An environmental group has filed a notice of its intent to sue the city of Newark over what it says are elevated levels of lead in the city's drinking water.

The Natural Resources Defense Council has 60 days to file a lawsuit.

The group cites a federal report that says Newark's lead levels are among the highest in the country for systems serving over 50,000 people. Exposure to low levels of lead has been linked to damage to the nervous system, learning disabilities and impaired formation of blood cells.

The NRDC says that they have looked at data from 2017 and when it comes to the city’s drinking water, they found that 10 percent of samples collected by the city’s water department had lead levels in excess of 26-parts-per-billion. This is about double the federal action level of 15-parts-per-billion.

But Newark officials say that the water supplied by the city is fully compliant with federal and state regulations.

In a statement officials said that the NRDC’s report “is absolutely and outrageously false…The claimant has seriously misinterpreted the findings."

The city of Newark did have to address high lead levels in schools in 2016. But this was due to lead fixtures in water fountains and sinks. Those fixtures have since been replaced. The city is also helping homeowners whose lead service lines need to be replaced because they're causing contamination.

The NRDC’s potential lawsuit also names the New Jersey Department of Environmental Protection. A spokesperson for the DEP says that they are reviewing the claims.