Overview of Pesticide Residue in Tea and the Call for Harmonized MRLs
Jun 16 2003
Only a small number of the 320 pesticides which can no longer be used in the EU after next month concern Indian tea growers. And the regulation in question does not apply to producers outside Europe, of course, unless they export to the EU. Even so, they have until January 1, 2005 to meet the EU requirements.
The efforts by the EU authorities to meet public concerns are reflected in the way in which they set MRLs. These can be set at levels which are unnecessarily low, in which case they can be regarded as a non-tariff barrier. The Codex Alimentarius, a joint FAO-WHO agency which develops food safety standards, sets them at what may be regarded as the upper limit from the viewpoint of public health, in order not to hamper trade. The EU authorities set them at a level between these two limits.
COMMITTEE ON COMMODITY PROBLEMS
INTERGOVERNMENTAL GROUP ON TEA SIXTHTEENTH SESSION
1. At its last session, the Intergovernmental Group (IGG) on Tea recognized that there was a lack of global harmonization in fixing the maximum residue levels (MRLs) on tea which could constitute a barrier to trade and impose significant costs of compliance on tea exporters. Therefore, the Group decided that further actions were required in addressing the issue, including the collection of more data on MRLs for all commonly used plant protection products based on Good Agricultural Practices (GAP) and Hazard Analysis and Critical Control Point (HACCP) principles by tea producing countries.
Many of China’s most famous regions, Like the West Lake area in Hanzhou which produces the most prized Dragon Well (Long Jing) is almost entirely out of bounds for any company based in the Europe. The tea made in these areas destined for the most wealthy section of China’s population. As it is not intended for export, the extra steps to ensure that pesticides and fertiliser meets EU standards are not in place.
We send our teas for testing in Germany as there is not currently a laboratory based in the UK that regularly tests teas.
I have had the most trouble in finding EU compliant teas in Taiwan.
Many of our teas come back with no pesticide residues found – this happened this year with our Anji Bai Cha.
Link to Summary of Greenpeace China (2012) and India (2014) Reports.
I have dedicated an individual article to these reports because they have received a lot of attention.
October 19, 2012
Nigel Melican of TEACRAFT offers the main substance of the article,
(i) Pesticides traces are universal in food – no tea in the world can have absolutely totally zero pesticides – nor can or does an organic apple or carrot. Consequently Maximum Residue Levels (MRLs) are set by importing countries. Presence of a chemical below the maximum safe level is accepted – but Greenpeace (through ignorance or ingenuousness) ignores this and rants against “drinking toxic pesticides in their tea” while naming and shaming some tea companies with well below MRL levels – no libel laws in China?
(ii) No reference is made in the lengthy Greenpeace China report to MRLs – particularly the EU MRLs which are internationally accepted. In fact, if you take the considerable trouble of comparing the Greenpeace data with EU pesticide limits for the 28 chemicals mentioned then 5 of the 18 teas accused actually fall below the MRL limits for all 28 and two more tea exceed by a trace level of 1 mg/kg on 2 chemicals. This leaves 11 teas non-compliant for one or more pesticides, were they to be sold in the EU.
(iii) These teas were purchased in the local Chinese market so Greenpeace China should have been comparing them with Chinese MRL legislation – they may very well be compliant with this (I do not have access to Chinese MRLs).
(iv) Nowhere in the report does Greenpeace China suggest that the non compliant teas are representative of China teas presented for Export – but commentators in the USA and UK have erroneously and immediately jumped to this conclusion.”
Austin Hodge adds,
It is also interesting that the two biggest culprits in the Greenpeace expose were not even Chinese companies, they included Lipton and Ten Fu/Ten Ren. Lipton is the leading brand in China, largely because there really aren’t any national Chinese brands, and Ten Fu which Americans know as Ten Ren is a Taiwanese company, and is probably the leading tea retailer in China.
We have committed that by 2020 all our food raw materials will be produced using sustainable crop practices, minimising the use of pesticides through integrated pest management techniques, and with due care for the environment and the health, safety and livelihood of farmers.
