Tag Archives: toxic

Sudan dye

Adulteration with Sudan Dye Has Triggered Several Spice Recalls

By Thomas Tarantelli
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Sudan dye

In the following article, the author reports finding Sudan dye in spices in New York State, making the argument for Class I recalls.

In New York State (NYS), Department of Agriculture and Markets food inspectors routinely sample domestic and imported food from retail markets for food dye determination. For decades, the NYS Food Lab has examined both domestic and imported food for undeclared allowed food dyes and unallowed food dyes utilizing a paper chromatography method. This method works well with water-soluble acid dyes, of which food dyes are a subset.

The NYS Food Lab has participated in four sets of the FAPAS proficiency tests: Artificial Colours in Soft Drinks and Artificial Colours in Sugar Confectionary (Boiled Sweets). The qualitative analysis was by paper, thin layer silica and thin layer cellulose chromatography. Satisfactory results were obtained.

The paper/thin layer chromatography method is a qualitative non-targeted method and has a limit of detection of approximately 1 to 5 ppm (parts per million) depending on the dye. If an unallowed dye is detected, the food product is violated as adulterated and results are forwarded to the FDA.

Some countries have a maximum concentration of allowed food dye in a food product. For example India has a 100 ppm to 200 ppm maximum for their allowed food dyes, in some food, singly or in combination.1

Sesame seeds, Rhodamine B
Early 2011, sesame seeds were found to contain Rhodamine B.

In early 2011, a food sample of pink colored sugar coated sesame seed from Pakistan was sent to the lab for color determination. The paper chromatography method could not determine any dyes. (As found out later, the unknown pink dye was not an acid dye.) From research it was found that Rhodamine B was a pink water soluble basic dye commonly used as a food adulterant.  A standard was ordered and then a qualitative high performance Liquid chromatography-tandem mass spectrometry (HPLC/MS/MS) method was developed (Waters UPLC Aquity w/Waters Premier XE triple quadrapole) to determine Rhodamine B. After utilizing this new method, Rhodamine B was found in the sugar coated sesame seed.

Rhodamine B is an industrial dye and is not allowed in food anywhere in the world. Industrial dyes are not allowed in food because they are toxic; in fact, some industrial dyes are used for suicide.2,3,4 In addition, industrial dyes are not made to “food grade” specifications with regard to dye purity, heavy metal (i.e., arsenic and lead) concentrations, subsidiary dye concentrations and concentrations of unreacted precursors. From additional research of news articles and research papers, more industrial dyes were identified as common food adulterants; more dye standards were ordered and incorporated into the HPLC/MS/MS method. The NYS Food Lab’s current HPLC/MS/MS surveillance method includes 36 compounds: Water soluble “acid dyes” and “basic dyes”, organic solvent soluble “solvent dyes”, and several pigments.

The HPLC/MS/MS method has a limit of detection in the ppb (parts per billion) range for some dyes and parts per trillion for other dyes. The FDA has an action level of 1 ppb for certain water-soluble basic dyes (such as Malachite Green) when used as a fish antibiotic. However, due to concern that unallowed dyes might be present due to contamination from packaging, the food lab subsequently set an action level of 1 ppm for unallowed dyes determined by the HPLC/MS/MS method. At levels over 1 ppm, detection of dyes in food would indicate intentional dye usage for coloring food.

The food lab has participated in three rounds of the FAPAS proficiency test, “Illegal Dyes found in Hot Pepper Sauce”. The qualitative analysis was by LC/MS/MS. Satisfactory results were obtained.

Sudan Dyes Considered to be Carcinogenic

“Sudan dyes are not allowed to be added to food. There has been worldwide concern about the contamination of chili powder, other spices, and baked foods with Sudan dyes since they may have genotoxic and carcinogenic effects (according to the International Agency for Research on Cancer)”.5

“There have been several documented cases of spices being contaminated with carcinogenic dyes such as Sudan I or lead oxide. We therefore assume that the presence of these chemicals in spice ingredients will be considered a reasonably foreseeable hazard under this rule.”6

“Sudan red dyes have been used to color paprika, chili powders, and curries, but are also known carcinogens and are banned for use in foods.” 7

Sudan Dyes are a family of more than 10 synthetic industrial “solvent dyes”. Solvent dyes are typically used to color oils and waxes, including shoe polish. Sudan dyes that the food lab has found in spices include Sudan 1 (Sudan I), and Sudan 4 (Sudan IV). Sudan 1, also known as Solvent Yellow 14, is an orange colored dye. Sudan 4, also known as Solvent Red 24, is a blue shade red colored dye.

