When it comes to what we eat and drink on a daily basis, quality matters. The ingredients in a product influence how we feel and perform, and can dictate what contaminants we come into contact with.
The same is true for the electrolytes we consume. We all need electrolytes in some form to survive: They help our hearts beat, nerve impulses fire, and muscles contract. When we don’t consume enough, we can get tired, crampy, and experience brain fog — which is why we formulated LMNT the way we did, to fill in nutritional gaps on whole foods diets and help replace sweat sodium losses.
Quality matters for these electrolytes. Since these minerals come from the earth and sea, contaminants like heavy metals can be inadvertently sourced alongside them. This is why we’re intentional and diligent with sourcing and product testing at LMNT: So that we can be confident sharing LMNT Drink Mix and LMNT Sparkling with our loved ones (even when they snatch the last cold one from the fridge…ahem) — and so that you can feel confident you’re choosing a truly healthy hydration option.
In this article we’ll dive into our quality assurance system to provide insight into the main questions we get about how we source, test, and address safety concerns (including heavy metals and Prop 65). If you’re curious about something we don’t cover here, reach out to us — we want to help you feel confident in your nutrition choices.
Heavy Metals in Salt
Heavy metals are everywhere — in the earth, in plants (which absorb heavy metals through their roots), in animals (which eat the plants). As such, they’re present in most foods, including salt.
Some of these metals, like iron and zinc, are actually necessary for our bodies to function. However, others — like arsenic, lead, cadmium, chromium, and mercury — serve no biological function and are toxic at relatively low doses. For instance, excessive lead exposure (typically from lead paint) has been linked to cognitive impairment, kidney problems, and other health issues.
Although these metals may be present in most foods, it’s important to think in terms of tradeoffs. For example, leafy greens (like spinach) and root vegetables (like carrots) can carry a higher heavy metal content depending on where they’re grown — and yet these are among the healthiest food choices one can make. Eating whole foods diets of meats, nuts, fruits, and vegetables like our ancestors did, rather than ultra-processed foods, tends to improve (not worsen) human health. The human body also excretes some heavy metals through sweat, urine, and feces.
Yet some foods do have concerning levels of contamination. Salt can be on that list.
For instance, one 2023 study analyzed ten unrefined gourmet salts (Himalayan salt, black salt, sea salt, and others) from an Italian market. Every salt exceeded European maximum permitted lead levels of 2 mg/kg. For context, it would only take 1 gram of any of these salts to 10x exceed the ultra-conservative lead limits set by California’s Prop 65 — limits with which LMNT complies (more on that below).
Other research found heavy metals (lower levels than the Italian study) in 31 brands of commercial pink salt, and a 2011 Iranian study found unsafe levels of lead and mercury in various table salts.
The takeaway is that no type of salt is necessarily free of heavy metals. To play it safe, you can verify your salt brand’s sourcing, manufacturing, and testing process. On that note, let’s look at LMNT’s sourcing process.
How LMNT Sources Salt
Most of the world’s salt comes from modern seas or ancient sea beds that have dried up. A smaller percentage comes from lakes or dry lake beds, but for the most part, the salt you buy originated in the sea.
There are three main ways salt is sourced: Blast mining, excavation mining, and evaporation.
Blast mining uses controlled explosions to release salt from the earth. Unfortunately, blast residue can contaminate the salt and end up in the finished product.
Excavation mining is a much gentler process that uses friction and other methods to harvest salt from the earth. There’s no blasting and no blast residue.
Finally, you can source salt by evaporating salt water from the sea or salt springs. Evaporation has the lowest chance of cross-contamination with mining materials, but the salt will still contain whatever is in the sea. Some waters, of course, are cleaner than others.
LMNT sources our salt through a variation on this last method, called solar evaporation. We then refine our salt to remove impurities like heavy metals.
After sourcing comes testing, but before we delve into our testing process, let’s explore the strict standards we uphold.
Compliance with Prop 65
A few decades ago, Californians voted to pass the Safe Drinking Water and Toxic Enforcement Act of 1986, colloquially known as Prop 65. Prop 65 requires that businesses inform Californians if their product (food, clothing, fertilizer, etc.) contains any of about 900 chemicals linked to cancer, congenital disabilities, or other reproductive problems.
The detection limits are stringent. For example, Prop 65 requires a warning label if a product contains over 0.5 micrograms of lead per maximum daily usage. California’s Office of Environmental Health and Hazard Assessment (OEHHA) calculated this limit (and other Prop 65 limits) by taking the exposure level of a given chemical with “no observable effect” for causing reproductive toxicity (based on existing science) and then dividing that level by 1,000. In other words, complying with Prop 65 requires having super low levels of harmful chemicals — 1,000x lower than science suggests is safe.
Being aware of Prop 65’s limits can be helpful, but again it’s important to consider tradeoffs. If we circle back to those leafy greens we mentioned above, a single serving of spinach can have up to 5 mcg of lead, depending on where it’s grown — 10x exceeding Prop 65’s lead limits. Yet spinach is one of the healthiest foods we can eat, packed with vitamins like A, K, and C, iron, folate, and magnesium. Context matters.
Prop 65’s ultra-conservative approach is unique to California. The FDA has published a more reasonable “interim reference level” of 12.5 mcg lead per day for “women of childbearing age” (generally defined as premenopausal women who can become pregnant). This limit has not been linked to adverse effects. Nonetheless, we only release LMNT if it meets all defined product specifications and regulatory standards, including Prop 65 requirements. Let’s talk testing.
Our Testing Process
All of our manufacturing facilities are either SQF or NSF certified, and all are Good Manufacturing Practices (GMP) certified.
We test every lot of LMNT with third parties for heavy metals, bacterial contamination, and mineral content (sodium, potassium, magnesium), and a Certificate of Analysis (COA) is received from the third party certifying the test results. We also test for flavor, texture, and overall consistency. Sampling LMNT all day is tough work, but someone has to do it!
We test at multiple points in the production process. Our raw materials are tested first by the supplier and arrive with COAs that meet our specifications; if they do not meet the specifications, the materials are rejected. We also test the bulk mix of blended raw materials, and then the finished LMNT Drink Mix stick packs and Sparkling cans themselves.
If it’s not clear already: We test extremely carefully. We drink LMNT ourselves daily, and we share it with our kids, parents, and friends. We make sure that every stick pack and can has a purity, quality, and consistency we can stand by as we help our community hydrate for better health.
Our Commitment to You
When you purchase LMNT, you know exactly what you’re getting. You’re getting an electrolyte drink that’s been thoughtfully sourced and diligently tested for impurities and quality. Every time.
All this rigor reflects our commitment to you — not an abstract commitment, but a personal one. The cans and stick packs we sell are the same we drink ourselves and share with our loved ones. Enjoy LMNT in good health — and Stay Salty.