The Guidelines’ recommendations on the use of pesticides in the tea industry are aligned with the recommendations of international authoritative bodies, specifically:
-> The World Health Organization Recommended Classification of Pesticides by Hazard;
-> The Stockholm Convention on Persistent Organic Pollutants (POPs);
-> The Rotterdam Convention on Prior Informed Consent (PIC) for certain hazardous chemicals and pesticides in international trade.
Commitments and Ambition We will work with our suppliers and with the tea industry in general to eliminate the following pesticides from use in Unilever’s entire tea value chain by the end of 2014:
-> WHO Class 1a or Class 1b pesticides;
-> Pesticides listed as Persistent Organic Pollutants (POP) in the Annexes to the Stockholm Convention; and
-> Pesticides subject to the Rotterdam Convention on Prior Informed Consent (PIC) procedure for certain hazardous chemicals in international trade, as listed in Annex III to the Convention
Further, our ambition is the elimination of WHO Class II pesticides from tea production for Unilever by 2020.
In addition, we will work with our suppliers and national governments or regulatory agencies to eliminate or actively reduce as far as reasonably practicable the use of WHO Class III pesticides.
By 2020 at the latest, Unilever will only source tea which is traceable to sustainable sources.
List of Crop Protection Products Not Acceptable for Use in Tea Production
List of Crop Protection Products Subject to Requirements for Reduction of Use
Reasoned opinion on the modification of the existing MRLs for pyriproxyfen in stone fruits and tea. European Food Safety Authority
29 November 2013
The residue data on orange leaves, supported by data in cucumber leaves, were used to address the residue situation in tea leaves, as no metabolism study on leafy crop is available.
No data are also available on the transfer of residues from tea leaves to tea infusion.
EFSA concludes that the import tolerance of pyriproxyfen in tea, cherries, plums and peaches will not result in a consumer exposure exceeding the toxicological reference value and therefore is unlikely to pose a public health concern.
Marketplace: Full tea test results
March 7, 2014
After tests conducted by the Canadian Food Inspection Agency in 2009 and 2011 revealed levels of pesticide residue that exceed Health Canada’s allowable limits, Marketplace commissioned testing through an accredited lab to see if teas with these amounts of pesticide residue are still on the shelf. Here are the results.
Not much but data is offered, so I refer you to Tammy Catanina.
One of the chemicals found was Endosulfan. This chemical is one of the most toxic pesticides on the market today. It is responsible for many fatal pesticide poisoning incidents around the world. Endosulfan is also a xenoestrogen—a synthetic substance that imitates or enhances the effect of estrogens—and it can act as an endocrine disruptor, causing reproductive and developmental damage in both animals and humans.
The second chemical they found was Monocrotophos. It is acutely toxic to birds and humans. Being also a persistent organic pollutant, it has been banned in the U.S. and many other countries.
Food safety standards have different effects on consumption and trade flows. Primarily they aim to maintain consumer safety through defined sets of limits and regulations, but these regulations could have a trade deterring effect when exporters cannot comply with the standards. As one of the food safety standards, MRLs set maximum levels of pesticide residue that can be traced in food and food products to ensure food safety
In 2013 the European Food Safety Authority (EFSA) reported the results of its analysis of pesticide residues found in food in the European Union (EU) which was carried out in 2010. The foods that had MRLs exceeding the acceptable EU limits were legume vegetables, spices, nuts, table and wine grapes and leafy vegetables. The highest non-compliance rate was found in legume vegetables (11.1 percent),while the lowest rates were reported for eggs (0.2 percent). According to the report, 5.1 percent of the tea, coffee and herbal infusions sampled were above the accepted maximum residue limits.
In addition, food safety standards had a much larger effect on trade than import tariffs. Similarly, in 2012, Wei et al. found that MRL limits applied by importing countries significantly reduced tea exports from China.
Based on available data, observations on country-specific export trends indicated that some major exporters,such as China,experienced losses in exports to conventional tea markets, particularly the EU markets. The loss occurred especially after 2000,when the EU expanded the number of pesticides regulated, and in late 2008 when EU MRL regulations with low default values, particularly for older pesticides, came into effect.According to available information, although conventional tea exports to certain EU markets decreased over the years, organic tea exports seem to be performing well.
