Defending Against Adulteration in the Herbal Products Industry

Economically-motivated adulteration of commodity raw materials remains a persistent global challenge in many industries, including foods and beverages, pharmaceuticals, cosmetics and personal care, and dietary supplements.

Alongside awareness and a commitment to quality, supply chain transparency and fit-for-purpose analytical testing can help supplement brands stay ahead of the curve. Especially as cost pressures rise from a higher tariff rate on Chinese goods, creating the potential for further adulteration, understanding what to watch for can help brands ensure integrity of their products.

Awareness and Action 

“We are very concerned about the quality of some of the botanical dietary supplements that are available on the U.S. and global markets,” said Stefan Gafner, PhD, chief science officer at the American Botanical Council (ABC). “While there are many great manufacturers that make high-quality products, peer-reviewed publications have consistently shown that a portion of the botanical dietary supplements available on the market are adulterated.”

This is the main reason that ABC, the American Herbal Pharmacopoeia (AHP), and the National Center for Natural Products Research (NCNPR) at the University of Mississippi joined forces in 2011 to form the Botanical Adulterants Prevention Program (BAPP) as an information resource on this topic. “Unfortunately, BAPP has not run out of work yet,” said Gafner, who serves as director of the program.

“Adulteration in botanical supply chains is one of the most serious threats facing our industry today,” said Shaheen Majeed, global CEO and managing director, Sabinsa. “While I’m confident in Sabinsa’s rigorous sourcing and testing protocols, the broader commodity botanical market presents significant risks that concern me deeply.”

Issues often start with aggregated materials that lack proper chain of custody documentation, Majeed said. “These create perfect opportunities for sophisticated adulteration schemes. We’re seeing everything from economic adulteration with cheaper plant parts to dangerous contamination with synthetic compounds or undeclared allergens. The financial incentives are enormous when you can dilute premium botanicals with worthless fillers.”

Some adulteration methods have become increasingly sophisticated, he added, requiring advanced analytical techniques to detect. “This is why partnerships with experienced testing laboratories, whether in-house or contract, are critical. These labs need deep industry knowledge to know what adulterants to look for and which analytical methods will catch them.”

In nearly 30 years running Alkemist Labs, a botanical and fungi testing lab, CEO Elan Sudberg said his company has seen “a steady decline in overt adulteration.”

“That said, I always am and likely always will be concerned about adulteration in the supply of herbal ingredients. As the industry trends change, so does the demand for particularly challenging-to-source ingredients.”

He called the situation “an ever-moving target” that warrants working with “a lab that specializes in the botanical/fungal arena and has early warning about the latest risky material.”

Overall, the herbal supplement market’s quality spectrum is “stark,” said Majeed. “On one end, you have branded, research-backed botanicals with patents, transparent sourcing, and comprehensive safety data. On the other hand, generic materials with no origin documentation, no testing, and no accountability. This disparity doesn’t just create unfair competition; it actively undermines consumer trust when substandard products fail to deliver promised benefits.”

The solution, he continued, “requires industry-wide commitment to transparency, robust testing protocols, and prioritizing quality over short-term cost savings.” Otherwise, the herbal supplement industry risks its credibility. “Consumers deserve ingredients that work, and the science-backed botanicals that can deliver those results.”

Unfortunately, some brands and contract manufacturers are only interested in buying the cheapest raw material that will pass basic testing, said Cal Bewicke, CEO, Ethical Naturals Inc. (ENI).

“There are a number of suppliers who import the cheapest material they can, do no testing in the U.S., and use only the original manufacturer’s testing data as a quality assurance guarantee. That is no guarantee. This system now supplies a high percentage of botanical extracts, meeting the demand for the lowest price.”

These practices have a high cost, though, he added. “First of course, there are the consumers who buy and use these products for the health benefits that have been demonstrated in clinical trials and studies; but these botanicals are only effective if they contain the full spectrum and potency of active ingredients in therapeutic amounts.”

Additionally, in a market with cheap, adulterated products, Bewicke said, “it makes it much harder for suppliers and brands who do real testing, selling real products, to do their work and be successful in their businesses.”

“Frankly,” he added, “this battle has been fought by ethical companies for decades, and it shows no sign of going away.”

Meanwhile, Majeed said, “the commodification of research-backed botanical ingredients represents one of the most dangerous trends in our industry. When brands source ‘equivalent’ versions of clinically studied ingredients, they’re making a fundamental error in assuming research conducted on a specific, standardized material applies to generic alternatives. This is scientifically invalid. Clinical studies on a particular curcumin extract with defined specifications don’t magically transfer to aggregated material from multiple sources using different processing methods.”

