There is much myth, misinformation, and mistrust around pesticides and organic teas all over the world. We want to demystify this for you and share a transparent overview of pesticide usage in Chinese tea, current general regulations in the international tea trade, and the myth around whether one can taste pesticides in tea.
The concept of Organic Certification for Chinese tea also has some misconceptions when we're talking about historic terroir and protected tea regions. Having an Organic Certification doesn't automatically mean that tea is better than conventionally produced tea. The concept of Certifying for organic practices is relatively new to heritage farmers. While there is increasing awareness about this concept, overall there aren’t many incentives for them to get officially certified. The connoisseurs who focus on teas from top terroir are used to using taste as a benchmark. Excessive and in some cases any usage of pesticides or fertilizer will affect the taste of the tea, and that alone keeps the farmers in these regions at a very high level of accountability. The farther away from the top terroir quality you go, the more necessary having an Organic Certification would be to a farmer to prove the quality and safety of the tea.
We must establish the difference between top terroir heritage tea regions and large-scale commodity product farming to start this conversation. The practices and care taken at each level vary widely, with heritage tea regions taking a far more holistic approach to agriculture than plantations.
We work exclusively with heritage tea farmers from the most prestigious top terroir in China at Tea Drunk. They do not use anything synthetic in their processing because they will negatively affect the environment, the tea itself, and the livelihood of the farm families who live in the region. The use of chemicals is regionally forbidden in these top terroir regions because of the land protections and history. There are forestry policies set by the local government that ban the use of chemicals across the board, not just for tea. So, there are no synthetic pesticides used on the tea, and there are none anywhere nearby.
Most top terroir tea regions in China do not use any fertilizer because it could compromise the tea taste. If they do, and it is rare, they will use a natural version, such as plant cuttings or crushed tea seed shells. Excessive fertilizer use degrades the complexity of the final tea product. This compromise on the taste alone is a great discouragement for heritage tea farmers to use fertilizer. The most dangerous chemicals are found in herbicides, and those are definitely not used in top terroir. Below we break down some of the factors and practices involved in pesticides, organic growing, and regulations.
Pesticides
Like we mentioned in the intro above, the use of pesticides changes depending on the region. Farmers should use natural pesticides when necessary, but as you will learn, in higher quality regions, this is rarely necessary.
In lower grade plantation teas, pesticides are standard out of fear that the lack of usage will result in lower yield in both the short and long term due to threats of insects, pathogens, and weeds that get in the way of harvesting and competes with tea trees for resources. This practice is under the assumption that more is better than less for a commodity.
However, tea has a long history of being cultivated and appreciated in China before modern commoditization. Historic, top terroir teas are produced in regions with strict environmental laws. Natural pesticides can only be used when they are critically needed to protect the life of the trees. Most years, this is not necessary, and when it is it is a community and local government decision to do so.
The connoisseurship of the beverage demands quality over quantity and distinction over homogeneity. These foundations set a basis of an argument for the difference in needs and usage of pesticides in Chinese tea.
Understanding The Role Elevation and Climate Play
Pesticides are typically used during warmer months when problems with insects, weeds, and pathogens rise. High-quality teas are usually harvested early in the spring or come from cooler climates due to either elevation or latitude. The colder weather creates minimal to no risk of issues that would result in natural pesticides. The chances of a top terroir region with a cooler temperature having the need to use pesticides is very low.
Tracking The Harvesting Time and the Spraying Cycle
Depending on the tea style, many high-quality teas are harvested early in the Spring, and in the cases of many traditional teas, springs only. Tea Drunk teas are only harvested 10-15 days out of the year during the very early Spring harvest time.
Since pesticides are primarily used in the summer and fall, this puts the harvesting season of higher quality teas before the spraying season begins. This timing gives the tea trees a whole year to metabolize the pesticides if they are not washed away by rain first.
When commercial tea plantations harvest their summer and fall teas, they would have a much higher risk of pesticides as the harvesting would happen shortly after the spraying. In extreme cases where a combination of warm climate and monoculture rendered the tea trees completely reliant on pesticides, multiple sprays are needed throughout the year, thus increase the risk of residue.
Different styles of tea also have different reliance on pesticides. Top-quality green, yellow, white, and red teas demand tender picking of the tea buds and leaves available only in early spring. The highest quality of these teas is subject to a lesser risk of pesticide residue in general. However, Wu Long and black teas use more mature leaves that automatically push the harvesting window into warmer months, even for the best of them all. This inherent difference in the picking style of tea put even high-quality Wu Long and black teas at higher chances of needing pesticides.
Biodiversity vs. Monoculture
Evergreen tea trees are hardy, self-sustaining plants in forests. They have persevered for thousands of years in cultivation without the assistance of pesticides. So when tea trees are planted with agrobiodiversity in mind, the need for pesticides is reduced. The population of insects that targets tea can be controlled with their natural predators in a healthy ecosystem, while fungus and other tea pathogens are inhibited with nature's balance.
Long surviving tea trees in China's historic tea mountains prove that we once had a sustainable cultivation method. However, monoculture is prevalent in today's industry. Modern-day consumers usually associate tea production with rows of tea plants in a neat formation, covering entire hills, sprawling endlessly. This practice is monoculture. Monoculture not only encourages the infestation of tea targeting insects and fungus, but the lack of other plants, including weeds, also leaves some pests with no better choice in the surrounding environment but to attack tea trees.