The attempt and acceptance of using the brewing factor in the establishment of MRLs in dry tea
Documents entitled “Assessment of MRLs for pesticide residues in tea” and “Assessment of MRLs for Pesticide in Tea” were adopted by CCPR and concluded in CCPR report in 2011 and 2012
Procedure for determination of Brew Factor
To determine the brew factor, the data on residues of a pesticide in both dry tea leaves and the residues in the tea brew prepared from the same dry tea leaves are required
Brew Factor = Residues in tea brew (mg/kg) ÷ Residues in dry tea leaves(mg/kg)
China is particularly vexed by what it terms administrative or “non-tariff” barriers to trade. There are glaring examples in which residue standards vary by three hundred to five hundred fold among trading nations despite the fact that the CODEX Alimentarius lists perfectly rational thresholds adopted globally.
There are currently 734 pesticides in use around the world. Japan tests for about 200 and lists 50,000 provisional MRLs in imported foods. The European Union lists more than 140. The United States, in contrast has a much shorter list. In addition to discrepancies on the lists there are standards legally adopted by countries wildly out of sync with the majority of trading partners. Delegates are seeking harmonization of standards.
One critical concern stems from a U.S. Environmental Protection Agency (EPA) decision in 2013 that allows a banned pesticide in tea imported from China until mid-2016. EPA’s decision to provide “additional time to transition to an alter-native” to the highly toxic organochlorine insecticide endosulfan puts consumers in harm’s way.
In the U.S., the Food and Drug Administration (FDA) consistently finds high levels of illegal residues on imported tea that eventually finds its way to the American consumer. This includes permethrin (a synthetic pyrethroid, linked to cancer and endocrine system disruption), DDE (a metabolite of DDT, banned in the U.S. in 1972), heptachlor epoxide (a derivative of the pesticide heptachlor, which was banned in the U.S. for use in agriculture and as a termiticide due to its carcinogenicity and persistence in the environment),4 and acetamiprid (a bee-toxic neonicotinoid).
An analysis of the most recently published FDA data on residue levels in tea (black, green, and oolong) from 2008 to 2012 reveals a high rate of violations. Out of the 65 samples of tea analyzed over these five years, nearly 30 percent had two or more illegal residues, with one sample from 2012 containing up to 14 violations. Of the 94 violations found in these samples, 76 were listed as “no registration” and 18 as “excess of tolerance.” Many of these violations are for pesticides that are currently used in U.S. agriculture, but lack a tolerance and presumably exposure data for use in tea, such as acetamiprid (a neonicotinoid), or permethrin (a pyrethroid). Other chemicals that were found to be in violation have been long banned from use in the U.S., including DDE (a DDT metabolite), carbendazim (MBC) (not allowed for use in agriculture), and heptachlor epoxide (a derivative of the pesticide heptachlor, which was banned in the U.S. for use in agriculture and home use due to its carcinogenicity and persistence in the environment).
The term “import tolerance” is used as a convenience to refer to a tolerance that exists in the U.S. for which there is no accompanying U.S. registration, but that meets U.S. food safety standards. According to the Global Maximum Residue Limits Database and the Code of Federal Regulations, tea leaves are shown to have 21 pesticide tolerances, of which 11 are import tolerances.
Although requesting an import tolerance requires data on product chemistry, residue chemistry, and toxicology so that EPA can assess potential dietary risk and make the required acceptable risk finding, the agency does not require data on worker exposure, residential exposure, or environmental fate and effects, which are required if the pesticide were registered for use in the U.S.
In 2010, EPA proposed to phase out all tolerances for endosulfan during the period 2012 to 2016 based on use, as it “can pose unacceptable neurological and reproductive risks to farmworkers and wildlife and can persist in the environment.” However, in 2013, EPA allowed residues of the cancer-causing insecticide endosulfan on imported Chinese teas until July 31, 2016, in order to provide “additional time to transition to an alternative to endosulfan” and raising serious concerns of further exposure to the toxic carcinogen for farmworkers and consumers. The agency proposed a transition time that would allow growers time to adopt alternatives, with the last four uses ending on July 31, 2016. For tea, EPA proposed an immediate revocation, since there is little, if any, endosulfan used in tea production in the U.S. However, the Chamber of Commerce of the Zhejiang International Tea Industry filed a complaint indicating that it would need five years or less to find feasible alternatives to endosulfan. It also indicated that it was unable to provide comment on the tolerance revocation ruling since EPA did not provide proper notice to the World Trade Organization. In acknowledging this oversight, EPA now allows endosulfan residues of 24 parts per million (ppm) in imported Chinese tea until July 31, 2016. Despite the risks posed by endosulfan residues, EPA sees the decision as “appropriate,” raising questions of whether EPA is putting economic interests ahead of public health.