Positive identification of Sudan 4 is often hindered by the existence of a positional isomer, Sudan Red B (Solvent Red 25). This problem was addressed by using the HPLC/MS/MS method with a transition unique to Sudan 4 (381.2 > 276.0). This information was obtained from one of the two corroborating labs. The food lab has recently identified a transition unique to Sudan Red B (381.2 > 366.1).

Sudan Dyes Found in Spices in Europe

In March 2001, Europe began discovering Sudan dyes in spices. A February 2017 search of Europe’s Rapid Alert System for Food and Feed (RASFF) for “unauthorised colour” and “sudan” in the “herbs and spices” food category resulted in 429 notifications.

The 429 RASFF notifications arranged by year and by maximum concentration reported of Sudan 1 and Sudan 4 during that year are listed in Table I.

Sudan dye
Table I.

In a search of the FDA’s Import Alert 45-02 (Detention Without Physical Examination and Guidance of Foods Containing Illegal and/or Undeclared Colors) the author could find no record of spices violated for Sudan dye adulteration.

In a search of the FDA’s Enforcement Reports the author could find no record of spices violated for Sudan dye adulteration.

Industrial Dyes in Food: Class II or Class I Recall?

The NYS Food Lab and the FDA routinely find imported food containing unallowed food dyes such as Ponceau 4R, Amaranth and Carmoisine. These unallowed food dyes are allowed for use in food in other parts of the world, while not allowed in the USA. Foods containing unallowed food dyes are violated as adulterated and a Class II recall will occur. Sudan dyes are not allowed as food dyes anywhere in the world. They are industrial dyes, used in coloring oils and waxes, such as shoe polish.

“Class I recall: A situation in which there is a reasonable probability that the use of or exposure to a violative product will cause serious adverse health consequences or death.

Class II recall: A situation in which use of or exposure to a violative product may cause temporary or medically reversible adverse health consequences or where the probability of serious adverse health consequences is remote.”8

With a Class II recall, there is no consumer notification. In contrast, as part of a Class I recall, a press release is issued. Consumers who have purchased the product might be informed and may discard the product or return it for a refund.

Continue to page 2 below.

BPA in canned food

Report: Food Companies Not Making Good on Vows to Halt BPA Use

By Maria Fontanazza
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BPA in canned food

The use of Bisphenol A (BPA) in bottles, canned foods, and even medical products has been hotly debated for more than a decade. The toxic chemical has been cited in numerous studies as a hormonal disruptor, contributing to a higher risk of asthma, certain types of cancers, type-2 diabetes, obesity, infertility, and attention deficit disorder, along with other health issues.

Buyer Beware
Nearly 200 cans were tested for the presence of BPA-based epoxy resins and other chemicals.

A report released today calls out “alarming” findings on the presence of BPA in canned foods. “Buyer Beware: Toxic BPA & Regrettable Substitutes in the Linings of Canned Food”, analyzed 192 canned foods, from fruits and vegetables to soups and gravy to milk for the presence of BPA and other chemicals.

“This report is meant to serve as a wake-up call for national brands and retailers of canned food who are jumping from the frying pan into the fire by elimi­nating BPA and potentially replacing it with regrettable substitutes,” the report’s authors state. “Consumers want BPA-free canned food that is truly safer, not canned food lined with chemi­cals that are equally or more toxic.”

The Good News

The following food companies are no longer using BPA, and the chemical was not found in any of the cans tested from:

  • Amy’s Kitchen
  • Annie’s Homegrown
  • Hain Celestial
  • ConAgra

“Our analysis showed that, across the board, canned food manufacturers both large and small are not making good on their promises to discon­tinue use of BPA.” – Buyer Beware: Toxic BPA & Regrettable Substitutes in the Linings of Canned Food

The Bad News

“Grocery stores, big box retailers and dollar stores are not doing enough to eliminate and safely replace BPA in their canned food,” according to the report.  About 62% of retailers’ private label canned food tested positive for BPA-based epoxy resins, including those from Albertsons, Dollar General, Dollar Tree, Kroger, Target (100%), Trader Joe’s, Walmart (88%) and Whole Foods. However, some of these retailers have adopted policies to lower BPA use in their cans. Whole Foods, for example, has stated that its buyers are not accepting new cans that have BPA in the lining. The report called out the following national companies for testing positive for BPA in its cans:

  • Campbell Soup Company: 15 out of 15 cans
  • Del Monte: 10 out of 14 cans
  • General Mills: 6 out of 12 cans
  • McCormick & Co: (Thai Kitchen). 3 out of 3
  • Nestle Carnation: 3 out of 3

According to the report, Campbell’s, McCormick and Nestle have stated that they will move away from using BPA either this year or in 2017.

