The rate of deaths due to opioid overdoses is slowing in Massachusetts, but still nearly 1,500 people died of an overdose in Massachusetts through the first nine months of the year, the state announced Monday.

The 1,460 confirmed or suspected opioid-related overdose deaths in Massachusetts between January and September represent a decrease of about 6 percent from the first three quarters of 2018, the equivalent of 99 fewer people dying of an overdose, the Department of Public Health said. DPH has confirmed 1,091 of the deaths were caused by an overdose of heroin, fentanyl, prescription painkillers or other opioids and estimated that another 332 to 407 deaths will eventually be confirmed as opioid overdoses.

For the second time in two quarterly opioid data releases, DPH officials said that the prevalence of the powerful synthetic opioid fentanyl has risen to "an all-time high" and is now present in almost every overdose death that's screened for drugs.

"Today's report affirms that our multi-pronged approach to the opioid epidemic is making a difference," Gov. Charlie Baker said in a statement. "Although we've made progress, we must continue to focus our law enforcement efforts on getting fentanyl off of our streets and out of our neighborhoods."

Of the 903 opioid-related overdose deaths in 2019 for which a toxicology screen was present, 838 of them -- or 93 percent -- tested positive for the presence of fentanyl, which is deadly in small doses. Last year, the fentanyl was found in 89 percent of opioid overdose deaths and was present in just 18 percent of opioid overdose deaths in the third quarter of 2014, DPH said.

Over the last five years, while fentanyl has been on the rise in Massachusetts, the rate of heroin or likely heroin found present in opioid-related overdoses has declined steadily, DPH said, and it was found in 24 percent of overdose deaths that had a toxicology screen in the second quarter of this year.

Men aged 25 through 34 continued to make up the greatest demographic share (24 percent) of all opioid-related incidents treated by emergency medical services in the first half of 2019, DPH said. Men account for 74 percent of all fatal opioid-related overdoses in Massachusetts.

"Behind these quarterly data are real people and families in communities across the state whose lives are impacted by addiction," Lt. Gov. Karyn Polito said. "We remain invested in proven strategies across the spectrum of prevention, intervention, treatment, and recovery to help individuals struggling with addiction and support local community efforts."

The Baker administration has focused on the opioid epidemic since the governor took office in 2015, but has seen overdose deaths climb about 50 percent from the 1,351 deaths in 2014 to the 2,033 in 2018 despite having "doubled spending to address the opioid crisis" and having "increased capacity by more than 1,200 treatment beds." In terms of deaths, the epidemic peaked in 2016 when 2,095 people died of opioid-related overdoses.

The current state budget directs $246 million -- or roughly 0.6 percent of the total state appropriation -- towards addressing substance misuse prevention and treatment.

Despite the surge in the presence of fentanyl, public health officials have touted declines in the number of overdose deaths. Between 2016 and 2018, total overdose deaths dropped by an estimated 3 percent, and the rate of deaths per 100,000 people fell by 4 percent in that same time period, DPH has said.

"The release of this latest data indicates that our public health-centered approach to the opioid epidemic is working," Public Health Commissioner Monica Bharel said. "As we move forward, we will build on this success by continuing to focus on the widespread availability of naloxone, behavioral and medication treatments, and sustained recovery services."