Pesticide Testing: NSF International updates dietary supplement certification standard

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14 Aug 2018 --- NSF International and the NSF/ANSI 173 Joint Committee have updated the pesticide testing requirements included in NSF/ANSI 173, the only American National Standard for dietary supplements. A recent NSF study established chemical-specific pesticide limits for 185 pesticides that might be present in botanical ingredients used in dietary supplement ingredients.

“The new testing requirements fill an important gap,” said Rebecca Adams, the NSF International research toxicologist who led the study. “Pesticides lacking residue limits are currently held to a ‘precautionary zero tolerance’ which has moved closer and closer to zero over time as analytical testing methodologies have advanced. NSF International’s evidence-driven approach minimizes reliance on zero tolerance while remaining protective of public health and safety.”

NSF International’s new pesticide criteria give supplement manufacturers a scientifically valid way to demonstrate regulatory compliance and their commitment to quality and safety. “What’s important is that these criteria provide a tool for industry to evaluate pesticide residues in botanical ingredients used in dietary supplements,” said Sylvia Laman, Managing Toxicologist at NSF International. “By using EPA and international data we’ve been able to develop scientifically defensible chemical-specific pesticide limits.”

The updates to the testing requirements follow months of comprehensive research by NSF International toxicologists, who used US Environmental Protection Agency (EPA) health effects criteria as well as criteria from international authorities as the basis to develop scientifically defensible chemical-specific limits for each pesticide, including the fungicides difenoconazole and oxidixyl and the insecticide dieldrin. This update to NSF/ANSI 173 should not be considered a substitute for U.S. Food and Drug Administration (FDA) pesticide residue requirements which, while written specifically for food products, remain an FDA compliance requirement for supplement manufacturers.

NSF International facilitated the development of NSF/ANSI 173, which is continually updated with the changing industry. Today, more than 1,000 supplement products and ingredients are certified to NSF/ANSI 173 by NSF International. To earn NSF International certification, supplements must be produced in a manufacturing facility that is inspected twice a year to meet the US FDA’s Good Manufacturing Practice (GMP) requirements. Supplements are tested to verify product formulation and label claims and for a battery of specific contaminants and adulterants. After initial certification, the manufacturing process and the product are regularly audited and annually tested to verify compliance.

NSF International is an independent, global organization that facilitates standards development, and tests and certifies products for the dietary supplements, food, water, health sciences and consumer goods industries to minimize adverse health effects and protect the environment. 

NSF International facilitated the development of the only American National Standard (NSF/ANSI 173) that verifies the contents of dietary supplements and also tests and certifies products to this standard. In North America, NSF International’s Certified for Sport program, which builds on NSF/ANSI 173 but also screens for substances prohibited in sport is required or recommended by Major League Baseball, the National Hockey League, the National Football League, PGA, LPGA and the Canadian Centre for Ethics in Sport (CCES).

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