Pesticides in Tea: Getting a Clear Picture Not a Vague Impression

Does your tea contain pesticides?
How much should that matter?

Tea worker applying pesticide

Many tea drinkers have an impression that it is at least slightly unsafe as a drink. The more they are concerned with tea as a wellness aid – green tea health benefits, non-caffeinated herbal teas, natural ingredients, and organic growing, the stronger that impression is likely to be.

The dominant concern is pesticides. How dangerous are they and how can you be sure they do not leave residues in the tea you drink? In most instances, you won’t be able to answer this question: “I get the impression that…. But I really don’t know.”

The aim of this post is to help you get a clearer focus on facts rather than impressions.

Tea Safety: 1) No problem, 2) Easy to avoid, 3) Worrisome, 4) Real bad

There are four positions a tea lover can reasonably take on this complex question of tea safety.
No one of them is self-evidently correct and, ironically, scientific data is often used to “prove” any of them.

  1. The problem is occasional and scattered. Tea is at least as safe as other imported farm produce. The occasional headline scares are just that. Tea buyers can ignore the issue. (Of the 420 food 2017 product recalls, voluntary withdrawals and safety alerts issued by the FDA,  non contained Camellia sinensis and just one was a sorta “tea” – a herbal concoction containing deer antler powder. Since 2013, there have been around ten precautionary recalls for salmonella risk, all in organic herbal teas and all from non-tea ingredients, such as ginger.)
  2. It is prevalent among no-name cheap teas. There are just too many media and some scientific reports of teas containing pesticide residues plus lead from car emissions and chemicals from the burning of coal as well as air pollutants that mark India and China, two of the largest tea growers.
  3. It is under-reported in its scope and the impact is commonplace. The major brands downplay the extent and degree of legal controls being bypassed. Teas that do not meet import requirements are widespread, not occasional. Study after study names brands, lists test lab findings and presents precise data.
  4. Tea is basically pesticide-laden. It is a very serious problem that is growing and poses substantial risks to both tea workers and drinkers. This is one instance of the threat to the food chain that makes pesticides and corner-cutting in quality control an escalating response to biodegradation, climate change and the intense economic pressure of global overcapacity and falling prices. Reports by leading think tanks, international policy, industry and research groups question if the many efforts to nurture sustainable production can turn the trends.

Some truths — or striking impressions

It’s very easy to fall into one of these positions just from impressions left by media reports, industry, political, and consumer groups, surveys, and headline scares. Some of these sources are strongly and openly committed to a social/political agenda. Others are much more tentative in their conclusions. Regardless, they rely on assumptions, definitions, and even folk wisdom that very often just leaves an impression rather than a sure understanding. You naturally take them on face value and respond accordingly.

Here are a few instances:

What’s your own impression of these conclusions from two widely publicized Greenpeace  reports on pesticides in Chinese and Indian teas?


Of 49 Indian tea samples, 60% contained at least one pesticide above the safety limits set by the EU. For Chinese teas, the figure was 67%. All 18 samples contained residues of at least three pesticides.

Your reaction? “Get the word out – China’s tea is polluted with illegal pesticides.”

Or these headlines, which provide detailed figures from scientific test labs?

Most Popular Tea Bags Contain Illegal Amounts of Pesticides. Avoid These Brands At All Costs.”

“Many Name Tea Bags Contain Copious Amount of Deadly Pesticides.”

“Dangerously High Pesticides in Celestial Seasonings Teas.”

These articles seem pretty clear cut. They are packed with supporting data on Maximum Residue Levels (MRLs), the universal scientific metric for regulating and measuring pesticides in foods. The word “safe” and “legal” seem clear, too. “Copious, toxic, dangerous, deadly, illegal…”

It’s hard not to accept that there is a serious pesticide problem.

That’s the impression. But, probe a little and look for what the words and measures actually mean and there is a strong case for reaching the conclusion that the teas are pretty safe, that China has greatly improved its handling of pesticides and that Celestial Seasoning’s teas are very safe.

One more impression. Organic teas do not use pesticides and are entirely safe. But they do use them. Really. They are not always safe and organic certification does not address lead and contamination from coal burning. Many of the very best teas that adopt biomanagement methods and are as pesticide-free as is possible are not organic. Even though they are (just not certified). Some mass farms that can afford the expensive certification grow mediocre tea in poor locations and with degraded soil and biodiversity.