According to reports from FDA’s Pesticide Monitoring Program (PMP), which analyzes and reports on pesticide residue levels in imported and domestic food, tea has been listed multiple times over the past five years as an import commodity that “may war-rant special attention,” a designation that is triggered for com-modities with (i) at least 20 samples analyzed or with a minimum of three violations, and (ii) a violation rate of 10 percent or higher.
Over these five years, tea appeared on this list in 2008 with a 23% violation rate, and again in 2011 with a 26.7% violation rate. In FDA’s most recent report for 2012, oolong tea was found to have a 100% violation rate, and an overall 50% violation rate for all tea samples analyzed. While the sample sizes in FDA’s analyses are small, they highlight a persistent problem regarding tea imports imported tea samples contain pesticide residue higher than established tolerances or for which no tolerance has been established, putting American consumers at risk.
The international bodies seeking harmonization of standards for pesticide residues are not working to ensure adequate protection of consumers and farmworkers. Standards, such as those in the European Union (EU), have allowable levels that are often lower than many countries, including the Codex Alimentarius (created by the Food and Agriculture Organization [FAO] and the World Health Organization of the United Nations to develop harmonized international food standards).
Other efforts to increase sustainability include standards developed by organizations including Fairtrade International, IFOAM Organic International (formerly International Federation of Organic Agriculture Move-ments), and Rainforest Alliance (see box), the Ethical Tea Partnership (ETP), and UTZ Certified, which together have certified or verified 12 percent of global tea production as of 2011/2012.
According to the International Institute for Sustainable Development, one-third of production is subject to voluntary sustainability standards on the international market (or 4% of global tea production and 9% of exports).
The European Union exercises official checks on tea to guarantee compliance with the European food safety standards. The most common issue is compliance with maximum residue levels (MRLs), especially regarding tea from China. Non-compliance cases are registered in the RASSF database. In the event of (repeated) non-compliance, tea from non-complying countries is registered and included in a list for increased levels of official checks.
However, individual buyers in Germany for example, may have stricter requirements on MRLs than the official limits as part of their private standard (such as 30% of the level of the European Union).
The residues that are most commonly found in tea are dicofol, ethion, quinalphos, hexaconazole, fenpropathrin, fenvalerate and propargite. Residues vary by country of origin, however, and are constantly changing.
In recent years, issues have emerged with regard to the maximum level of anthraquinone, which is set at 0.02mg/kg for food, including tea leaves. In many cases, anthraquinone has not even been used as a pesticide on tea plants. The tea becomes contaminated during drying or packaging, or by smoke caused by tea drying. The European industry is continuing its research to find out the root cause for anthraquinone contamination. If anthraquinone contamination is not the result of pesticide contamination, it might fall under the contaminant regulation in the future.
Link to summary of more recent FDA Pesticide Reports, including a year focused on tea.
25 July 2018
Some of the food products with MRL exceedance rates above the average are products, which were subject to increased import controls (e.g. tea, okra, basil, parsley, celery leaves) under Regulation (EC) No 669/2009.
Among food commodities for which at least 30 samples were analysed in 2016, the highest non‐compliance rates were reported for the following items: vine leaves from Turkey (41.9%), sweet peppers from Dominican Republic (12.6%) and from Egypt (10.5%), tea leaves from China (11.4%)
Notably, 589 samples contained 10 or more pesticides (71 samples of processed and 518 samples of unprocessed products, such as table grapes (81 samples), strawberries (58 samples), tea (56 samples), apples (32 samples), sweet peppers (32 samples), lettuces (26 samples) and pears (20 samples).