Although some companies may have initiatives in place to halt the use of BPA-based epoxy in canned goods, some of the other substitutes could be harmful as well. Aside from BPA, the main types of coatings found among the tested cans were acrylic resins (some of which were polystyrene, which is a potential human carcinogen), oleoresin, polyester resin, and polyvinyl chloride copolymers (a known carcinogen, PVC was found in 18% of private-label cans and 36% of national brands).

The report recommends that manufacturers and retailers make a commitment (and provide a timeframe) to eliminate BPA from all packaging and find safe substitutes. This may be easier said than done considering there isn’t a wealth of data on the safety of BPA-epoxy substitutes. The authors called on industry to take several additional actions:

  • Accountability on the part of can-lining suppliers via public disclosure of the chemical composition of can linings, along with assessment of their effect on health
  • For Congress to adopt the “Ban Poisonous Additives Act”, which bans the use of BPA in food containers
  • Labeling of all chemicals used in liners

Twenty-two organizations in 19 states and Ontario, Canada participated in the report, which was produced by the Breast Cancer Fund, Campaign for Healthier Solutions, Clean Production Action, Ecology Center, Safer Chemicals Healthy Families’ Mind the Store Campaign, and Environmental Defence.

Rapid and Robust Technologies Improve Sample Preparation for Analyzing Mycotoxins

By Olga I. Shimelis
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Mycotoxins are produced as secondary metabolites by various mold species during the growth and harvest of grains, fruits, nuts and condiments. Their production is directly related to the dry/wet weather conditions during the growing season. Mycotoxins are very stable compounds and are not easily removed during storage, processing and preparation of raw agricultural commodities.

Mycotoxins & Grains
Mycotoxins can be found in a variety of grains.

Different classes of mycotoxins are distinguished on the basis of the structural similarity and originating mold species. For example, more than a dozen different aflatoxin compounds exist but only five of them are routinely tested (aflatoxins B1, B2, G1, G2, and M1). Aflatoxin B1 is of particular interest because it is listed as a Group 1 Carcinogen by the International Agency for Research on Cancer (IARC). Aflatoxin M1 is a metabolic product that can be present in milk upon ingestion of aflatoxin B1 by an animal. Aflatoxins are ubiquitous in important agricultural commodities including maize and peanuts, and are among the most studied mycotoxins.

Deoxynivalenol (DON) is produced by a different fungi species. It is prevalent in cereal crops grown under wet conditions and temperatures above 15o C (60o F). Chronic exposure of livestock to DON may result in slowed growth, impaired immune function and reduced rates of reproduction, particularly in non-ruminants.

Mycotoxins were discovered as the cause of poisoning outbreaks in both humans and farm animals in the mid-20th century. Since then, multiple government regulations were established to control the presence of these toxic compounds in food and feeds. For example, harvested grains are checked for mycotoxin contamination using rapid field screening methods prior to grain deposition into silos. If contamination is found, the crops are sent to an analytical laboratory to perform the confirmation analysis. Liquid chromatographic methods were often used for such analysis with both fluorescence and UV detection. In recent years, mass spectrometry has been employed as a detection method.

Sample Preparation for Laboratory Mycotoxin Analysis

When performing analysis, it is important to choose the right sample preparation method to ensure accuracy, sensitivity of detection, repeatability and robustness, as well as fast sample preparation for high throughput. During laboratory analysis of mycotoxins, the sample preparation procedure typically includes extraction, purification and concentration steps.

Extraction of mycotoxins from samples is conducted by mixing the ground sample with the mixture of organic solvent and water, such as acetonitrile:water (80:20). Using methanol is not recommended, because it does not provide complete extraction. Prior to cleanup, the sample is filtered. Historically, mycotoxin analysis required extensive extract cleanup to minimize interference by matrix components. This holds true as new regulations continue to require lower detection limits.

Cleanup methodologies often include the use of phase extraction (SPE). Of the different types of SPE, one of the most common is the use of immunoaffinity sorbents that result in the selective retention and cleanup of mycotoxins. The drawback to using the immunoaffinity sorbents in the lab is that they are not compatible with the mycotoxin extraction solvent. In order to load the extract into the immunoaffinity SPE tube, the extract must be diluted with water, sometimes 20-fold, to prevent precipitation or folding of the protein-based antibodies by exposure to organic solvent. This presents an additional sample preparation challenge, as the grain extracts tend to form precipitates upon the addition of water and can clog the SPE columns. Thus, apart from the high cost of immunoaffinity SPE columns, the methods tend to be labor and timeintensive.

Super Tox SPE cartridges
Super Tox is a line of SPE cartridges for mycotoxin families that eliminates extra sample prep steps.

