THC Found In Trayvon Martin System

(CNN) -- Trayvon Martin had drugs in his system when he was fatally shot earlier this year by George Zimmerman in Sanford, Florida, according to autopsy results released Thursday.

Martin's blood contained THC, which is the psychoactive ingredient in marijuana, according to an autopsy conducted February 27 -- the day after the teenager was shot dead.

Toxicology tests found elements of the drug in the teenager's chest blood -- 1.5 nanograms per milliliter of one type (THC), as well as 7.3 nanograms of another type (THC-COOH) -- according to the medical examiner's report. There was also a presumed positive test of cannabinoids in Martin's urine. It was not immediately clear how significant these amounts were.

Concentrations of THC routinely rise to 100 to 200 ng/ml after marijuana use, though it typically falls to below 5 ng/ml within three hours of it being smoked, according to information on the National Highway Traffic Safety Administration's website.

While some states have zero-tolerance policies for any drug traces for driving while impaired, others set certain benchmarks, the website of California's Department of Alcohol and Drug Programs notes. In Nevada, that equates to 2 ng/ml for THC and 5 ng/ml for THC-COOH -- also known as marijuana metabolite. The cutoff level in Ohio is 2 ng/ml for THC and 50 ng/ml for THC-COOH.

Martin died from a gunshot wounded to chest fired from "intermediate range," according to the medical examiner's report, which was one of several documents on the case released Thursday by the office of special prosecutor Angela Corey.

The autopsy report lists the manner of death as a homicide.

Zimmerman, 28, is charged with second-degree murder for killing Martin in the Sanford neighborhood where the African-American teen was staying.

A police report, released earlier, had noted that Zimmerman claimed he'd been "assaulted (by Martin) and his head was struck on the pavement."

According a report from the Sanford Fire Department, released Thursday, Zimmerman had "abrasions to his forehead," "bleeding/tenderness to his nose," and a "small laceration to the back of his head" when he was treated at the scene.

Prosecutors have said Zimmerman, who is a white Hispanic, killed the unarmed teenager unjustly after profiling him. Zimmerman, who has pleaded not guilty, has said that he shot Martin in self-defense.

The start of the trial hasn't been set.

The case put a spotlight on race relations, spurring protests nationwide and drawing prominent civil rights leaders to central Florida denouncing the actions of Sanford police and calling for Zimmerman's arrest. Special prosecutor Angela Corey announced he'd been charged on April 11, weeks after Sanford police initially declined to do so.

It also raised questions about gun laws, as well as the merits of the "Stand Your Ground" law in Florida, and similar laws in other states that allow people to use deadly force anywhere they feel a reasonable threat of serious injury or death.