Finally, MRL compliance data for, say, China or Vietnam teas are reliable measures of the pesticide residues you will ingest when drinking any of them. Not at all. Some of those teas are indeed toxic and dangerous and their damage to health known and substantial.

It won’t have any impact on you. The teas won’t ever get to you. Food safety and import controls have tightened substantially and exporters can’t dump pesticide-laden tea on the EU, Japan, Canada, US, etc. The evidence for this is solid: Just one tea in the more than 400 FDA food recalls and alerts. A 2013 EU report shows that tea, coffee, and herbal teas together had less than half the non-compliance rate of legume vegetables, amounting to 5.1% of the total. Actions include administrative sanctions, notifications, market withdrawal, and bans.

The aim in this Tea Journey post is not to evaluate or endorse a position along the no problem-giant problem spectrum. The issues are very complex and multi-dimensional. In many instances, your view is based on feeling, instinct, caution, skepticism about science, business, and vested interests. This is fully reasonable. It’s your body and health. Much of how you choose to factor safety into your decision is a matter of trust and preference, not “science” or “fact.”

The purpose is to alert you to the facts behind the impressions, so that it is your own assessments rather than someone else’s powers of persuasion that shape your conclusions and trust – and hence your tea buying and choices.

Measuring and permitting tea pesticide levels: MRLs

The core issue is captured in the Greenpeace reports and headlines. The impression is that “safe,” “legal,” and “limit” mean what you assume. Any given tea pesticide content can be classified in precise numbers that indicate the milligrams of detected residue per kilo (mg/kg) that it contains. The results can then be compared with the MRL – Maximum Residue Levels. If the test results indicate 15 mg/kg of residue compared to a published MRL of, say, 10, it means that the tea is unsafe, right?

Whatever thought passed your mind reading that sentence is probably incorrect.

MRLs are trade rules not direct safety measures. There is no one MRL. And there’s no systematic methodology for setting them. They are are pragmatic and situational, set by regulators and import authorities in individual nations and by the EU. They are rather like a highway speed limit. They really stand for “tolerance level.” They are very much a judgement call and almost every trade regime builds in a large safety factor. A trade commission from Indonesia provides a typical instance of over-restrictive MRLs. Its teas have been locked out of Japanese markets by an MRL of 0.2 where the medical evidence is that human tolerance is in the 2.0 range. Vietnam’s government points to reduced exports and declining prices from being unfairly “locked out” by the EU and Japan. China labels MRLs arbitrarily imposed non-tariff barriers to trade.

Japan is among the strictest regimes and China used to be one of the most lax but has tightened its tolerance levels very substantially. Kenya, Korea  and Sri Lanka recognize that the best response to MRLs is to improve quality.

Due to the non-harmonization of MRLs in tea, tea producing and exporting nations cannot count on a single set of standards for the industry. Each market may hew to a different set of MRLs, making it costly, if not impossible, to conform to global markets.

Differences in MRLs and hence in “safe”, “toxic”, etc.

The Greenpeace study uses EU MRLs. Those are often very different from those set by Japan, the US, Canada or Australia. This table from the FAO shows just the range of MRLs for China, the EU and Japan for just a small subset of the close to 500 pesticides for which the EU has set MRLs and Japan 800 or so.

To take just one instance from the Greenpeace China report, one of the top global brand’s green teas tested out at 0.13 mg/kg. The EU MRL at the time was .01 indicating this tea is not safe. But it is safe in the US, where the MRL is 50 and also in Japan, which has the tightest restrictions on harmful pesticides. There, the MRL is 30.

The EU figure is not quite appropriate yet this tea would not get through customs.

Dicofol is a commonly used tea pesticide. China has very tight limits specified as part of its program to improve China’s export position and prices: 0.2, which corresponds to “traces” while the EU allows up to 20 and Japan just 3 mg/kg. Sweden suspended its use for many years. The UK limits the number of applications per annum for individual crops.

It’s structurally similar to the infamous DDT, whose destructive global impact, especially on birds’ shells still stands as the emblematic warning of pesticide dangers. It’s a nerve poison. The World Health Organization classifies as a Class II “moderately hazardous” pesticide. There is a growing effort to “harmonize” MRLs, with many organizations and acronyms involved: FAO, CODEX, WHO, and many NGOs (non-Government Agencies).)

