For years, residents in Middleborough have sought to connect dozens of cases of a devastating neurological disease in the vicinity of the town’s center to pollution from a trio of nearby toxic waste sites.
At a public meeting Thursday — 13 years after a federally funded study was first launched to investigate the suspected connection — state health officials will release findings showing no evidence of a geographic cluster of amyotrophic lateral sclerosis, or ALS, in Middleborough, no elevated incidencesof the disease, and no apparent relationship to industrial contamination.
Epidemiologists from the Massachusetts Department of Public Health will reveal the results of the analysis at 7 p.m. in the John T. Nichols Middle School auditorium, off Wood Street.
Concerned residents like Wally Glendye, a former member of the town’s Citizens Environmental Health Impact Committee, which is hosting the event, are already questioning the report’s findings, contradicting the state’s numbers that say 17 cases of ALS were identified from 1938 to 1988. Glendye, who lives downstream from the industrial sites located along the Nemasket River, said he and other citizens had counted 34 ALS cases when the study began, and three additional cases since then.
“We also have a cluster of multiple sclerosis, and 14 to 15 women with breast cancer,’’ said Glendye, a Plymouth Street resident. “We are all on well water. I definitely doubt the study.”
Anne Roach, a spokeswoman for the Department of Public Health, said health officials would offer further comment on the study at the meeting.
Some Middleborough residents, including Perry Little, chairman of the Citizens Environmental Health Impact Committee, were taking more of a wait-and-see approach.
“I may have questions about the report, and whether it went back far enough with some of the involved sites,’’ said Little, who acknowledged he was still going through the data, first revealed this month during a meeting at Weymouth Town Hall.
ALS is a neurodegenerative disease that destroys a person’s ability to control movement. Patients lose the ability to move and speak, but their minds remain clear. Also known as Lou Gehrig’s disease, it is nearly always fatal, usually within a few years of diagnosis, and its cause remains unknown.
The state’s study, paid for in 2002 by the Agency for Toxic Substances and Disease Registry, was delayed due to funding issues. It investigated cases of ALS and multiple sclerosis in 30 communities south of Boston from 1998 to 2003.
An elevated prevalence of the latter disease was reported in Abington, Rockland, and Weymouth — communities that surround the former South Weymouth Naval Air Station — but the report said patients in those towns did not necessarily live close to the facility, the suspected source of chemical and metal contamination.
Middleborough officials first raised concerns about ALS in 1987, fearing possible exposure to contaminants in the Cambridge Street area, according to the study.
The area included Rockland Industries, a former chemical manufacturing and packaging facility from the mid-1960s; the Middleborough Plating Co., which operated from the mid-1960s to 1991; and the Gerson Co. property, used for sewage disposal beginning in the early 1900s.
In the Gerson case, state officials said, it was not learned until the mid-1960s that industrial waste from Middleborough Plating was also discharged into the sewage system.
The sites are either already capped or undergoing remediation.
Middleborough originally identified 11 possible cases of ALS, according to the report, which said the study revealed a total of 17 ALS cases from 1938 to 1988.
Based upon death certificate data, researchers estimated the town’s ALS death rate from 1969 to 1985 to be 2.5 deaths per 100,000 people, compared with the statewide rate of 1.26 deaths per 100,000 people.
The study found 43 people with ALS in Southeastern Massachusetts , or 2.4 verified cases per 100,000 — a ratio that is statistically lower than the national rate of 4 to 6 cases per 100,000 people, officials said.
While Middleborough had no diagnosed ALS cases during the study years, officials said some medical records were incomplete and other cases reported by patient advocacy groups could not be reviewed and verified.
It is also “reasonable” to assume, they said, “that air emissions from operations at Middleborough Plating could have resulted in exposure to nearby and downwind residents.”
But to what degree people could have been exposed “to stack or fugitive air emissions” due to the lack of historical emissions data is tough to estimate, they added.
The diseases will be monitored in the four towns, the study said.
Although some residents question the study’s results, Lynn Aaronson, executive director of the ALS Association Massachusetts Chapter, said the reality is that the state’s study revealed no significant numbers.
Disease pockets could become apparent when findings are released from the state’s ALS registry, which has been in place since 2008, she said, “but they have to be grounded in fact. It could be strictly coincidence.”
Updates on the statewide registry and on work underway to evaluate potential past and current health risks associated with the industrial sites are also on the meeting’s agenda.
Going forward, officials also plan to evaluate cancer patterns near the properties, and for Middleborough as a whole, according to a letter to the committee by Robert Knorr, the state director of the Environmental Epidemiology Program Bureau.
Knorr could not be reached for comment.Michele Morgan Bolton can be reached at michelebolton@ live.com.