There's a lawsuit in the works that might make Soylent investors a bit queasy.

Last week, environmental health watchdog As You Sow filed a notice of intent to bring legal action against meal replacement company Soylent. As You Sow claims that Soylent's powdered product, Soylent 1.5, contains unsafely high levels of lead and cadmium and lacks proper warnings, violating California's Safe Drinking Water and Toxic Enforcement Act.

"These heavy metals accumulate in the body over time and, since Soylent is marketed as a meal replacement, users may be chronically exposed to lead and cadmium concentrations that exceed California's safe harbor level (for reproductive harm)," Andrew Behar, As You Sow's CEO, said in a statement. "With stories about Silicon Valley coders sometimes eating three servings a day, this is of very high concern to the health of these tech workers."

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On Monday, Soylent posted on the company blog to deny allegations of unusual or unsafe levels of lead, cadmium or any metal. The company noted that As You Sow's planned lawsuit was not focused on whether the product passes health and safety regulations, but whether the company properly displays warnings. According to Soylent, it does.

"Soylent’s levels of heavy metals are entirely safe and sustainable, even for people using Soylent as a complete food substitute," Soylent's blog post reads. "Trace amounts of lead and cadmium are present everywhere, including drinking water, which is why the FDA and EPA set strict exposure limits."

Due to Proposition 65, California has more stringent legislation regarding heavy metals than most states. While Soylent claims that products easily meet standards set by the FDA, the EPA and the WHO in terms of lead and cadmium, the levels of heavy metals require a warning label under California law.

Soylent has become a trendy replacement for food in entrepreneurial circles. The company recently announced that in October, it will release Soylent 2.0, a pre-bottled variant on its current, mixable powder form (Soylent 1.5).

Related: Soylent Announces Next Generation Meal Replacement Will Arrive Pre-Bottled