It would be beneficial to a laboratory to eliminate these extra sample preparation steps required by immunoaffinity SPE. Such cleanup SPE procedures are available and can be applied directly to the mycotoxin extracts without the need for further dilution, filtration and evaporation. A line of SPE cartridges for different mycotoxin families was recently introduced to the market. These SPE cartridges are compatible with the extracts generated during mycotoxin extractions and can be stored at room temperature. The tubes can also be used for cleanup of multiple classes of mycotoxins.

Analysis of Aflatoxins and Zearalenone

SPE cartridges are available for aflatoxins and zearalenone.
SPE cartridges are available for aflatoxins and zearalenone.

The following results employed SPE cartridges for mycotoxins that can be used for two aflatoxin classes, aflatoxins and zearalenone, and were applied to the cleanup of grain and peanut extracts. Results were compared to cleanup using immunoaffinity columns.

AflaZea SPE cartridges are based on the “interference removal” strategy that requires fewer processing steps compared to the “bind-and-elute” strategy of the other SPE. Peanut extracts contain not only co-extracted protein and complex carbohydrates but also fat. This extract was successfully cleaned using AflaZea SPE. When the SPE tube and a leading IAC column were applied to the peanut extract, both methods demonstrated good recoveries for spiked aflatoxins B1, B2, G1, G2 with AflaZea recovery values of 101–108% and immunoaffinity recovery values of 79–100%. However, the AflaZea provided better reproducibility for detection with a relative standard deviation (RSD) of 2–4% RSD versus 10–25% RSD with immunoaffinity SPE. This is likely because sample preparation using AflaZea is less tedious and takes one tenth of the time compared to immunoaffinity SPE.

Analysis of Deoxynivalenol

Wheat samples can be analyzed for deoxynivalenol using a new SPE cartridge.
Wheat samples can be analyzed for deoxynivalenol using a new SPE cartridge.

The following compares a new SPE cartridge for the analysis of DON, one of the Fusarium mycotoxins, with immunoaffinity SPE. Analysis of DON often is conducted using liquid chromatography (LC) with UV detection, so sample cleanliness is important to permit the separation of the DON peak from background interferences. The new SPE DON cartridge was compared to the immunoaffinity SPE for the cleanup and analysis of wheat samples. Clean chromatography and good recovery of spiked DON was obtained by both methods (86–97% RSD). However, clogging of the filters by the immunoaffinity SPE sample was observed during cleanup and complicated the sample preparation procedure. The SPE DON cartridge provided faster sample preparation.

Analysis of Patulin

Patulin is a mycotoxin commonly found in rotting apples.
Patulin is a mycotoxin commonly found in rotting apples.

Another SPE technology for mycotoxin analysis is based on molecularly imprinted polymers (MIPs), which are sometimes called “chemical antibodies” and mimic the performance of immunoaffinity sorbents. MIPs have binding sites that conform to the shape and functionality of specific compounds or compound classes. Strong binding of the analyte to the MIP makes it possible to perform intensive SPE washes that lead to very clean samples. Unlike immunoaffinity sorbents, MIPs are compatible with organic solvents and strong acids and bases.

Foods containing apples and similar fruits are required to be tested for patulin toxin, as they are the most common source for patulin exposure in humans. The MIP SPE procedure for patulin is faster than other SPE or liquid-liquid extraction methods and provides selective retention and superior cleanup. It is a robust method for analyzing apple juice and apple puree with HPLC-UV detection. After cleanup, patulin is quantified in apple puree at 10 ppb levels, which meet most regulatory requirements. The MIP SPE cleanup method eliminated 5-(hydroxymethyl)furfural (HMF) from the matrix, which sometimes appears as an interfering chromatographic peak when other sample prep methods are used. An SPE wash using sodium bicarbonate removed the interfering organic acids, while patulin was stabilized during elution at the end of the SPE procedure by using acidified solvent. Thus, most problems encountered during patulin analysis were resolved during this single SPE procedure.

Conclusion

As government regulations and consumer demand warrant cleaner, non-contaminated products, mycotoxin analysis will continue to be performed around the world. Careful selection of sample preparation methods is required for such analysis to achieve accurate testing results, best method performance and high laboratory throughput. Although many sample preparation methods exist, laboratories should choose the methods that not only provide adequately prepared samples, but also result in time and cost savings. The SPE technologies discussed in this article are sample preparation techniques that provide the required analytical sensitivity without capital expenditure into higher-end LC-MS equipment; the LC-UV and LC-FL methods can still be used. In addition, these SPE methods are simple, more robust, and less-time consuming compared to other SPE methods or liquid-liquid extraction.

All images courtesy of Sigma Aldrich