Brands buying commoditized curcumin, which typically lack the specific curcuminoid ratios, “are essentially conducting uncontrolled experiments on consumers, using ingredients that may bear little resemblance to what was studied in clinical trials,” Majeed said. “Not every ingredient needs to be branded, but it does mean rethinking procurement strategy. Excellent unbranded suppliers exist, but they’re characterized by transparency, consistent quality systems, and genuine partnerships, not just competitive pricing.”

Impact of Tariffs

Given high tariff rates on material imported from China, the risk for adulteration in botanicals is higher, experts noted. 

Speaking about the integrity of botanical raw materials, Gafner said, “if we take past events as a blueprint, e.g., the Covid-19 pandemic, we can anticipate that the sudden and massive increase in the price of botanical ingredients will lead to an increase of adulterated materials at lower cost to be offered. While we have no evidence for an increase in adulteration due to the tariffs at this time, we expect that the volume of adulterated botanical ingredients offered will rise.”

Sudberg also said that so far he’s only heard of “potential and hypothetical threats” related to tariffs. “None of our clients have shared any real hardships with us, yet. Since we work with only the best of the best they usually have backup sources already qualified, ready to go. That said, just like during the pandemic, when ingredient supplies are actually strained, many in our industry perilously buy from new, unknown sources, and if they don’t adequately qualify the materials the adulteration will go up.”

Wilson Lau, president of Nuherbs noted the tariff rate for herbs from China is currently (as of late June) 55%. “This means if something fails identity or quality testing and needs to be returned, there is a huge cost consequence to the exporter. They have to be extra careful, otherwise the penalties that they face may be extremely high. This is more true for unprocessed botanicals than extracts. So, while the tariffs are not exactly a good thing, their impact poses a higher risk for suppliers of lower or unknown quality material than for a company like Nuherbs that has an extensive quality program in place.”

According to Majeed, tariffs are creating “dangerous cost pressures that push companies toward risky sourcing decisions.”

When ingredient costs spike, brands face a tough choice, he said: “absorb increases, pass costs to consumers, or switch to cheaper suppliers. That third option is where adulteration risks spike.”

“We’re seeing established supplier relationships abandoned for unknown entities offering pre-tariff pricing,” Majeed added. “Desperate buyers overlook red flags, and unscrupulous suppliers exploit this vulnerability. It’s a perfect setup for quality disasters. What appears to be simple cost-saving triggers complex problems: 1) new documentation and potential label changes, 2) untested suppliers may lack capacity or realistic minimums, 3) different processing methods alter product performance, and 4) quality issues destroy years of brand building.”

Manufacturers will find that so-called “equivalent” ingredients don’t work the same as branded, standardized counterparts, forcing costly reformulations. “Others can’t meet demand when new suppliers fail to scale. Materials that test fine initially, but later reveal contamination when tested more thoroughly, are a big concern.”

Companies should use tariff pressure to “strengthen supply chains by negotiating with trusted suppliers, giving regular forecasting updates, exploring domestic alternatives, and securing longer-term pricing stability. The companies treating this as a temporary pricing problem will create permanent quality problems.”

Bewicke noted that tariffs have created shortages of botanical extracts and other raw materials. “When this happens, costs go up and many companies buy whatever they can to fulfill their obligations and keep products on the shelf without losing money. This creates more opportunity for companies who can go low on price and quality guarantees.”

Assessing Adulterated Material

Given the threat of adulteration, which herbal ingredients are more commonly adulterated, and what else can stakeholders do to recognize problems?

Twice a year Alkemist shares data it’s collected in a report titled “Herbs & Fungi We’re Watching,” listing ingredients that most frequently failed identity testing in its lab. The company’s  latest list, organized alphabetically by Latin name (and common name), includes the following:

• Angelica sinensis (Dong quai),
• Beta vulgaris (Beet),
• Camellia sinensis (Tea),
• Cinnamomum verum (Cinnamon),
• Ganoderma lucidum (Reishi),
• Hericium erinaceus (Lion’s mane),*
• Malpighia sp (Acerola),
• Matricaria recutita (Chamomile),
• Melissa officinalis (Lemon balm),*
• Origanum vulgare (Oregano),
• Passiflora incarnata (Passionflower),
• Rhodiola rosea (Rhodiola),*
• Siraitia grosvenorii (Luo han guo/Monk fruit),*
• Stevia rebaudiana (Stevia),*
• Taraxacum officinale (Dandelion),*
• Trametes versicolor (Turkey tail),
• Urtica dioica (Nettle/Stinging nettle),
• Valeriana officinalis (Valerian),
• Vitis vinifera (Grape), and
• Withania somnifera (Ashwagandha).*

* Denotes repeat offenders

Common names are as listed in the American Herbal Products Association’s (AHPA) Herbs of Commerce 3rd Edition.