MRLs are a trade measure. Obviously, they very much take safety into account but they also include trade encouragement or deterrence.

One limitation of MRL figures is that they measure the residue in the trade form of the tea: the dried leaf. This does not directly translate to the level in the infused form: the tea you drink from your cup. Many pesticides are insoluble and do not leech into the water. This is commonsense. Tea growing depends on rain patterns. Pesticides that get washed off will simply drain into the soil.

A noted example of a scare headline on tea contamination that to say the least is less than meets the eye and mind comes from Japan. After the nuclear power plant meltdown in 2011, levels of cesium radiation in tea leaves soared. Sales and exports plummeted.

Impressions can be hard to shift. Farmers stressed that government regulations measure the concentration in the dried leaf – the trade form. They do not measure the final product, the drink that is an infusion of water and tea. Using established medical data, they pointed out that you would have to drink two hundred bottles of green tea daily for a year before there would be any health risk. “When people are fearful, they are not going to buy your product, no matter how many times you tell them they are safe.”

Bigelow has recently been sued by the Organic Consumers Association for levels of the controversial pesticide glyphosate that exceed the US MRL of 1 part per million (a restatement of kg/mg but the same measure.) Bigelow challenges the accuracy of the tests and points to a lab test of the same teas that came up with a figure of 0.38 ppm. It also points out that the MRL for carrots is 5 ppm, barley 30 and some grains 100.

“Organic” means…. What, exactly?

A powerful impressionistic term is “organic.” It is the solution to the entire issue of pesticides. Just buy only organic teas. Surely, that’s obvious.

The first reason to choose them is they don’t use any pesticides. Well, they do. But these are derived from natural sources not synthetic ones. There are around 20 chemical insecticides, fungicides and herbicides approved by the US Organic Standards. They are natural. They are not always safe. Rotenone, for example, was widely used for many decades. Research began to show that it killed off mitochondria in living cells and increased risks of Parkinson’s Disease.

Back to impressions.

Here’s the case against organic as universal solution. First, it is a certification not a description. To use the term, particularly in China, growers must pay large fees for inspection, consultation, investment in record keeping systems, tests, etc. There are many reports of corruption, of mass commercial farms exploiting their size to get rights to the valued marketing advantage but as one commentator notes, these farms are organic by the letter not the spirit – factory farming is factory farming. Organic farms may not use synthetic pesticides but a Consumer Reports Study of a range of organic foods found that 25% of them contained traces of 300 non-organic pesticides. These often come from neighboring farms, water run-off, pollution and poor soil management. Finally, organics have higher levels of pathogens, spread by fecal contamination from natural manure.

Beyond impressions: The emerging clear picture

So, if the language and measures of impression need careful evaluation and don’t offer reliable and exact good/bad, safe/toxic distinctions, what is the alternative basis that tea lovers should add to their perspective?

Here’s the one that you’ll find dominant among tea providers, policy makers, experts and tea lovers:

  • “Pesticide” does not automatically mean bad or organic translate to good. Good and bad are outcomes of the broader biodynamic management process and ethos.
  • “Pesticide-free” is a meaningless concept. Volume production of cheap foods is impossible without them. The subtropical climates in which tea grows are a breeding ground for some three hundred varieties of voracious pests. Without controls, the crop loss from a harvest will be in the 10-40% range. Even where pesticides are not used, it is highly likely that residues will still be found in the tea. The diagram below captures this.

  • The core issue is “terroir.” This is the combination of location, soil, climate patterns, biodiversity, elevation, culture and biomanagement methods. It’s a term borrowed from wines. There are relatively few regions on the planet where all these factors come together to grow tea naturally – as part of nature, where nature does the heavy duty work.  The best terroirs are the mountain  regions that are noted for their pedigree teas: Uji, Darjeeling, Wuyi, Alishan, Xishuangbana, Nuwara Eliya and others. They are less vulnerable to infestation and farmers have less incentive to use pesticides.
  • The emerging principle for managing food safety is simple: Be able at any step in the supply chain to trace the tea back to the farmer. The US Food Safety and Modernization Act, being phased in starting this spring, includes Foreign Supplier Verification Programs, Hazard Analysis, Risk Management, etc. The major consumer brands are tightening links and responsible relationships along the supply chain. They are providing incentives and support for sustainable development. The Greenpeace charges do not seem justified.

