29) and make us more vulnerable to the pesticide cocktail effect.
How do our children stand a chance when their exposure to toxic chemicals begins before they even enter the world and continues throughout their lives?

Residue testing in Australia?
In order to understand the effects of pesticides on mothers and children, it felt important to find out more about how Australia tests our food in the first place.
In 2013 the Labor government established a $25 million pilot program to monitor pesticides in Australian fresh produce. By the following year, new Agriculture Minister for the Coalition, Barnaby Joyce, scrapped the program. This was despite the fact the program identified shortfalls in the monitoring of pesticides in Australian food and authorities admitting they have “little information” about the extent of their persistence and what harm they are causing to health and the environment (13). The pilot program also found samples of strawberries MRL 90 times the acceptable amount (30) and samples of grapes to have pesticide MRL 200% above the safe daily limit for children (13).

Surely this is a job for Food Standards Australia and New Zealand (FSANZ)? Well, according to a report by The Guardian, the last comprehensive survey of pesticide residues in Australian food for domestic sale by FSNAZ was published in 2019, using the same data collected in the 2013 pilot program (13). So, who is in charge? Trying to figure out who is responsible for regulating pesticides in food and in the environment seems to require investigative skills Sherlock Holmes wouldn’t even be able to live up to. In another report by The Guardian, they “counted at least 15 agencies involved” (31).

It is true Australia does from time-to-time review chemicals used in farming and even deregisters those that pose a significant threat, such as DDT. However, many reviews of these chemicals can take decades, with some that are still in use today having been under review since the 1990’s (32).
It seems like all we are left with is a snapshot in time of pesticide levels in Australian food rather than ongoing monitoring.

Introducing “Big Chem”
You may not be surprised to read, Joyce instead redirected some of the funds ($8 million) towards “improving farmers’ access to agricultural chemicals” (30).
Just like we’ve been exposed to the powers of “Big Pharma” over the last few years, it appears the Australian government have their hands deep in the pockets of Big Chem too. In an interview with Charles Massey, he details how “global agricultural chemical companies run very sophisticated marketing and sponsorship networks that reach into almost every facet of rural life” (33).

Big Chem companies such as Bayer and Australian company Nufarm, contribute millions, if not billions of dollars, in support for rural activities. They even fund government bodies, including – most controversially – providing 90% of the budget for Australia’s pesticides regulator, the Australian Pesticides and Veterinary Medicines Authority” (33). The testing that is undertaken is self-regulated and monitored via Fresh Markets using Freshtest whereby farmers have to pay to have their produce tested and the results are not publicly available (34) and does not account for the farmers that sell directly to businesses (31).

I don’t know what I find more disheartening, the actual information or the fact it no longer shocks me. Not only does the Australian government not test for the cocktail effect of pesticides, but they also use a shady system whereby those testing and setting MRLs are funded by those providing farmers with the pesticides they are testing.

What can we do to protects our children?
We don’t know enough about what the pesticide cocktail effect is doing to us and our children, but it can’t be good given the links pesticides have to a host of ill health outcomes. Looking at individual chemicals rather than the cocktail of chemicals seems irresponsible, one hell of an oversight by the regulatory bodies and ignores the potentially toxic health risk to all forms of life.
Sadly, as PAN argues, it may be impossible to create a monitoring system sophisticated enough to be able to evaluate, interpret and measure the potential hazards of the pesticide cocktail effect. Moreover, the quantity of the pesticides used is not necessarily a useful indicator of the potential toxicity impact. Individual active ingredients vary in fate, exposure, and effect once emitted into the environment (11) and when used in combination (14). As Murdoch University grain residue specialist, Associate Professor Rob Trengove states, “what someone can eat and have absolutely no problems [with] may cause some health issues for other people (31).”

With little to no comprehensive understanding of the cocktail effect, it is challenging to integrate this type of information in a meaningful way across the extensive population. We are essentially walking into this completely blindfolded.

The Precautionary Principal
I’m writing this article from the other side of the world, well into the depths of winter. Our garden has succumbed to many frosts and below zero temperatures where the only produce it has to offer at present is cabbage and kale. Many other mothers of young children will understand the daily struggle it is to get our kids to eat any vegetable, let alone two brassicas! So, with the dwindling supply, for now I must supplement our fruit and vegetable intake with store bought fresh produce.

As I browse the shelves of my local fruit and vegetable store, I rejoice in the opportunity to shop plastic free, as many locally run fruit and veg stores proffer. But each time I reach for an item I’m burdened with the knowledge researching this article has gifted me.
My thoughts send me off into a reverie – I muse about living in a world where buying food from any shop or supermarket means we are buying organic produce, grown by agroecological practices. Oh the freedom that would bring to our thoughts – to be able to unconsciously purchase food without it bringing on a wave of anxiety about the damages it may cause to our families now and decades into the future.

Whilst this article did not achieve what I had set out to do and my research fell short of the objective – to understand more about and expose the harm caused by the cocktail effect in Australian food – I choose not to end this piece on a pessimistic note. It seems the only option we have to protect our children, ourselves, the environment and bring us closer to an anxiety-free grocery shop experience is to abide by the precautionary principle and proceed with vigilance.

Here are some actionable steps to take:
• Do not rely on the government and its weak regulatory systems to safeguard your family from pesticide poisoning.
• Do grow your own food.
• Do purchase from local producers that grow food to agroecological principles.
• Do lobby the government to do better.
• Do your own research and become empowered with knowledge.
• Do start conversations around food and be an advocate for our children and their future  
References

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