Contaminants with unclear origin in concentrations exceeding the legal limit (e.g. nicotine in cultivated and wild fungi and in tea, anthraquinone in tea, cardamom and wild fungi).
A high frequency of MRL exceedances for anthraquinone in tea was identified; the highest residues amounted to up to 0.37 mg/kg while the MRL is set at the LOQ of 0.02 mg/kg. Measures in tea producing countries are needed to fully investigate the causes and to implement best practices in tea production.
February 1, 2018
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.
2. It is prevalent among no-name cheap teas.
3. It is under-reported in its scope and the impact is commonplace.
4. Tea is basically pesticide-laden.
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.
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.
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.
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.
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.
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 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.
May 29, 2018
The Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) extraction method is commonly used for pesticide extraction, as it involves a single acetonitrile extraction and simultaneous salting out with magnesium sulfate.
The Intuvo 9000 GC and the 7000C triple quadrupole GC/MS system can confirm and quantitate pesticide residues at the low ppb level in loose-leaf black tea and organic honey extracts in keeping with EU MRL requirements.
Harmonization of MRLs in tea is recognized by the IGG on Tea as an issue requiring urgent attention to address concerns on residue levels in tea, their possible effects on consumption and to ensure that tea consumption continues to be safe.
26 February 2018
Italy proposed to raise the existing MRLs of propargite from the limit of quantification (LOQ) of 0.01 to 4 mg/kg in oranges and from the LOQ of 0.05 to 50 mg/kg in tea.
EFSA concluded that the use of propargite on oranges and tea as reported in the countries of origin will not result in a consumer exposure exceeding the toxicological reference values and therefore is unlikely to pose a consumer health risk. However, it should be noted that the risk assessment is affected by uncertainties linked to the toxicological profile and the reliability of results for some of the metabolites included in the residue definition...
Based on the residue trials, an MRL of 50 mg/kg for tea could be derived. However, a risk manager decision is required whether the setting of a MRL of 50 mg/kg for tea is acceptable since the MRL reported to be into force in India is 10 mg/kg. It is noticed that disregarding the highest value (statistically detected as outlier) a MRL of 10 mg/kg is derived from the remaining seven trials.
Low acute toxicity is observed when propargite is administered by the oral route. In short‐term oral studies with rats and dogs, the target organ was the jejunum in rats and the haematopoietic system in dogs. The dog was the most sensitive species. The relevant short‐term oral no observed adverse effect level (NOAEL) could not be identified as the lowest dose level tested in the 1‐year dog study was a lowest observed adverse effect level (LOAEL) (5 mg/kg body weight (bw) per day) (EFSA, 2011).
June 18, 2019
Zheng Guojian, director of China’s National Tea Quality Supervision and Inspection Center, told World Tea News that 7% of China’s tea acreage now meets all export requirements for organic tea imposed by Japan, the European Union and the U.S. National Organics Program.
Half of the county’s tea operations meet lesser requirements created to curb monoculture and ensure ecological practices. These teas are certified as “ecological tea.” There are also strict restrictions on the use of chemical pesticide and fertilizer in the ecological tier. “It is important to emphasize that this tier is readily compliant with purity standards in the EU, Japan, and other importing nations,” said Zheng.
In February 2015 China adopted a “zero-growth” action plan regulating fertilizer and pesticide use by 2020. The goal is to eliminate “excessive application of fertilizer and blind application, which brings about cost increase and environmental pollution. It is urgent to improve fertilization methods and improve fertilizer utilization.”
Production is reduced an average 19% when growers switch to organic practices which requires greater expanse of organic certified acreage.
April 22, 2019
Her analysis of tea found that of the 26 brands, nine contained “barely quantifiable” traces of residues but four showed “very inadequate” results: high levels that exceeded regulatory limits and/or a wide range of pesticides. One black tea is a definite surprise. It is produced by Damman Frères, one of the luxury tea names with an outstanding reputation for flavored and natural teas. It showed traces of 17 pesticides. Another brand contained four times the authorized limit of anthraquinone, a bird repellent. This was the most common chemical compound found, along with a fungicide, folpet. The article notes that all the teas contained metal traces, including cadmium, mercury and arsenic.
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 range of 10-40 percent.