Honey, a complex mixture of sugars, amino acids, phenolics and other compounds, has been valued for its medicinal properties since ancient times. Made from flower nectar and produced by bees, honey's medicinal properties vary depending on what type of flowering plant it comes from.
One of the most heavily researched and renowned is Manuka honey, which is produced from certain Manuka plants — also known as tea trees — of the Leptospermum species, which are native to New Zealand and Australia.1
Manuka honey is a high-value export in New Zealand, one that prides itself on being a pure, high-quality product. "Our reputation for honey production and export rests on the integrity of our products and the credibility of our systems," wrote New Zealand's Ministry for Prime Industries (MPI).2
Tests by the agency show, however, that even natural Manuka honey is being affected by environmental contaminants — namely the herbicide glyphosate.
Glyphosate Detected in New Zealand Manuka Honey
Glyphosate is most commonly known as the active ingredient in Roundup herbicide, but it's found in about 90 different products. Overall, glyphosate is the most used herbicide in the world, including in New Zealand.3
New Zealand Food Safety has been testing honey samples for agricultural compounds, including insecticides, fungicides, herbicides and other environmental contaminants for years, but in 2017/2018 and 2018/2019, they tested honey samples for glyphosate residues, some of which turned up positive.
In their "National Chemical Residues Programme Report" released January 2020, it's noted that 300 raw extracted archival and retail-packed honey samples were tested for glyphosate residues during 2017/2018, while another 60 retail-packed Manuka honey samples were tested for the herbicide during 2018/2019.4
Out of the 300 samples, 22.3% contained glyphosate residues above the laboratory limit of reporting, with clover or pasture floral types testing positive more often than other varieties. About 1.7% of the unblended or unprocessed (raw extracted) honey samples contained glyphosate residues at levels above the regulatory limit.
Among the 2018/2019 retail samples tested, 18.3% contained glyphosate residues, though they were below the regulatory maximum. As for where the glyphosate contamination came from, the report noted:5
"Based on reported honey types, the most likely cause of the residues in honey is attributed to unintended exposure of honeybees to glyphosate from its approved use in agriculture.
This causal attribution is in comparable with previous international reports. As a consequence, beekeepers have little practical means of excluding bees from foraging on plants treated with glyphosate.
… To do so, would require the beekeeper to place their hives at the centre of 28 square kilometre area where they had assurance from land owners and managers there was no agricultural compound use."
Glyphosate Residues Pose 'Possible Trade Risk'
New Zealand's health officials maintain that no health risks are posed by the glyphosate residues detected in the honey, but a ministerial briefing document obtained by 1 News labeled the contamination a "possible trade risk … because most countries importing honey from New Zealand have no maximum residue limit (MRL), generally meaning that residues must not be detected at any level."6
Further details revealed in the confidential briefing suggest that a honey producer in New Zealand began investigating glyphosate residues in 2018 after the chemical was revealed in its honey by a retail market overseas. According to 1 News:7
"'Their investigation into the detections found residues present in unprocessed honey at levels above the New Zealand default maximum residue limit,' it reads. 'Their investigation concluded the likely cause of the residues was the use of glyphosate in pasture renovation/renewal.'"
New Zealand Food Safety reiterated that the glyphosate-contaminated honey posed no food safety concerns, adding:8
"For context, a 5-year old child who was consuming honey with 0.1 mg/kg of glyphosate residues (the default maximum residue level in New Zealand) would need to eat roughly 230kg of honey every day for the rest of their life to reach the World Health Organization Acceptable Daily Intake for glyphosate."
However, critics said that even at low levels, glyphosate residues mean the honey is tainted, and not due to the fault of the beekeepers, but to lax environmental regulations.
"If New Zealand wants to be a cheap commodity producer, producing tainted food, then that's New Zealand choice, or we can actually have stronger regulation, which protects our free market," Jodie Bruning of the Soil and Health Association told 1 News.9
Glyphosate Detected in Honey Samples Worldwide
Glyphosate has been detected in a variety of honey samples tested worldwide, including that taken directly from 59 beehives on the Hawaiian island of Kauai. There, glyphosate residues were found in 27% of honey samples, at levels as high as 342 parts per billion (ppb).10 Honey was also detected in 33% of honey samples purchased from stores on Kauai.
Not surprisingly, glyphosate occurrence and concentrations were higher in samples taken from the western, predominantly agricultural half of Kauai. Agriculture land use was strongly associated with glyphosate concentrations in honey from hives nearby, as was having extensive golf courses or highways nearby (glyphosate is not only used in agricultural areas, but also on golf courses and roadsides).
In 2014, researchers also found glyphosate in 45.5% of honey samples labeled organic, while the Canadian Food Inspection Agency found glyphosate in 29.7% of 3,188 food samples tested.11 Likewise, the U.S. FDA began a limited testing program for glyphosate in 2016, in which high levels of glyphosate were found in oatmeal products and honey, but the agency did not release the results publicly.