“The frequency of adulteration for each botanical is very difficult to assess, and changes from year-to-year,” said Gafner. “As an example, in the 2000s, elderberry extracts were used to adulterate bilberry extracts as the latter were much more expensive. After elderberry became a very popular ingredient, especially in the U.S. starting in the years after 2017 and especially at the beginning of the Covid-19 pandemic, elderberry prices started to soar, while the available volume of high quality extracts was small. Partly because of this, elderberry extracts are now subject to adulteration with lower cost black rice extracts.”

A recent analysis from BAPP published in the journal Natural Products Reports in 2024 compared adulteration rates of ginkgo leaf extracts, elderberry extracts, echinacea herb and root powder and extracts, black cohosh root/rhizome powder and extracts, and turmeric root/rhizome powder and extracts. Based on that report, Gafner said, “it appears as if ginkgo leaf extracts are the most frequently adulterated material, followed by black cohosh.”

“Other botanicals with reportedly high adulteration rates are the cordyceps fungus, bilberry, and rhodiola root/rhizome,” he added. “High adulteration rates are also seen within the essential oil market. But reliable data on the extent of adulteration are lacking.”

Alongside ginkgo, elderberry, and Lion’s mane, Bewicke noted saw palmetto and resveratrol as ingredients that are often subject to adulteration.

Ginkgo is an ideal target for adulteration, he said, noting that it’s expensive to produce and relatively easy to adulterate in ways that will pass basic testing. “As a result, the extent of documented adulteration is extraordinary. For example, a study using sophisticated testing methods, and published in Journal of Herbal Medicine (June 2016) found that 33 out of the 35 products tested were adulterated. An American Botanical Council report (May 2022) reviewed studies that tested over 500 ginkgo samples and found that 242 were adulterated.”

According to Majeed, the most vulnerable botanicals are those experiencing rapid demand growth or supply disruptions. “We’ve seen this pattern repeatedly across the industry,” he said. “Curcumin was a perfect case study. When mainstream acceptance exploded, largely driven by clinical research on ingredients like our Curcumin C3 Complex, we suddenly saw impossibly cheap ‘curcumin’ flooding the market. Testing revealed some samples were 43% synthetic compounds masquerading as turmeric-derived curcumin. This synthetic adulteration is particularly insidious because it can slip past routine analytical testing.”

Ashwagandha is currently experiencing the same vulnerability, he continued. “With double-digit growth in recent years, we’re seeing classic red flags: price volatility, supply chain disruptions, and quality inconsistencies. That’s why we developed Shagandha, standardized to USP-NF monograph specifications to ensure authentic, consistent withanolide content.”

“High-value botanicals like ginseng, rhodiola, and milk thistle are also frequent targets because the economic incentives for adulteration are substantial,” Majeed said. “A few common schemes include synthetic substitution, species substitution using cheaper, related plants, dilution with inert fillers, and marker compound spiking to boost analytical results.”

Sophisticated adulteration often requires advanced detection methods, said Majeed. “For instance, distinguishing plant-derived compounds from synthetic versions requires carbon isotope analysis, which is not something caught in standard testing protocols.”

“When a botanical gains scientific credibility and market traction, adulterators follow the money,” he added. “The industry’s best defense is working with suppliers who maintain complete chain of custody documentation and invest in comprehensive analytical testing that goes beyond basic identity and potency verification.”

Tips and Tools

Lau offered three tips for brands to combat adulteration: “1) establish clear specification sheets to share with everyone involved, so everyone is on the same page, 2) build relationships with your suppliers versus looking at the cheapest per unit cost; because it’s not invoice price, but the total cost of ownership that matters, and 3) trust, but verify.

Bewicke advised companies to buy ingredients that have full U.S. testing data to support their quality assurance, and to work with reputable suppliers. “Avoid those suppliers who can’t document a chain of custody or provide detailed U.S. testing on their material. If you don’t have your own well-established laboratory, send samples to a highly regarded third-party testing lab to confirm identity, purity, and potency.”

