Q&A

During our investigation we have found that some vegetables contain excessive residues of pesticides the use of which is banned by the government. Actually all pesticides are toxic, with negative impact on human health and ecological environment. Generally speaking, there are two kinds of harm to human health: acute poisoning and chronic poisoning.

Acute poisoning refers to the immediate effect if the pesticide is swallowed, inhaled or absorbed through skin it occurs during exposure or shortly afterwards. The symptoms of poisoning include headache, nausea, excessive perspiration, air hunger, spasm, unconsciousness. The symptoms of pesticide poisoning can easily be confused with common illnesses and may go unnoticed. Acute poisoning can result in death especially without timely emergency treatment. Ingestion of excessive amount of Methamidophos is frequently fatal.

As well as the acute, short term adverse effects of pesticide, there is the risk of longer term chronic effects. Pesticide can cause a variety of chronic illnesses and conditions including cancer, reproductive disorders such as infertility (linked to low sperm counts) or genetic defects; and disruption to hormone, or endocrine systems which may take years to become manifested. Long-term intake of pesticide-contaminated  food might further result in a continuous accumulation of pesticide within the body. Chronic poisoning has no obvious symptoms in the body, and thus is hard to detect.

Over 170 kinds of pesticide have been ranked as carcinogen. Some pesticides such as DDT, Lindane, Atrazin are now suspected of being endocrine disrupting chemicals (EDCs). These chemicals affect parts of the body’s hormone systems at very low doses and can lead to increase birth defects, sexual abnormalities, reproductive failure and the risk of breast and testicular cancers, in animals, including humans. The mechanism of the effect is not well understood. Illegal pesticides found in this investigation, such as DDT, lindane etc., are very difficult to degrade and were banned by the government as early as 1983. Lindane,  has been banned in China and other 51 countries. DDT can get accumulated through the food chain,  and even pass through breast milk to the infant, its half life as long as 7 to 8 years. Other pesticides detected in the samples,  include highly and extremely hazardous  pesticides methamidophos, parathion and carbofuran. These pesticides, are all forbidden to be used on fruit and vegetable. Highly or extremely hazardous pesticide means that the intake through consumption or the skin of small doses of these pesticides can already be fatal.

Besides, mixture of different pesticides might bring on the cocktail effect, the damage to human body more severe than any single kind of chemical. However, we know little about the health implications of the combined “cocktail” effect of this exposure.  For example, research showed that a combination of chlorpyrifos and pyrethrum led to synergistic neurotoxicity. 

In our investigation, we have 32 samples among the 85 samples with more than 3 kinds of pesticide, including those illegal. If customers eat this kind of fruit and vegetable for a long time, their health no doubt will be greatly endangered.

2. What standards are adopted by Greenpeace to determine the excess of pesticide remnant? What is illegal pesticide?

To determine illegal pesticides and excessive residues of pesticide, Greenpeace takes the following official references into account: Maximum residue limits for pesticide in food by the Ministry of Health and the Standardization Administration of China, as well as the List of Banned Pesticides from the Ministry of Agriculture.

Illegal pesticide refers to pesticides the agricultural use of which have been banned by Ministry of Agriculture (MA), mainly including a dozen of persistent organochlorine pesticides such as HCH, DDT, tetramine and etc. Besides, according to the features of high toxicity and half life, 19 kinds of organophosphate pesticide are formally forbidden to be used on fruit and vegetable, such as methamidophos, parathion, phorate, sulfotep, carbofuran etc.

3. How do you carry out sampling? Why just about supermarkets? Why don’t you take samples from free markets of agricultural products?

From last November to this April, Greenpeace have carried out 5 samplings in different supermarkets of Guangzhou and gathered 85 vegetables and fruit samples, including Chinese leaf vegetables, beans, etc.

In this first pesticide residue investigation that we conducted, we choose supermarkets (including Parknshop, Vanguard and Carrefour) because they have got plentiful experience and capacity to ensure food safety, in mainland and Hong Kong, and huge client groups. Greenpeace believes that they have more responsibility to ensure food safety for their customers.

4. How many times has Greenpeace done the detection? By what institution? In what method?

From last November to April, Greenpeace have carried out 5 samplings in different supermarkets of Guangzhou and gathered 85 vegetable and fruit samples. Greenpeace activists bought these samples in different supermarkets, wrapped them up in plastic bags, and directly took them to the lab on the same day.

Greenpeace entrusted Eurofins Dr. Specht Laboratorien, a German company of international authority, to do the analyses. It carried out qualitative and quantitative analyses through the method of Gas Chromatography and Mass Spectrometry (GCMS), which is able to detect more than 300 different types of pesticide, including those of organic phosphor, organic chlorine and carbamate.

5. How about the degree of authority of the institution performing the analysis? Why didn’t Greenpeace choose an institution without the accreditation from Chinese government?