Internal FDA emails obtained by investigative journalist Carey Gillam through Freedom of Information Act (FOIA) requests reveal Roundup has been found in virtually all foods tested, including granola and crackers.12 In 2016, Gillam wrote:13
"All of the samples the FDA tested in a recent examination contained glyphosate residues, and some of the honey showed residue levels double the legally allowed limit in the European Union, according to documents obtained through a Freedom of Information Act request.
… In the records released by the FDA, one internal email describes trouble locating honey that doesn't contain glyphosate: 'It is difficult to find blank honey that does not contain residue. I collect about 10 samples of honey in the market and they all contain glyphosate,' states an FDA researcher."
Glyphosate Is Widespread in the Food Supply
While New Zealand Food Safety suggested a child would have to eat huge amounts of honey daily to even come close to consuming the amount of glyphosate deemed risky by the World Health Organization, this doesn't take into account how ubiquitous this chemical is in the environment.
Honey is unlikely to be a person's only source of exposure, as glyphosate has been detected in a wide variety of commonly consumed foods.
For example, the Environmental Working Group (EWG) commissioned three rounds of glyphosate testing on cereals and other foods sold by Kellogg, General Mills and Quaker, the latest of which took place in 2019 and involved 21 oat-based cereal and snack products.
The chemical was found in all 21 products, with all but four of them coming in higher than EWG's benchmark for lifetime cancer risk in children, which is 160 ppb.14 Glyphosate has also been detected in PediaSure Enteral Formula nutritional drink, which is given to infants and children via feeding tubes,15 to get an idea of just how widespread it is.
It's also found in air, rain, municipal water supplies, soil samples, breast milk, urine, organic plant-based protein supplements and even vaccines, including the pneumococcal, Tdap, hepatitis B (which is injected on the day of birth), influenza and MMR vaccines.16,17
Even Low Levels of Glyphosate Pose a Risk
The International Agency for Research on Cancer (IARC) identified glyphosate as a probable human carcinogen in 2015,18 and in the U.S. about 125,000 claims have been initiated by people who believe exposure to Roundup caused them to develop Non-Hodgkin lymphoma.19
Research published in Frontiers in Genetics also supports glyphosate's cancer link, finding that exposure even in low concentrations (in parts per trillion) may induce cancer in cells when combined with microRNA-182-5p (miR182-5p).20
MicroRNA-182-5p is a gene regulatory molecule found in everyone, and overexpression of the molecule has been linked to cancer. Michael Antoniou of King's College London, who peer reviewed the study, stated, "These observations highlight for the first time a possible biomarker of glyphosate activity at the level of gene expression that could be linked with breast cancer formation."21
Aside from cancer, significant bioaccumulation of glyphosate has been documented in the kidney, an organ with known susceptibility to glyphosate, and glyphosate-induced kidney toxicity has been associated with disturbances in the expression of genes associated with fibrosis, necrosis and mitochondrial membrane dysfunction.22
Further, research published in 2015 found that glyphosate in combination with aluminum synergistically induced pineal gland pathology, which in turn was linked to gut dysbiosis and neurological diseases such as autism, depression, dementia, anxiety disorder and Parkinson's disease.23
Bayer Proposes Roundup Lawsuit Settlement
A number of animal and human diseases have been rising in step with glyphosate usage. This includes conditions such as failure to thrive, congenital heart defects, enlarged right ventricle, liver cancer and, in newborns, lung problems, metabolic disorders and genitourinary disorders.24
The environmental risks are also immense. Speaking to Politico, Jeroen van der Sluijs, a professor of science and ethics at Norway's Bergen University, explained:25
"It [glyphosate] kills a lot of non-target plants and it leads to an agricultural practice where you have monoculture with no wild plants left in the fields … If you remove all the wild plants from the fields then you only have the crop that flowers and that's only a very short period in the year. The rest of the year there's nothing to forage on.
… We find [glyphosate] everywhere in surface waters, it is indeed toxic for all kinds of aquatic organisms, so of special concern are amphibians like frogs and salamanders."
Bayer, which acquired Monsanto, Roundup's original maker, in 2018, has been in settlement talks for months to resolve the litigation but continues to deny that the chemical causes cancer. In June 2020, they reportedly reached a settlement agreement with attorneys representing 75% of the claims initiated, in which they said they will provide $8.8 billion to $9.6 billion to resolve the litigation.26
However, more than 20,000 additional cases have not agreed to Bayer's settlement offer and intend to proceed through the court system.27
Is There a Way to Find Pure Honey?
Beekeepers are, unfortunately, at the mercy of their neighbors' glyphosate usage, as they can't control which plants their bees choose to visit. Some beekeepers, however, are carefully managing where they put their hives to minimize pesticide exposure and keep track of when spraying occurs to help reduce exposures.28
This is an issue not only for honey purity but also for bee health, as glyphosate is known to harm bees. Even organic honey can be contaminated with glyphosate, though there are some organizations that offer glyphosate-free certifications.
The Detox Project is among them. If you see their glyphosate-residue-free certification on Manuka honey, it means the product has no glyphosate residues down to government-recognized limits of detection (usually 0.01 parts per million), and lower levels than the default government Maximum Residue Limits in the European Union and Japan.29