For you, the tea drinker, the extension to all this is know your supplier and learn about  their suppliers — the growers, their terroir and pedigree.

This blog post raises questions. Each of the areas it covers is a complete field in and of itself. The hope is that by freeing you from impressions, you will better able to choose your position and make the best choices for yourself.

9 thoughts on “Pesticides in Tea: Getting a Clear Picture Not a Vague Impression

  1. Note that this is a general response to the issues raised.

    Regarding the OOS (out of specification) examples reported in the “Pesticides in Tea: Getting a Clear Picture not a Vague Impression” article, this eloquently reports a big-picture example of identifying what appears to be major concerns in the global quality supply chain This information will hopefully bring more awareness to these product quality issues of concern; after all, we all want to consume safe and healthy food products.

    From my experience working with manufacturing botanical ingredient health products, an effective supplier qualification /certification program, including active monitoring, is required along with an aggressive quality control program that includes testing for pesticides, heavy metals, and other constituents of concern, at least on the incoming raw materials and finished products too. This is done for each lot/batch, no skipping. When a finished product is tested and is OOS for pesticides or heavy metals or some other specification, the quality management system has failed and swift corrective actions are required.

    OOS can be a symptom of one or more quality management related problems that may require one or many actions, including training, new and/or revised SOPs, new personnel, expert consultants, quality systems auditing and improvements, product testing method review and validation, and supplier re-qualification, for example. Also, an annual independent quality management audit with a scoring system for specific action item follow-up is beneficial as part of a quality management system.

    Failure of a quality management system is unacceptable with today’s incredible technology. Yes, suppliers occasionally ship to their manufacturing customers OOS ingredients, as the article exemplifies, but the quality control system of the finished product company needs to identify OOS ingredients and prevent using them in their products. This is the black and white perspective. However, the real-world perspective sometimes complicates things, which is another story, and can lead to causing OOS situations.

    Ideally, when a third party is testing finished products the product company should be contacted prior to testing for a few reasons, including: knowing about the established product specifications and testing methods; to immediately alert a product company if third party testing result indicates an OOS situation so the product company can conduct a prompt OOS investigation; and to have the opportunity to evaluate the third party testing methods/results, which could have issues and often do in my experience.

    Product companies with a good quality control program benefit tremendously and are rewarded with a high level of consumer safety and satisfaction.

    Daniel Gastelu, MS, MFS, President/Scientist
    Health Product Business Success LLC

    1. I appreciate the additional perspective. Question: if you drink tea, which tea(s) do you drink. I ask this, knowing that, speaking for myself, it is one thing to deliberately ingest anything when the possible effects are known, and quite another when one had not made the proper inquiries. “Tea.” Sounds so simple, relatively speaking. Thank you.

  2. Daniel – that’s an interesting perspective. However if tea producers tested each lot or batch for heavy metals and pesticides they would be out of business very quickly!

    The current approach is to establish robust preventive management systems to ensure that (legitimate) crop chemicals are used properly/sparingly, only when absolutely necessary, and the manufacturers’ instructions are followed to the letter. Non-chemical systems are helpful too of course.

    A QA (rather than QC) approach can then be taken if CC usage is properly under control.

  3. The big thing is that most agricultural situations are likely dynamic. Changing rainfall, spilled chemicals, workers who don’t follow procedures for whatever reason and companies who have to make a profit no matter what. So if things change in the tea growing workstream, unknown to the people who have decided that things “should” be going well customers will get OOS tea leaves. So tea growers are taking a chance on customers health sort of without warning them that the tea could hurt them under some situations. Hard to tell, harder to prove. The fact that a scientist will vouch for the process is nice, but there appear to be lots of opportunities for errors. Not to mention that the quest for maximun profits makes little problems easy to overlook.

  4. I have been gifted with three containers of supposedly premium teas which originated in China. Before I use or discard these products, where can I get these products tested in Canada?

    1. EMSL will do a fine job testing these teas for your Julie.
      If the tins are sealed, safety can be easily verified by reviewing labeling as all China tea exports must comply with stringent testing requirements. You can also visit the brand’s website for verification via third party inspectors.

  5. Since the country origin of the purchase of these gifts cannot be verified but it is likely China, no information is printed in English but the label bears a number on each of the tea products. Would that information be helpful in tracking the safety of the product?

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