The situation of local fruit vendors has gone from bad to worse after the Thai Pesticide Alert Network (Thai-PAN) released its finding two weeks ago, revealing chemical contamination in popular Shine Muscat grapes.
Already struggling in a market excessively flooded with Shine Muscat grapes imported from China resulting in local supply-demand imbalance, vendors are now facing a significant price drop as consumers are alarmed at news of contaminated grapes. From prices ranging from 100 baht to several hundred per kilogramme at leading supermarkets, Shine Muscat grapes, popular for their sweet taste and soft texture, are now available at prices as low as 50 baht per kilo.
Despite the market reaction, Assoc Prof Chaniphun Butryee, head of the Master of Science Programme in Toxicology and Nutrition for Food Safety, the Institute of Nutrition at Mahidol University, urges consumers to not be overly worried because in reality, imported items are not what people eat every day.
"Shine Muscat grapes are mostly imported from other countries which is not what we eat every day, especially when compared to other kinds of grapes. Overreacting or not, people -- consumers and stakeholders alike -- should consider the recent finding as a wake-up call to be extra vigilant," said Chaniphun.
In collaboration with Chalard Sue (Smart Buyers) magazine under the Foundation for Consumers, Thai-PAN collected and tested 24 samples of Shine Muscat grapes from 15 locations around Bangkok and neighbouring provinces, including supermarkets, fruit stores and online fruit shops. The lab aimed to test for 419 agricultural chemicals in the samples.
Of the 24 samples, all were found to contain hazardous chemical residues, and 95.8% (23 out of 24 samples) contained chemical residues above the maximum residue limit (MRL) as stipulated by the Ministry of Public Health. A total of 50 chemicals were detected from all samples.
Furthermore, each of the tested samples were found to contain between seven and 18 types of chemical residue while 23 samples were found to contain between one and five types of chemical residue above the maximum residue limit.
The editor of Chalard Sue magazine, Tassanee Naen-udorn, said the test conducted on Shine Muscat grapes stemmed from public concerns to know if they are safe to eat.
"Chalard Sue received questions and suggestions from consumers that Shine Muscat grapes are currently available with enticing deals and promotions such as a huge discount or a buy-one-get-one-free promotion. Also they are available almost everywhere -- from big retail stores, leading supermarkets, convenience stores, mobile fruit stores, vendors to even online shops. Consumers are worried if the fruits contain chemical residues. The magazine joined hands with Thai-PAN to conduct a laboratory test on these grapes to find pesticide residues," she said.
According to figures from the Food and Drug Administration (FDA), this year Thailand has imported around 275 tonnes of Shine Muscat grapes, worth approximately 72 million baht. The FDA also screened these imported grapes and found that four samples were below its standard in terms of chemical contamination. Legal action has already been taken.
In terms of food safety, Chaniphun said that grapes are actually considered in the "risk group" when it comes to chemical contamination given they are more prone to pests and insects compared to other common fruits. When the news broke, certain public and private parties came out and suggested consumers calm down, saying the grapes are still edible while recommending fruit-washing techniques.
But speaking from a toxicological perspective, Chaniphun said it is essential that consumers have the right understanding of pesticides and insecticides so that they can take the right action for their own health and safety.
According to the expert, pesticides can mainly be categorised as systemic and non-systemic. Systemic pesticides are those absorbed by and transported through plants which mean they stay inside the meat of fruits and vegetables once absorbed. On the other hand, non-systemic pesticides are not absorbed and thus remain on the plant's surface. Only the latter can be washed away with water -- yet only to a certain extent.
Of the 50 types of chemicals found in the tested Shine Muscat grapes, 37 (or 74%), were positive for systemic pesticides which means they cannot be washed away with running water as suggested by some.
"This is all about communication," she added. "State agencies cannot just tell consumers that grapes are contaminated and should be washed before eating. They should not give general guidelines. When it comes to chemical contamination in fruits and vegetables, communication must be clear and accurate. They must give details about chemicals we are talking about and if they are systemic or non-systemic ones so that consumers can take the right action."
"Without clear and accurate information, it is like letting consumers rely on themselves," Chaniphun added.
Following the recent finding, Thai-PAN listed some short-term and long-term recommendations both for private sectors, the Ministry of Public Health and the government to curb chemical contamination in fruits and vegetables.
For short-term protocols, Thai-PAN recommends modern trade outlets and distributors selling the problematic Shine Muscat grapes take responsibility by removing the remaining grapes from shelves. Afterwards, strict measures should be implemented with suppliers and farmers who misuse agricultural chemicals which leads to contamination. For example, business operators should no longer import any produce from suppliers or manufacturers who keep breaching the rules. Importers, modern trade outlets and distributors should identify the country of origin so that back-tracing is possible.
For long-term recommendations, Thai-PAN encourages the Ministry of Public Health to create a Rapid Alert System so that test results and other related data can be distributed quickly and measures taken through the supply chain including the country of origin, importers, suppliers and distributors. Although the Thai-PAN suggests the Rapid Alert System be implemented by 2028, a new measure to ensure more than 95% of fruits and vegetables sold in Thailand are free from chemical contamination is expected to be in place by 2030.
In 2025, the FDA also plans to implement an active protocol against chemical contamination in fruits and vegetables including the Hold, Test and Release as well as the 1daan/1lab/1day measures where up to 2,200 samples of imported produce in the high-risk group are to be collected and tested after which results will be released within 24 hours. Business operators will not be allowed to sell fruits and vegetables that do not pass the test.
In the meantime, Chaniphun stressed that consumers should not be overly concerned about the chemical contamination of Shine Muscat grapes. When it comes to food, there are always two sides of a coin.
"Take fruits and vegetables, for example," she said. "Many times we hear that they are contaminated with chemical residues. But the World Health Organization still recommends the consumption of at least 400g of fruits and vegetables per day to cut the risk of cancer and coronary artery diseases."
These days chemical substances are all around, Chaniphun noted. For her, moderation is key to everything.
"Look at moo ping [grilled pork skewers] available at almost every corner of most streets. People eat them on a daily basis despite the fact that grilled meat is proven to contain hydrocarbons which are carcinogenic. We consume chemical substances every day. But we are still alive because a healthy body has a natural mechanism to get rid of chemicals. The same goes with fruits and vegetables. Instead of overreacting, it is more important to eat wisely. Instead of eating the same thing every single day, it is paramount to opt for a wide variety of foods," Chaniphun said.
"Also when it comes to chemical contamination in food, there is no one-size-fits-all solutions. Consumers need accurate information so that they can make the right choice and do the right thing."