Generic labs may miss sophisticated adulteration schemes, Majeed said, so industry-connected labs should be valued. “Labs deeply embedded in the botanical industry share intelligence about emerging adulteration methods and know which analytical techniques will catch the latest tricks. Test beyond basic specifications. Standard identity and potency testing isn’t enough. Consider carbon isotope analysis to detect synthetic substitution, DNA barcoding for species verification, and comprehensive contaminant screening.”

Sudberg said brands should “test, test, test, and then test some more. Don’t buy anything without a Certificate of Analysis (CoA) from a reputable lab with ISO 17025 accreditation for the specific testing needed. Then send that sample to another reputable lab with ISO 17025 accreditation for the specific testing needed. Labs should provide fully transparent CofAs and offer technical support without extra fees or hassle.”

Often, a simple look at a CoA is enough to spot an ingredient of low quality, said Gafner. “And yet, relying simply on CoAs can be misleading, as we have seen cases of fraudulent CoAs offered by a supplier.”

There are several other important issues to consider, according to Gafner. “One is to deal with a reputable supplier who can transparently document its supply chain, processing steps, standardization, and has a robust and appropriate quality control in place. Longer-term agreements with the same supplier tend to provide good results as this gives both supplier and manufacturer some security about volume needs and pricing, and helps to establish trust. With regards to pricing, ingredients offered at a substantially lower cost than the fair market value for high-quality powders and extracts should be viewed as suspicious.”

A thorough supplier audit, including a review of the company’s history of quality shortcomings, can be helpful, Gafner said.

“Being aware of the specific risks of adulteration, including price ranges, origin of authentic materials, processing steps, and known adulterants for a particular ingredient is also important,” he said. “BAPP has published reviews of adulteration (which we call bulletins) for 30 botanical ingredients, with the Echinacea Botanical Adulterants Prevention Bulletin being finalized.”

If a botanical of interest has not yet been covered in a bulletin, Gafner said there are many other scientific publications detailing adulteration for specific botanicals, “although such literature searches can be very time-consuming.” To deal with this issue, BAPP publishes its “Botanical Adulterants Monitor” newsletter, which summarizes reports for quality control personnel, three times per year.

Other BAPP resources include Laboratory Guidance Documents, which examine analytical methods for their usefulness to detect adulteration.

For manufacturer-supplier contracts, Gafner said, “implementation of the BAPP Best Practices SOP for the Disposal/Destruction of Irreparably Defective Articles should be considered by responsible parties in the botanical supply network.”

Ultimately, due diligence is paramount, Majeed said. “I doubt anyone who’s been in this industry long would let their families use products from brands that simply buy the cheapest ingredients available. That same vigilance needs to apply to every sourcing decision.”

Thorough vetting of suppliers is also critical, he continued. “Don’t just look at certificates; investigate their history, visit facilities when possible, and understand their testing protocols. At Sabinsa, we welcome facility tours because transparency builds trust. When suppliers are hesitant to show you their operations, that’s a red flag.”

Companies should also demand “complete chain of custody documentation,” Majeed said. “This should trace ingredients from field to finished product, including harvest dates, processing methods, and every hand the material passes through. Aggregated materials with gaps in documentation are where adulteration typically occurs.”

During supply disruptions, suppliers prioritize customers who’ve invested in long-term relationships, he added. “Companies that treated sourcing as purely transactional found themselves scrambling during recent shortages.”

Companies might also consider vertical integration where possible. “The more touchpoints you control, from raw material to finished product, the less opportunity for adulteration,” Majeed said. “This is why Sabinsa invested in end-to-end capabilities: farms, manufacturing, testing, and now consumer brands.”

“Quality costs more up front,” he added, “but protects your brand’s reputation and consumer trust. One adulterated ingredient can destroy years of brand building. Smart companies view comprehensive testing and supplier partnerships as insurance, not expense.”

Saving a few dollars per kilogram seems attractive until you consider the real risks, Majeed said: regulatory exposure (using ingredients that don’t match published research); efficacy failures (products that don’t deliver expected benefits); safety incidents (one serious adverse event from adulterated material can devastate entire categories); and brand damage (news of quality issues can spread faster than ever on social media).

“The industry’s future depends on elevating quality over cost, research integrity over generic equivalence, and partnership over price,” Majeed said.