Monoculture also exhausts the soil without ways to replenish it through natural biodegradation. This cycle increases the need for fertilizer, which can invite more insects and pathogens that target tea.
Diversity Through Varietals
Before commoditization, heirloom tea trees were diverse varietals that carry various pest and disease resistance genes. On top of monoculture, modern tea plantations usually consist of one or a few varietals of tea tree, which make them extra vulnerable to certain kinds of pests and diseases, deepen the need for more targeted pesticides. This practice can lead to resistance to certain pesticides and put the tea at higher risk of pesticide residues.
Residue and Regulations
A pesticide does not automatically mean poison to humans. The dosage has to be considered, and that's why tea safety has to occur within the residues framework. The amount of pesticide residues is laid out in maximum residue levels (MRL) based on the pesticides' harmfulness to humans. (We'd like to note: pesticide residue in the environment is a concern for many but is not in the scope of this article nor regulated with the MRL we are discussing.)
Usage of forbidden pesticides and overuse of allowed pesticides are common reasons why a produced tea could exceed the MRL. Sometimes pesticides evaporate into the air or get washed into the soil by rain. In potent pesticides with high persistency, residues can be found in the ground, then, in turn, get into the tea plant many years after the last application.
MRL and Trade Regulations
There is currently no global consent on the MRL in tea. MRL remains a trade regulation by individual producing and importing counties and regions of tea. While China as a producing country of tea has MRL on 48 pesticides as of 2017 (GB 2763-2016, effective 2017), the EU, as one of China's primary markets for tea, currently has 485 pesticides on the MRL list for tea.
Though the utmost goal of MRL is for the safety of consumers, some scholars in producing and exporting countries like China and Sri Lanka think the different MRL also become a measure of trade barriers. Each country has unique pest and pathogen problems, so the solutions are different, resulting in different pesticides. Imposing lower MRL on pesticides mainly used in one country but not the other creates a barrier that discourages tea trading with certain countries. For example, Dicofol is banned from being used in China on tea and has an MRL of 0.2mg/kg. But EU allows a higher MRL (looser requirement) of 20mg/kg. However, while China has an MRL of 15mg/kg for cyhalothrin, the EU sets it at a strict 1mg/kg. Japan, where cyhalothrin is uncommon, considers the pesticide an unregistered pesticide and therefore applies the general tolerance at a low level of 0.1mg/kg.
Green Peace vs. Tea Industry
In 2012, Green Peace Asia published a report on pesticide residues in name brand Chinese teas that caused a heated controversy in the industry. The report tested 18 teas from 9 well-known tea companies in China and announced that pesticide residue is prevalent in Chinese tea. Amplified by media attention focusing specifically on one kind of tea, Tie Guan Yin, brought the rapid decline of the tea. However, it's questionable whether the Richun brand's Tie Guan Yin even actually comes from the hailed terroir of Tie Guan Yin – An Xi – that was devastated consequently.
People from the tea industry and academia have come forward to rebuttal the claims in the report. Three of the main points are: residue does not equal poison (though the information did use EU MRL as reference); MRL is based on ground tea leaves while we consume tea in the form of brewing which results in lower risk of pesticides as many are not water-soluble; the teas sampled are mass-produced teas that do not represent actual premium teas from traditional terroir with artisanal processing.
Green Peace China did a follow-up report again in 2016 where 26 teas from 15 brands were tested, including six environmental-friendly teas from 3 brands. The report concludes that pesticide residues persist in some teas, but the environmental-friendly tea reported zero pesticides.
Unlike the 2012 report, the 2016 report was published in Chinese with a less critical tone. But it still caused another round of media war centering on the issue of pesticide residues in tea.
Many worry about the report's generalization of pesticide usage in teas being unfair for high-quality teas from colder terroir with traditional practices. The samples tested are all from very large companies with mass-produced tea. Green Peace's report lists specific brand names with no deliberated references to an accusation of all tea. Still, audience members who receive the breaking of pesticide news are unlikely to read the actual report and therefore possibly left with the general impression that most teas are unsafe to drink.
Can One Taste Pesticides?
Many modern-day tea connoisseurs claim that they can taste the pesticide residues in tea, providing an argument for zero to limited pesticide usage even just for the sake of maintaining untainted taste. We have also been curious if the unique numbing and stingy sensations we feel from drinking teas suspected with pesticides are from the residues. Unfortunately, after much research, the claim seems to be a myth though no conclusive experiments have been done to prove or disprove it.
The wine industry has been wondering the same. In a fascinating experiment done by French molecular biologist Gilles-Eric Séralini in 2017, 147 tasting tests were done by 71 wine professionals or chefs on 16 wines to find out if one can taste pesticides both with and without the distraction of other compounds in wine on the palate. During the tasting of pesticide-infused water, a shocking 85% of times, at least one pesticide was detected by smell alone. And 58% of the time, tasters identified all pesticides. However, out of the tasters who have successfully placed pesticides in water, only 57% could locate them again in wine.
While the experiment is groundbreaking in its daring attempt, criticism also ensued. One article by Prof. Andrew Kniss opened up his opinion on the dubious track record of Séralini, the morality of having people tasting pesticides as well as potential statistical errors.
We hope this article is informative for you and dispels some of the myths and misunderstandings around pesticide use and organic teas in China!
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