Eurofins Dr. Specht Laboratorien, which was responsible for analyzing the vegetable and food samples, is a globally leading institution in the field of pesticide detection for food and agricultural products.

Eurofin was chosen by Greenpeace to conduct this investigation because of its low pesticide level detection limit and capacity to conduct test for wide range of pesticides that has been banned globally.  Banned pesticide is our major objective for this investigation.

Since 1990 this company has been carrying out pesticide residue analysis according to Good Laboratory Practice (GLP), under the accreditation of EU. Their detection method has gained the EU certification of DIN ISO/IEC17025. Among their costumers for pesticide residues analysis are globally leading infant food producers. They developed the pesticide detection method of DFG S 19, which was adopted as an official detection method by CEN. The analytic results of Dr. Specht Laboratorien are of scientific accuracy. （www.eurofins.com）

6. Some supermarket has established Quick Detection System as their analytic method.  Why is there still a problem of excessive residues of pesticide?

Quick detection method is generally suggested as a way of elementary spot test, because it is of high pertinence and only effective for pesticides of organic phosphor and carbamate. This method has the following shortages:

First, there might be mistakes in the detection of pesticide residues. Some 14 different vegetables including garlic, shallot, caraway, leek, are likely to result in “false positive” because they interfere the test. Pigment might also affect the accuracy of detection results.

Second, it cannot analyze organochlorine pesticides, the use of many of which is banned by the government. To judge whether a sample meets the safety standards, apart from measuring the amount of residues, it is necessary to find out whether it contains illegal pesticides.  Quick detection method only allows the detection of the total amount of organophosphate and carbamate pesticides. Even if the amount of pesticide residues detected by this method is below the standard level, the sample may still contain illegal pesticides. Third, some kinds of pesticide cannot be detected.  Quick detection method is exclusively for organophosphate and carbamate, so it is unable to detect the following pesticides: endosulfan, benzethazet, fenproparthrin, ethofenprox, bisultap, hexythiazox, spinosad, etc.

In our investigation, we have found illegal pesticides of organochlorine and excessive residues of other banned pesticides in quite a few samples. Therefore, we think that the supermarkets have not established efficient detection measures in mainland.

7. Can we get rid of the excessive residues of pesticide in vegetables through cleaning and heating?

No. Consumers cannot determine the amount of pesticide residues from the appearance. Careful cleaning before eating can hopefully get rid of much of it. But some pesticides can be absorbed into the plant, so washing the exterior cannot completely get rid of all the pesticide. Heating is also unable to get rid of all the pesticides.

8. What is the difference between organic vegetable and pollution-free vegetable?

Organic vegetable is produced according to National Standards of Organic Product, without any chemical pesticide, man-made fertilizer, or any GE material. Therefore, organic vegetable has more strict demands on the planting condition, and is of greater safety. The production and processing of pollution-free products are based on Regulations on Pollution-free Products, which allows the limited use of restricted man-made chemical materials.

9. GE crops can help reduce the use of pesticide, so why Greenpeace doesn’t support the use of GE crops?

There are many efficient and proven ways to reduce or even eliminate pesticide, organic farming produces high quality food without pesticides. Many GE crops actually lead to increased or continuous use of pesticides. For examples the use of pesticides on GE herbicide tolerant crops such as soya in the US increased since the introduction of GE soya, farmers in the North of China still use high amount of pesticide on the GE cotton. GE crops themselves pose many unknown risks to both the health and the environment and as it involves living organisms they may multiply and spread, and negative effect is likely to be irreversible. Ge crops also threaten organic agriculture through contamination.

There are more favourable sustainable agriculture methods to eliminate or at least reduce pesticide use.

10. Why is it that there is also pesticide residues in organic vegetable?

Organic agriculture doesn’t use synthetic pesticide. But pesticides may be carried by wind from other farm fields using pesticides, or rain and soil may contain pesticides and may expose organic vegetables. Many comparison studies have shown that organic vegetable in many cases don’t contain pesticide residues, or in the rare cases that they contain residues the levels are small. In 2003 a study of BNN found that only 0.8% organic vegetable contains the excessive residues of pesticide, while the same percentage of ordinary vegetable is 8.4%. Besides, according to an American study in 2003, children eating ordinary vegetable have much higher level of pesticide in their urine than those eating organic vegetable.

11. How does the Chinese government control pesticide residues in vegetable?

Ministry of Agriculture (MOA) is responsible to guard the market against illegal pesticides.  The State Administration of Quality Supervision and Quarantine and departments of public health are responsible for the detection of pesticide residues in the market. Yet pollution-free and green vegetables under the special project of “vegetable basket” are in the charge of MOA.

China has established the National Pesticide Regulations since 1997 to regulate pesticide production, use and trade.  The implementation authority includes the Ministry of Agriculture, State Administration for Industry & Commerce and the Administration of Quality Supervision, Inspection and Quarantine.