Factories, refineries and other industrial facilities in New Jersey released almost six million pounds of toxic chemicals into the state’s air, water and land in 2017, according to newly published federal data.

And that’s actually an improvement for the Garden State.

On Tuesday, the U.S. Environmental Protection Agency released its Toxics Release Inventory (TRI) for 2017. The TRI tracks what types of chemicals were released by industrial sites into air and water across the country, how much of those chemicals were released and which sites they were released from.

According to the TRI, industrial sites in New Jersey released 5.8 million pounds of toxic chemicals in 2017. That’s a more than 260,000 pound improvement from 2016, and the lowest amount of chemical releases in the Garden State since at least 2003.

The sites releasing chemicals into New Jersey’s environment were scattered across the state, with the heaviest polluters being clustered in industrial areas near the Arthur Kill in the Northern part of the state, and the Delaware Bay in the Southern half.

Nitrate compounds were by far the most released chemical in New Jersey in 2017, with more than 4.7 million pounds of the stuff being sent into the state’s environment. According to the EPA, nitrates made up 99 percent of the chemicals released into New Jersey water that year.

Though most people are not exposed to extreme concentrations of nitrates, at high enough levels the chemicals can cause decreases in blood pressure, increased heart rate, reduced ability of the blood to carry oxygen to tissues, vomiting and even death, according to the Centers for Disease Control and Prevention.

A much larger variety of chemicals made up New Jersey’s industrial air pollution in 2017. The state’s leading industrial air pollutant was ammonia, which according to the TRI made up 18 percent of chemicals released into the air by Garden State facilities.

Exposure to high levels of ammonia can cause respiratory problems, according to the EPA.

Lead, which even in low amounts can stunt growth in children, according to the EPA, and chromium, which can cause respiratory problems according to the CDC, were also among the top chemicals released in the Garden State in 2017.

The bulk of New Jersey’s toxic chemical releases came from a few facilities in 2017. The biggest source of chemical releases in the state was the Phillips 66 Bayway Refinery in Linden, which released more than 2.8 million pounds of chemicals into the Garden State’s environment that year.

With the decrease in chemical releases from 2016 to 2017 continuing a trend in the decline of pollution, the EPA praised the numbers, both in New Jersey and across the nation, as proof that industry has grown with minimal environmental impacts.

“The latest TRI analysis confirms that under President Trump the U.S. continues to improve its air quality while growing its economy,” said EPA Administrator Andrew Wheeler.

But environmental groups, like the New Jersey Sierra Club, saw less to be excited about in the numbers.

“Even though there has been a decline in air pollution from 2016, many urban and environmental justice communities are still suffering from this air pollution," said Jeff Tittel, the director of the New Jersey Sierra Club. "Most of the decline in total and air pollution since 2016, which is not a lot, has been based on companies closing or switching to another use.

Michael Sol Warren may be reached at mwarren@njadvancemedia.com. Follow him on Twitter @MSolDub. Find NJ.com on Facebook.

Erin Petenko may be reached at epetenko@njadvancemedia.com.Follow her on Twitter @EPetenko. Find NJ.com on Facebook.

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